[House Hearing, 112 Congress] [From the U.S. Government Printing Office] [H.A.S.C. No. 112-154] F-22 PILOT PHYSIOLOGICAL ISSUES __________ HEARING BEFORE THE SUBCOMMITTEE ON TACTICAL AIR AND LAND FORCES OF THE COMMITTEE ON ARMED SERVICES HOUSE OF REPRESENTATIVES ONE HUNDRED TWELFTH CONGRESS SECOND SESSION __________ HEARING HELD SEPTEMBER 13, 2012 [GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT] ---------- U.S. GOVERNMENT PRINTING OFFICE 76-215 PDF WASHINGTON : 2012 For sale by the Superintendent of Documents, U.S. Government Printing Office Internet: bookstore.gpo.gov Phone: toll free (866) 512-1800; DC area (202) 512-1800 Fax: (202) 512-2104 Mail: Stop IDCC, Washington, DC 20402-0001 SUBCOMMITTEE ON TACTICAL AIR AND LAND FORCES ROSCOE G. BARTLETT, Maryland, Chairman FRANK A. LoBIONDO, New Jersey SILVESTRE REYES, Texas JOHN C. FLEMING, M.D., Louisiana MIKE McINTYRE, North Carolina TOM ROONEY, Florida JIM COOPER, Tennessee TODD RUSSELL PLATTS, Pennsylvania NIKI TSONGAS, Massachusetts VICKY HARTZLER, Missouri LARRY KISSELL, North Carolina JON RUNYAN, New Jersey MARTIN HEINRICH, New Mexico MARTHA ROBY, Alabama BILL OWENS, New York WALTER B. JONES, North Carolina JOHN R. GARAMENDI, California W. TODD AKIN, Missouri MARK S. CRITZ, Pennsylvania JOE WILSON, South Carolina KATHLEEN C. HOCHUL, New York MICHAEL TURNER, Ohio JACKIE SPEIER, California BILL SHUSTER, Pennsylvania DOUG LAMBORN, Colorado John Sullivan, Professional Staff Member Doug Bush, Professional Staff Member Scott Bousum, Staff Assistant C O N T E N T S ---------- CHRONOLOGICAL LIST OF HEARINGS 2012 Page Hearing: Thursday, September 13, 2012, F-22 Pilot Physiological Issues.... 1 Appendix: Thursday, September 13, 2012..................................... 35 ---------- THURSDAY, SEPTEMBER 13, 2012 F-22 PILOT PHYSIOLOGICAL ISSUES STATEMENTS PRESENTED BY MEMBERS OF CONGRESS Bartlett, Hon. Roscoe G., a Representative from Maryland, Chairman, Subcommittee on Tactical Air and Land Forces......... 1 Reyes, Hon. Silvestre, a Representative from Texas, Ranking Member, Subcommittee on Tactical Air and Land Forces........... 3 WITNESSES Cragg, Clinton H., Principal Engineer, National Aeronautics and Space Administration (NASA) Engineering and Safety Center...... 11 Lyon, Maj Gen Charles W., USAF, Director of Operations, Headquarters Air Combat Command, U.S. Air Force................ 7 Martin, Gen Gregory S., USAF (Ret.), Aircraft Oxygen Generation Study Chair, USAF Scientific Advisory Board.................... 4 APPENDIX Prepared Statements: Bartlett, Hon. Roscoe G...................................... 39 Cragg, Clinton H............................................. 99 Lyon, Maj Gen Charles W...................................... 60 Martin, Gen Gregory S........................................ 46 Reyes, Hon. Silvestre........................................ 42 Documents Submitted for the Record: [There were no Documents submitted.] Witness Responses to Questions Asked During the Hearing: Ms. Speier................................................... 105 Questions Submitted by Members Post Hearing: Mr. Bartlett................................................. 109 Mr. Loebsack................................................. 116 Mr. Runyan................................................... 113 Ms. Speier................................................... 115 F-22 PILOT PHYSIOLOGICAL ISSUES ---------- House of Representatives, Committee on Armed Services, Subcommittee on Tactical Air and Land Forces, Washington, DC, Thursday, September 13, 2012. The subcommittee met, pursuant to call, at 10:02 a.m., in room 2118, Rayburn House Office Building, Hon. Roscoe G. Bartlett (chairman of the subcommittee) presiding. OPENING STATEMENT OF HON. ROSCOE G. BARTLETT, A REPRESENTATIVE FROM MARYLAND, CHAIRMAN, SUBCOMMITTEE ON TACTICAL AIR AND LAND FORCES Mr. Bartlett. The hearing will come to order. The subcommittee meets today to receive testimony on F-22 pilot physiological issues which have resulted in reported hypoxia- like events by F-22 pilots over a period of several years. The committee's concerns include the impacts of these physiological issues to the pilots and operational capability of these valuable aircraft, as well as the ultimate cost and time required to implement the recommendations that have been made to modify the F-22 life support system. The committee also remains concerned that after all of the study of the issue, we need to understand what the level of confidence is that the cause or causes of the F-22 physiological issues are fully known. From 2003 to April 2008, there were 6 F-22 physiological issues, but between April 2008 and January 2011, that number had doubled to 12. As a result of this, the Air Force Commander of Air Combat Command restricted the F-22's maximum flight attitude to 25,000 feet and directed a safety investigation board to review the F-22's oxygen system. In May of 2011, the Secretary of the Air Force directed the Scientific Advisory Board to gather information and make recommendations to address concerns relative to the F-22 life support system. From May to September of last year, the F-22 fleet stood down as a result of an upward trend in reports of physiological incidents. The Scientific Advisory Board [SAB] completed its work in January of this year but did not determine a cause for the F-22 pilot physiological problems. However, the board did make findings and recommendations and concluded that either the supply or the quality of the oxygen is contributing to the F-22 pilots' hypoxia-like symptoms. Air Combat Command established a Life Support System Task Force, which continued to examine both the issues of supply and quality of oxygen in the F-22. On April 23, 2012, the National Aeronautics and Space Administration, NASA, accepted a request from the Air Combat Command to form an independent investigative team to review Air Combat Command's investigative process, ongoing root cause analysis, and the F-22 life support system as a whole to determine potential vulnerabilities to the pilot. On July 24th, the Department of Defense announced that Air Combat Command had determined that the root cause of the F-22 pilot physiological issues is the supply of oxygen delivered to the pilots, not the quality of oxygen delivered to the pilots. To correct the supply issue and reduce the incidence of related hypoxia-related events, the Air Force has made two changes to the aircraft's cockpit life support system. First, the Air Force has increased the volume of air flowing to pilots by removing a filter that was installed as a part of the investigation to determine whether there were any contaminants present in the oxygen system. Second, the Air Force will replace a valve in the upper pressure garment worn by pilots during high-altitude missions. The upper pressure garment is designed to provide counterpressure to assist pilots' breathing and to help counteract the effects of G-forces. The garment valve was causing the vest to inflate and remain partially inflated under conditions where it was not designed to do so, thereby causing breathing problems for some pilots. Oxygen contamination was ruled out as potential cause. The Air Force is also exploring ways to improve the oxygen delivery hose and its physical connections. In the interim, the F-22 is under a temporary altitude limit of 44,000 feet. Since the F-22 returned to flying status in September of 2011, there have been 11 hypoxia incidents where the incidents were initially reported as cause unknown. The Air Force continues to investigate these incidents, and as of late July, less than half of those were still unresolved. There have been no cause unknown hypoxia incidents in the F-22s since March of 2012. From fiscal year 2002 to May 2011, the Air Force reports an incidence rate of 13 hypoxia events per 100,000 hours compared to 7.5 in the F-16, and 1.8 in the F-15E, and 6.6 in the F-18E, F and G, over roughly the same period. I know from personal experience as a scientist working with these issues before I came to Congress that the Air Force faced a difficult problem in determining the root cause of these 22 pilot hypoxia-like events because symptoms of hypoxia and hypocapnia, also know as hyperventilation, are very difficult to distinguish. Indeed, pilot concerns about hypoxia will frequently result in hyperventilation, imperceptible to the pilot, which will produce hypoxia-like symptoms, eliciting even more hyperventilation, a vicious cycle. A significant amount of effort has gone into solving the F- 22 physiological issues, but much more needs to be done. Recommendations of the Air Force Scientific Advisory Board's Oxygen Generation Study Group needs to be implemented. The Air Force Air Combat Command Life Support Systems Task Force needs to complete its report and provide its final recommendations. Additionally, NASA's Engineering and Safety Center needs to complete final report and provide its recommendations. The committee expects the Air Force to keep Congress up to date on the status of all of these reports and recommendations. To address the F-22 physiological issues, we have asked the three key leaders involved in this project to testify today: Retired Air Force General Gregory S. Martin, Chairman of the Air Force Scientific Advisory Board Quick Look Study on Aircraft Oxygen Generation. General Martin, welcome back. Major General Charles Lyon, Director of Operations for the Air Combat Command. General Lyon leads the F-22 Life Support System Task Force. Finally, Mr. Clinton H. Cragg, principal engineer at NASA's Engineering and Safety Center. Mr. Cragg leads NASA's independent investigative team, which has reviewed Air Combat Command's F-22 processes and analyses. Gentlemen, we thank you all for your service to our country. Before we begin, let me call on the ranking member of the subcommittee, Mr. Reyes, for his opening remarks. [The prepared statement of Mr. Bartlett can be found in the Appendix on page 39.] STATEMENT OF HON. SILVESTRE REYES, A REPRESENTATIVE FROM TEXAS, RANKING MEMBER, SUBCOMMITTEE ON TACTICAL AIR AND LAND FORCES Mr. Reyes. Thank you, Mr. Chairman. And let me add my welcome to you this morning, gentlemen. From a personal perspective, I want to thank the Chairman because as a scientist, he was able to explain some of these very difficult technical issues with the problem that we have been wrestling with now with the oxygen system of the F-22. So, Mr. Chairman, I wanted to thank you publicly for--on this committee, for having the expertise to be able to do that, and thank you for your leadership as well. Today's hearing on the F-22 will cover many technical issues, as I mentioned, that have been associated with the F- 22's pilot life support system. On balance, I am pleased with the level of effort that the Air Force has put into this investigation. It is clear that the current senior Air Force officials have taken this issue very seriously and have put in place the necessary resources and organizations needed to identify the problem and eventually to get to a place where we fix this problem. The scale of the testing and the evaluation effort for a tactical fighter aircraft is, from my view point, unprecedented. Rather than staying in a defensive posture, the Air Force reached out to other agencies and other military services for additional expertise and for advice. Based on the extensive work done by the Air Force and other DOD [Department of Defense] agencies, I am cautiously optimistic that the Air Force has indeed identified the primary causes of the hypoxia problems with the F-22, has identified fixes that, from a layman's perspective, seemed to make sense. The next step is ensuring that the fixes identified are funded and installed as rapidly as possible. The United States clearly needs the F-22 to deter our enemies and to provide critical capabilities if we go to war. Despite Congress passing a long-term continuing resolution for defense spending, I personally want to ensure that efforts to fix the F-22 problems can continue at full speed. So understanding the F-22's problems and how to fix them is one aspect of today's hearing and a very important one. However, the larger issue that I hope today's hearing will touch on is how this situation occurred in the first place, and how we avoid similar mistakes going forward. As far as the cause of the F-22's problems, my overall impression from the testimony that we have received and other information provided to our committee is that the main problems with the F-22 were human failures of judgment and not technical failures. One issue that appears to have gone wrong was a basic design of the aircraft's life support system. The F-22 is the most capable and, I should add, expensive fighter aircraft ever developed. The F-22 also operates at higher altitudes and in a more demanding performance envelope, perhaps more than any other fighter in the history of this country. Given these two factors, a cost per plane of more than $140 million and a unique flight environment, it is very surprising that it was designed, again from a layman's perspective, with--designed without a sophisticated backup oxygen system or even enough instrumentation to let the pilot know that he wasn't getting oxygen in time to actually do something about it. So one question that confronts the subcommittee is, how did that happen? Why did the Air Force design and build such a sophisticated aircraft with such a relatively unsophisticated pilot oxygen support system? In addition, why wasn't this issue identified during testing of the aircraft? That is normally when serious design issues are identified for future fixes. But that doesn't seem to have been the case with the F-22. We are going to get a lot of information today, but in particular, I look forward to hearing from the Air Force witnesses and, again, welcome, how they think we got to this point and how we can avoid similar problems with other aircraft in the future. And with that, Mr. Chairman, I want to yield back to you. [The prepared statement of Mr. Reyes can be found in the Appendix on page 42.] Mr. Bartlett. Thank you very much. Without objection, all witnesses' prepared statements will be included in the hearing record. General Martin, please proceed with your opening remarks. You will be followed by General Lyon and Mr. Cragg. STATEMENT OF GEN GREGORY S. MARTIN, USAF (RET.), AIRCRAFT OXYGEN GENERATION STUDY CHAIR, USAF SCIENTIFIC ADVISORY BOARD General Martin. Thank you, Mr. Chairman. Chairman Bartlett and Ranking Member Reyes and other distinguished members of this committee, I am honored to be here today representing the members of the Air Force Scientific Advisory Board Study Panel on Aircraft Oxygen Generation Systems. During my remarks and during my responses to any questions that I receive, I will try to answer the questions as I believe the members of the study panel would answer them, as opposed to my own personal views. The onboard oxygen generation system [OBOGS] on the F-22 is very similar to other onboard oxygen generation systems that we have on many fighter aircraft. And they were designed to reduce the servicing, logistic support and safety--and increased safety considerations. The F-22 aircraft is equipped with such a system to provide breathing air to the pilot, and this system usually, in the F-22 as well as the other aircraft, will take bleed air off of the engine, concentrate it into a higher level of oxygen and then match that amount of oxygen to the breathing air, based on the cabin pressure and altitude. Beginning in 2008, as the chairman pointed out, the F-22 began to experience a significantly higher rate of hypoxia-like incidents with unknown causes, as reported by the pilots. At that point, the Air Force initiated what I will refer to as a four-tier approach to finding the root cause for these unexplained physiological incidents. The first tier was a collaborative effort between the F-22 system program office, the prime contractor and its key subcontractors responsible for the components of the F-22 life support system, and the normal Air Force safety investigation structure. So that collaborative effort started a process we have come to know as the Root Cause and Corrective Action [RCCA] analysis process that has continued for the last 4\1/2\ years. The second tier was initiated after preliminary results of the tragic fatal F-22 mishap that occurred in November of 2010. When that mishap was out-briefed to the senior leadership in January of 2011, the Air Combat Command established a Class E safety investigation mishap board. That board was chaired by an Air Force Major General, and it was chartered to review all F- 22 reported hypoxia-like incidents. So, in conjunction with the RCCA team, or the Root Cause and Corrective Action Analysis Team, this safety investigation team developed and implemented a multitude of tests and challenges to each of the F-22s life support system components. At that time, the F-22 flight operations were limited to 25,000 feet and the pilots were directed to fly in the maximum oxygen production mode, known as max. These directions were provided to minimize the opportunity for any of the crews to be exposed to an environment that could cause hypoxia-like symptoms, so lower altitude and use of 100 percent oxygen direction was given to prevent or preclude future hypoxia-like incident. Nonetheless, there was an increase in the number of hypoxia-like events. And after two troubling incidents in May of 2011, the Air Force grounded the fleet of F-22 aircraft. At that point, the Safety Investigation Board, which had been unable to determine a failure mode that might lead to the hypoxia-like events, recommended that the Air Force modify one of its test aircraft with a specialized array of sensors and then execute a carefully developed series of flight test profiles to determine if the root cause could be assessed in the dynamic flight environment as opposed to the ground testing that had been done to that point. Further, as a part of their investigation, the Safety Board determined there were decisions made during the engineering, manufacturing and development phase of the F-22's development that should be reviewed from a broader perspective, and they recommended a broad area review of the F-22 program be conducted. So, in June of 2011, the Secretary of the Air Force and the Chief of Staff of the Air Force tasked the United States Air Force Scientific Advisory Board to perform a quick- look study on aircraft oxygen generation systems and to cover three areas: First, continue the ongoing efforts to determine the root cause, to include gathering data during dynamic in- flight testing, full reviews of both the life support equipment and the aircraft's potential for passing contaminants into the cockpit and/or the breathing air, and finally, to better understand the similarities and differences between the F-22 oxygen generation system and other military aircraft; second, to better understand the conditions that would create hypoxia- like symptoms at altitudes not normally associated with hypoxia, along with an evaluation of the guidance associated with breathing air standards and the human response to operating in the F-22's extraordinary envelope with less than 90 percent supplied oxygen; third, to review the policies, processes and procedural changes that occurred during the F- 22's development and fielding phase to evaluate the implications with respect to design limitations, risk analysis, program execution and the acquisition workforce. The study began in June of 2011, with interim status reports provided to Secretary and the Chief until the final briefing was approved by the entire Scientific Advisory Board and delivered to the Secretary and the Chief on the 24th of January 2012. This activity actually represents the third tier of effort in determining root causes. It is important to note that SAB study panel recognized from some initial statistical analysis that it was quite likely that in the initial flight test profiles conducted during the summer of 2011, that we may not determine the root causes in that limited sample of flight. With that in mind, it became clear that it would need to develop or help the Air Force develop an appropriate risk-mitigation procedure to allow the F-22 fleet to return to flight operations in a safe mode that would provide the Nation with its critical combat capabilities while at the same time offering Air Force--the Air Force the ability to collect and analyze the voluminous amount of data that would be collected during these flights and to continue their investigation in determining root causes for the unexplained physiological incidents. As a result, the SAB study manual was able to develop a protocol of aircraft inspections, crew training, crew protection devices and procedures, along with a specific series of incident response protocols to assist the Air Force in zeroing in on the root causes or root causes. With that in mind, the Air Force chose to resume F-22 flight operations in September 2011. Between that time and the AFSAB, or the Scientific Advisory Board's, out-brief to the Secretary and to the Chief in January 2012, the AFSAB continued to assess and evaluate data from approximately 7,500 sorties. As a result of analyzing the emerging stream of data, the study panel completed its study effort and made recommendations to the Air Force leadership in third areas that would, one, in the near term, allow the Air Force to complete its root-cause analysis and safely return the F-22 to its full operational flight envelope; two, over the next several years, modify the aircraft and develop specific F- 22 tools to improve the margin of safety related to the F-22's entire life support system design and performance and develop procedures related to the human system's integration process that the Air Force uses to further explore the interaction between the human and the F-22 in all of its environment. They also directed that the Air Force take the lead in establishing comprehensive aviation breathing air standards applicable to the environments in which all of its aircraft would operate. The key to implementing the AFSAB study panel recommendations was determined to be the establishment of a task force to continue the data-gathering and analysis process initiated by the AFSAB study panel, while at the same time developing the implementation plans to finalize and close out the remaining recommendations. Standing up this task force, which has been directed by Major General Lyon, next to speak, represents the fourth tier of the Air Force's overall effort to find the root causes to the unexplained physiological incidents. As a final note, I would mention that the study panel did recommend a quarterly follow-up be established to review the process on completing the recommendations and that the AFSAB would be available for support, if required. To date, the task force has completed two quarterly follow-ups and presented their reports to the AFSAB. And their progress has been impressive. In summary, I believe this four-tier approach, coupled with the Air Force's request from NASA for an independent assessment of their process and their recommendations represents that the Air Force is dedicated to being thorough, credible and transparent in its approach to solving this difficult issue. This completes my initial statement, and I look forward to your questions. [The prepared statement of General Martin can be found in the Appendix on page 46.] Mr. Bartlett. Thank you very much. General Lyon. STATEMENT OF MAJ GEN CHARLES W. LYON, USAF, DIRECTOR OF OPERATIONS, HEADQUARTERS AIR COMBAT COMMAND, U.S. AIR FORCE General Lyon. Chairman Bartlett, Ranking Member Reyes, distinguished members of the committee, thank you for the opportunity today to discuss an issue of great importance to the United States Air Force, the F-22 pilot physiological issue. Mr. Chairman, I would like to thank you for the steadfast leadership of this committee and to your members for their unwavering support and commitment to the men and women of the United States Air Force and the entire Department of Defense. This committee has helped ensure our men and women are equipped and resourced to meet the responsibilities in support of national security objectives at home and abroad over the years. The F-22 Raptor contributes significantly to our Nation's interest vital interest by providing air dominance when and where ordered to protect and enable the joint military force. Today, we have F-22s forward deployed to support the objectives of geographic combatant commanders in the Central Command, and Pacific Command areas of operations. This forward presence reassures our allies, enhances joint and coalition interoperability, and demonstrates our resolve for lasting global relationships. We also have continental United States based F-22s contributing to homeland defense, while the remainder of the fleet conducts combat-mission-ready training, formal replacement unit training and operational test and evaluation. The F-22's attributes, stealth, supercruise, maneuverability, and integrated avionics, ensure our ability to project power anywhere on the globe, including anti-access and area denial environments. Simply stated, the F-22 fleet, combined with complementary capabilities from our joint partners, allows us to kick down the door and enable joint operations in the most demanding environments that exist now and in the foreseeable future. The F-22's multi-mission capabilities allow us to seize the initiative, achieve air superiority, attack those who challenge us in the skies, and to defeat those who would challenge us from the ground. The F-22 contributes significantly to protect the joint force from attack, while enabling the joint force to conduct offensive operations. The capabilities of the F-22 weapon system are compelling, but without the contributions of the men and women who fly, fix and support F-22 operations, the Raptor would never leave the ground. Flying high-performance fighter aircraft is not risk- free. But the risk is measured against mission priorities and probabilities of success. Just as other airmen and members of the joint force accept risk in the conduct of their daily military duties, we accept risk in operating the F-22. To set the context for this issue's history, as the chairman said, F-22 fleet experienced six physiological incidents in our initial phases over a 5-year period. The number of incidents more than doubled in the next 3 years. The increased number of incidents in 2008 to 2011, the ambiguities and uncertainties at the time surrounding Captain Haney's November 2010 tragic and fatal mishap, and the unexplained nature of these incidents gave the Air Force grave concern, which prompted the fleetwide standdown in May 2011. Although the total percentage of physiological incidents at the time of the standdown represented less than 0.1 percent of all sorties flown to date, that wasn't good enough, and it did not meet our service established safety standards. The risk to the safety of our airmen posed by uncertainty and ambiguity exceeded our threshold. During the standdown, the Air Force expanded analytic capabilities beyond the use of normal governmental resources to include additional expertise from the public and private sectors. After months of research, testing, and analysis, General Martin's study group provided a set of recommendations to the Air Force September of last year. This put us on the path to safely return the F-22 fleet to flight operations with an acceptable level of risk. The recommendations were reviewed and implemented with the F-22 fleet returned to flying just under a year ago, September 21st, 2011. Between September 2011 and today, the Air Force has continuously analyzed the previously unexplained physiological incidents, implemented and adjusted risk-mitigation measures, and incorporated corrective actions to enhance the safety of the F-22 Raptor fleet. General Martin's study group completed their investigative actions in January of this year. Following General Martin's presentation to Air Force leaders, the Secretary of the Air Force formed the F-22 Life Support Systems Task Force, led by me, to continue this analytic effort and implement corrective actions. Our integrated, collaborative, multi-service, cross- functional, government/industry team approach permitted an increased breadth of experience, enhanced scope of knowledge and provided additional and partial expert analysis, which was critical in the determination of root causes. The task force has considered the inputs, findings and recommendations of the previously convened F-22 Safety Investigation Boards, Scientific Advisory Board and Lockheed Martin's Root Cause and Corrective Analysis Team. We have integrated their findings, continued the investigative process, and drawn conclusions that could not have been reached without the benefit of this collaborative approach. The previously unexplained F-22 physiological incidents were the result of multifactorial combinations. The trend over time has eliminated system-specific factors related to oxygen delivery system components. During our analysis timeframe, Major Dr. Marsha Mitchum, seated behind me, an F-22 flight surgeon at Joint Base Langley-Eustis, conducted independent research with Duke University and the Naval Surface Warfare Center in Panama City, Florida. Through her efforts and coordination, the naval experimental dive unit became involved to offer an assessment on life support issues and breathing devices. This research opened a door for new analysis that had not been addressed to this point in our Air Force investigative process. This would turn out to be a decisive moment for F-22 investigative efforts. We convened an F-22 Restrictive Breathing Working Group at Langley in April of this year. The task force facilitated this session, lead by Lieutenant Colonel Jeff Hawkins, seated behind me, from the First Fighter Wing, an F-22 pilot. This group consisted of F-22 pilots, engineers, medical and safety professionals from the Air Force, Air Force Combat Command, Air Force Materiel Command; from the Navy, both the Experimental Dive Unit, their Surface Warfare Center; Naval Air Systems Command [NAVAIR] from NASA, Wyle Labs, Lockheed Martin and Boeing, an impressive group of professionals gathered together to work this issue. Additionally, the task force sought NASA's assistance to review our post-incident protocols and, if warranted, recommend enhanced procedures with a greater emphasis on integrated life support systems and cabin pressurization systems analysis. Concurrently, we requested that NASA form an independent team to review our investigative process in the entire F-22 life support system to determine potential vulnerabilities to the pilot. The NASA Engineering and Safety Center [NESC] provided that team, lead by Mr. Clint Cragg, sitting here to my left here today. I would like to thank Mr. Cragg and his team for their unique insight and contributions to our efforts. Two weeks ago, Mr. Cragg presented his findings and recommendations to me for incorporation in our analysis. While corroborating much of what we had researched, the team also presented additional measures for our consideration. The task force is confident that data derived from General Martin's group hypothesis one, oxygen quantity, describes the major contributors to the previously unexplained physiological incidents reported by F-22 pilots over the past few years. The task force is confident that the hypothesis two, oxygen quality, is not the root cause of previously unexplained physiological symptoms reported by F-22 pilots and ground crew. Systemic factors in the life support system, such as the Combat Edge upper pressure garment and the C2A1 filter functionalities, have been identified, removed and corrective action is underway. We have reduced the potential negative affects created by high oxygen concentration levels produced by the OBOGS through cockpit selectable oxygen sittings. Human factors at two F-22 operating locations were contributory. We have communicated findings and corrective actions to the community. This communication has reduced the ambiguity and uncertainty, while significantly increasing pilot and ground crew confidence in the F-22's life support systems. Mr. Chairman, we have more work ahead as we transition to normal F-22 flight operations. The path to resuming normal flight operations hinges on the successful development, testing, and fielding of the modified Combat Edge upper pressure garment valve. This modification will successfully integrate the key components of the F-22 life support system to ensure adequate oxygen flows to the pilot, while providing protection in the high-altitude and high-G environments where the F-22 flies. We expect this modification to be fielded by the end of 2012. I have had the opportunity to present task force interim findings, recommendations, and corrective actions to Department of Defense and Department of the Air Force senior leaders throughout this investigation. Department leaders have expressed keen interest to fixing the F-22's life support system vulnerabilities, to maximize the safety of the men and women who operate and maintain this aircraft, and have provided us the required resources and support to bring this issue to conclusion. The fielding of the automatic backup oxygen system will provide additional protection to F-22 pilots while flying at high altitude and under the most demanding oxygen delivery system scenarios that can be envisioned for the F-22 lifecycle. We expect the first operation aircraft will be modified in January 2013, the first operational squadron complete by the spring of 2013, and the entire fleet complete by mid 2014. We are certain the F-22 cockpit and surrounding workspace is a safe, effective place to operate, but the Air Force is an organization that is built on the foundation of innovation, self-improvement, and ingenuity. Continuous process improvements will ensure the safety of the F-22 workforce now and in the future. To date, since we resumed flight operations last September, we have flown nearly 20,000 sorties, totalling over 25,000 hours, while encountering 11 previously unexplained in-flight incidents and 6 ground-related physiological incidents. None of these incidents have resulted in the loss of life, loss of aircraft control, nor lingering effects for our pilots and ground crews. Importantly, we have not encountered an unexplainable incident since March 8 of this year. Since that time, we have flown more than 10,000 sorties, totalling over 13,000 hours, without incident. The trend is on a positive vector not seen in years. There will be physiological incidents in the future. The harsh high-altitude, high-G environment is extremely demanding, and our pilots are aware of those demands. We encounter physiological incidents in all high-performance aircraft--it is a fact of life--due to the demands placed on our air crew. The measures taken by the Air Force, in my opinion, will reduce the incident rate significantly and over time bring the F-22 incident rates in line with comparable high-performance aircraft. The Air Force is committed to implementing these changes to return the F-22 to normal operations, thus significantly contributing to our Nation's vital interests by providing air dominance when and where ordered to protect and enable the joint U.S. military force. The Air Force will continue to leverage lessons learned throughout this investigative process, and will invest in characterizing and understanding the high-performance aircraft environment to optimize pilot performance, not only in the F-22 but in all current and future weapon systems. Mr. Chairman, I look forward to answering your questions. [The prepared statement of General Lyon can be found in the Appendix on page 60.] Mr. Bartlett. Thank you. Mr. Cragg. STATEMENT OF CLINTON H. CRAGG, PRINCIPAL ENGINEER, NATIONAL AERONAUTICS AND SPACE ADMINISTRATION (NASA) ENGINEERING AND SAFETY CENTER Mr. Cragg. Chairman Bartlett, Ranking Member Reyes, members of the subcommittee, thank you for this opportunity to discuss the NASA Engineering and Safety Center's independent assessment of the F-22 life support system. I am honored to be serving as the lead of this NESC team. The NESC performs independent testing, analysis and assessments to help address some of NASA's tougher challenges. We can draw upon technical experts from all 10 NASA centers, industry academia and other government agencies. This allows us to bring the country's best experts to bear on problems and challenges of NASA programs. In April 2012, Major General Lyon requested NASA's assistance in their efforts to determine the cause of the hypoxia-like symptoms experienced by some F-22 pilots. NASA was requested to review current post-incident protocols and recommend enhanced procedures and also review the current investigative process, ongoing root cause analysis and the F-22 life support system as a whole. The NESC assembled a team that included two NASA flight surgeons, two NASA human factor experts, an EPA [Environmental Protection Agency] forensic chemist, an industry oxygen generator system expert and several specialized NASA life support systems engineers. In the course of this investigation, the team reviewed data from multiple sources, visited manufacturing sites and F-22 bases and held numerous discussions with knowledgeable personnel. The NESC team's findings and recommendations are based on this data and not on an exhaustive review of all F-22 documentation. The NESC team concurs with the Air Force that the F-22 incidents can be attributed to several factors: One, the high concentrations of oxygen at lower altitudes; two, the inevitable acceleration which compounds the effects of high oxygen; three, restricted breathing due to the inappropriate inflation of the upper pressure garment; and four, contribution of uncharacterized F-22 life support system vulnerabilities, such as pressure drops [across] components in the cockpit. The NESC team found a number of issues with the systems providing breathing air to the pilot. These systems are often treated as separate, but the events experienced are a result of the complex interactions of these systems, which, with the pilot included, are even more complex. Each flight puts extreme physiological demands on the pilot. The F-22 pilot community has come to consider a number of physiological phenomenon as a normal part of flying the Raptor, such as the difficulty in breathing and the Raptor cough. Acceptance of these phenomena as normal could be seen as a normalization of deviance. The NESC team found no evidence of a contaminant producing a toxic exposure. However, in any jet fighter environment, irritant compounds can be present. The F-22 has no effective filtration of breathing air or cabin air, which means irritant compounds could potentially enter the cockpit. The team found that the investigative process could have been more efficient. The F-22 task force was never given a directive that assigned the authority to conduct the investigation. They began with two narrow hypotheses and did not communicate well to all parties. The NESC team agrees with many of the Air Force's planned corrective actions and has identified a number of other areas for further consideration. These include both near- and long- term recommendations. Many of the NESC near-term recommendations are actively being addressed by the Air Force. For example, the upper pressure garment and oxygen schedule are currently being modified. Post-incident protocols to establish standard case definitions and treatment guidance will require some additional effort. Longer-term recommendations include conducting end-to-end testing of the life support system, environmental control system and air crew flight equipment. We also recommend a fundamental reassessment of the requirements for the life support system in high-performance aircraft and a formal lessons-learned review of the Air Force-led investigation. In summary, the NESC team acknowledges that the F-22 Raptor is a high-performance aircraft that is expanding the capability of aircraft performance. The Air Force task force has made great strides this summer in understanding the complex, highly interrelated nature of this problem. The NESC's independent analysis supports the Air Force plan of corrective actions. Thank you, Mr. Chairman. [The prepared statement of Mr. Cragg can be found in the Appendix on page 99.] Mr. Bartlett. Thank you all very much for your testimony. Before we begin, I ask unanimous consent that nonsubcommittee members, if any, be allowed to participate in today's hearing after all subcommittee members have had an opportunity to ask questions. Is there an objection? Without objection, nonsubcommittee members will be recognized at the appropriate time for 5 minutes. As is my usual custom in these hearings, I will reserve my questions until the other subcommittee members have had an opportunity to ask theirs. Mr. Reyes. Mr. Reyes. Thank you, Mr. Chairman. Gentlemen, thank you for your testimony. Let me start off this morning with the first question dealing with what the long-term impact may be on pilots that have flown the F-22. The testimony indicates that since pilots have been flying the F-22 since 2005 with all the same equipment that has now been identified as causing the oxygen problems that we have discussed today and previously, over time, this means that hundreds of pilots have flown the F-22. So the questions I have are the following: What does the Air Force know about any long-term health impacts from flying the F-22? Second, has the Air Force gone back and examined the health records of former pilots to perhaps look for clues on the impact? And third, does the Air Force plan to continue to research this issue and to track the health of current pilots? So whoever wants to take those first three questions. General Martin. Mr. Congressman, let me address that if I could as the Air Force Scientific Advisory Board considered those questions and in its recommendations presented the Air Force with some thoughts about actions it should take. First of all, with respect to the long-term effects of flying the F-22, because the Scientific Advisory Board did not conclude its work with root causes, it was not sure at that point whether we had contamination getting into the breathing air, which could have some sort of irritation or effect on the pilot, or whether it was the interaction that General Lyon discussed between the percentage of oxygen, the upper pressure garment and breathing cycles associated with the work of breathing. But it had no knowledge of long-term effects by reviewing pilots who had flown the aircraft before. It had no indications that the phenomenon that they experienced in the airplane had long-term effects. But nonetheless it, before returning to fly in September of 2011, had a battery of physiological samples, specimens taken from all of the pilots that would fly so that had you a baseline record of those pilots, who, of course, had not flown for 4 or 5 months, a baseline of their medical data, and as recommended, the Air Force establish a medical registry for all who fly the F-22 in case, as time goes on, there are things that are discovered that we would want to be able to go back and reference the conditions that may have changed within those pilots. But from the Scientific Advisory Board perspective, they were unaware and were not able to find any long-term effects for those people that they questioned but did establish a medical baseline for those people who are currently flying the F-22. Mr. Reyes. Having said that, it is clear, at least from just a layman's perspective of reading and listening to your testimony, that individuals are affected differently by the same. And I point out by way of example that according to some of the testimony that I reviewed, that pilots were expected to recover quickly. In some cases, the expectation was within minutes or perhaps hours after flying and being affected by this. But in reality, some plots took days to recover. So is that--is that a cause of concern that we have one expectation and the reality is completely different? General Martin. I think it is safe to say that the interaction that General Lyon discussed manifests itself in different ways with different people. Particularly depending on their breathing style and their blood saturation level, hypoglycemia, things like that. But from the Air Force Scientific Advisory Board perspective, since we did not know we had not discounted the potential of contamination, we were not led down the track of G atelectasis and other interactions that General Lyon discussed as aggressively because we were pursuing both hypotheses; one dealt with whether they are getting enough air, and the other dealt with whether they are getting contamination. And we had six sub-hypotheses for each of the major two hypotheses that we were pursuing at the same time. And I'll let General Lyon speak to this, but as they continued the path of contamination and ultimately have stated that it is unlikely that there's a contaminant problem with the F-22 OBOGS system and focused more on the physiological effects of high concentrations of oxygen, interference with the upper pressure garment and perhaps some other physiological considerations, that area is one that I think General Lyon could address more completely than I. Mr. Reyes. General. General Lyon. Congressman Reyes, if I may, when we returned to flying last September, General Martin's group gave us a series of protocols to put in place, to take blood samples and pulmonary function tests as a baseline for our Raptor pilots, which has been very helpful for us to be able to determine once they have had an incident, is there something which is resident in their body, something which has a lingering effect? That was mostly aimed at the potential contamination, of which we found none. But I should step back a second and mention that everyone who flies in an Air Force aircraft who is a rated officer goes through a medical screening to be qualified for flight. And we have annual physical health assessments that we go through that recheck our pulmonary function, recheck our medical baselines from urinalysis to blood samples, et cetera. Very rigorous. In fact, every year, that's the day that pilots and aviators look least forward to, is that trip to see the doctor, hoping they still come out cleared to fly, as they do. We have a very rigorous process for evaluating the health of our aviators. What we have found is, with our pilots who operate in harsh environments, whether it be high-G environment or high-altitude environment, there are additional protocols that need to be in place to understand the effects. High-G environments F-15s, F- 16s, F-22s, we learned in the 1980s that if pilots were not properly trained, educated and equipped with anti-G protection, they literally could knock themselves unconscious, and tragically, we have lost many pilots to G loss of consciousness. Years ago, the trend had increased significantly with that training, education, and the equipment we gave them. What we are finding is that with the maturing that we have of the F-22 weapon system, we have been flying it operationally since 2003, but a small number of aircraft, so the sorties, it takes a while to get to numbers. What we are finding is this reaction to the interaction between the equipment, the oxygen delivery schedule, and we get this Raptor cough, what has been referred to as Raptor cough. We can talk about that a bit more, but those effects typically clear up within minutes, if not hours, after flight. We have had a small number of pilots who have had incidents that have had lingering effects that go out to 48 to 72 hours. But within 72 hours, with treatment by our aerospace medical professionals, those effects go away. All of our pilots, all of our ground crew who have had incidents, physiological incidents, have been returned to duty and fit for flight status. Mr. Reyes. And I have other questions, Mr. Chairman, but in deference to the members that are here I will wait another turn. But I did want to finish up by asking you, so your position, your effective positions are that we do have a way to go back and ensure that if something develops in the future for these pilots, there can be a way to evaluate and analyze how it might have been impacted by the F-22. General Lyon. If I may, to close that out, one of General Martin's recommendations was to establish a medical registry of all F-22 pilots and associated ground crew. We have done that with this baselining of their pulmonary tests and with their blood tests. What we have also learned from our friends at NASA, from their expertise, is that there are other tests that we can put in place, which will give us greater understanding and depth of knowledge about pulmonary function. That is a recommendation which has been given to me to incorporate into our findings as we close out our analysis. Importantly, we know who has flown the F-22. We know who has been exposed to this environment. We have a registry of those people from the time that we have been flying and will continue to track them through their Air Force career and, if necessary, beyond. We have a moral imperative, we understand that, that if something is discovered that would be tied to this aircraft or in servicing this aircraft, we have a moral imperative to take care of those Americans. Mr. Reyes. I thank the gentleman. Mr. Chairman, I yield back. Mr. Bartlett. Thank you. As per committee rules, members present at gavel fall are recognized in the order of seniority on the committee; those appearing after gavel fall, in the order their appearance at the committee. Ms. Hochul. Ms. Hochul. Thank you, Mr. Chairman. I would like to thank you for holding this important hearing, first of all. I share the same view as everyone in this room, that our pilots' safety has to be one of our highest priorities. I know today we are primarily speaking about the F- 22 issue, and I have a closely related question. As we continue to invest in the F-35 Joint Strike Fighter, a program I do strongly support, is the Air Force aware of any problems or potential problems that are looming similarly to what we are experiencing with the F-22 with the F-35 program, is this something we have been proactive about and anticipating? General Martin. Ma'am, I would say the charter that we had in the Air Force Scientific Advisory Board was to review other military aircraft equipped with OBOGS systems and determine if there were some lessons learned from those aircraft that we could apply in the F-22 and, additionally, were there some lessons from what we learned in the F-22 study that should apply or could apply to those aircraft. With respect to the F- 35, it is an OBOGS system. It is manufactured by the same manufacturer. It has a little different scheduling activity. We have shared all of our information with the F-35 program office, and I would say that their system was designed with a bit more redundancy and robustness. It has a backup oxygen system that is installed on the seat with a fairly large quantity of air available to the pilot should the OBOG system have a problem. And we know of no physiological incident that has occurred in any of the F-35 flight operations to date, through the flight test as well as some of the training activities that are occurring down at Eglin. So to your question with respect to the F-35, we did review the system. It does have some differences, but it looks as if those differences are refinements and improvements over what the F-22 had, and we have shared the information that we learned with the program office and, as well, with the Navy and Marine Corps, who will be operating that airplane as well. Ms. Hochul. That is all I have, Mr. Chairman. I yield back the balance of my time. Thank you. Mr. Bartlett. Mr. Runyan. Mr. Runyan. Thank you, Mr. Chairman. General Martin, I am sure there is a classified answer to this, but specifically speaking to operating environment of the F-22, what really differs between that and say the F-16, F-15, F/A-18? What really sets it apart? General Martin. Mr. Congressman, I will let General Lyon discuss perhaps some of the warfighting characteristics of the operational environment, but from a system design and human systems integration perspective, the F-22, unlike all other aircraft, can operate routinely and in a sustained manner above 50,000 feet. Typically, the Air Force has required its air crews to use a full pressure suit when operating above 50,000 feet, even though the cabin pressurization is adequate and safe. Should there be a rapid decompression at those altitudes, the effect on the blood and the effect on your ability to properly inspirate or breathe is very, very challenging without supplemental pressure to keep your lungs from exploding and to ensure that you are able to process the oxygen that is delivered. The F-22 does not have a full pressure suit, and it was designed to operate with a partial pressure suit, the upper pressure garment, a different anti-G suit and those sort of things. So that airplane operates in an environment different than what we had operated. For instance U-2s, SR-71s, those airplanes, all of those air crew members fly in a full pressure suit. The F-22 pilots do not, and therefore, it is important they not only understand where they are vulnerable and the limitations of the equipment but also the performance of the equipment as they operate in those areas. So our concern was making sure that not only did we have the right equipment and that it would perform well and provide the protection that it was intended to, but that the air crews would also know what the differences were and how to operate in that environment. So from a physiological perspective and from a design perspective, that is the area of focus for the Air Force Scientific Advisory Board. With respect to the combat capability and advantages, General Lyon I think can best address those for that environment. General Lyon. Congressman Runyan, I have over 3,000 hours flying the F-16, and I can count the amount of time that I have spent above 40,000 feet in less than 10 hours. When I look at the operating envelope that our F-22 pilots go into every day, every day, they go above 40,000 feet. They operate at higher altitudes routinely than we have in the F-16 in the past and even than we did in the F-15. And they also operate in a very high-G environment. We have learned a lot over the last three decades about the impacts of operating in a high-G environment with our fourth- generation fighter legacy aircraft, and we have integrated those efforts into the F-22. We still learn today, after half a century of flying the U-2 at extremely high altitudes, we are still learning how to care for those pilots and continuously enhance their safety because of their exposure to very high altitudes. As General Martin mentioned, we have a partial pressure suit in the F-22. It is a truly a hybrid aircraft that combines high altitude and high G. And some of the equipment that we found that we have is optimized for one of those environments but not integrated to help with the other environment. That is one of the key points that came out of our analysis over the last year, is that we need to continue to do research on the science, the physiology of both high altitude and high-G flying, and the end-to-end integration and testing of all of the components that have really one thing in mind. That is to ensure that the proper volume of oxygen with the proper concentration of oxygen gets to the pilot so he has full cognitive skills and can handle the immense tasks that they have in an environment that we have not flown routinely before. Mr. Runyan. And I asked that question just to say we understand that we can change the physiology of a machine, but we can't change the physiology of a human being. We can push the threshold with technology all day long. And I think this a prime example of, we have spent a lot of money on developing weapons and tactics that are outside the envelope, but we are not going to be able to change the person that flies it. And I think sometimes as we step back and look at things like this, we really have to be cautious. I have the honor to actually sit on the VA [Veterans' Affairs] Committee, and the list you speak to, I don't want to really have to visit that--you know what I mean--especially with the Raptor cough and all that kind of stuff. I would just say that technology is great, but at the end, it is about the people. It is the men and women that do this that we really have to look out for. With that, Mr. Chairman, I yield back. Mr. Bartlett. Thank you very much. Ms. Speier. Ms. Speier. Mr. Chairman and ranking member, I really appreciate you holding this hearing. I am deeply concerned about this issue. And I must say, I don't have the confidence that we have come up with the answer yet. Let me start by asking General Lyon, there was an article that appeared today in the Dallas Star-Telegram, and I don't know if you have seen it, but it suggests that the Air Force knew about this back in 2000, that it declined a fix in 2005 that would have cost about $500,000 per aircraft. And that alone I think deserves your response. So if you would, please explain to the committee if you knew this back in 2000, if there was a fix back in 2005 that you declined to incorporate because of cost, which was at that time about $500,000. General Lyon. Congresswoman Speier, I will be happy to answer that question. During the engineering and manufacturing development phase of the F-22, we learned a lot. We had a lot of reports written about the status of different aircraft systems, subsystems, and how they interacted. And one of those reports was written in 2000 about the environmental condition system. Changes have been made since then. Changes were made based on that report. In 2005, when the report came out and suggesting yet a small incremental change that you describe to this system, the knowledge that we had at the time was that--the term Raptor cough didn't even exist at that time. We didn't even know it. We had some discussions about ear blocks, but we have discussions about ear blocks in other aircraft that we fly as well. So the determination in 2005 was what we knew about some of these interactions, is that they were at a small level, not widely spread, and we were still a very small fleet size at that time. It is as we have grown to the final delivery of our aircraft and really expanded the people who fly and the numbers of hours that they fly that we have gained a bigger understanding of what is going on. And we continue to make changes to this oxygen delivery schedule based on what we learn along the way. Ms. Speier. So the suggestion in 2005 has now been incorporated or has not? General Lyon. That suggestion has not been incorporated specifically. It was a minor modification to the ECS [environmental control system] system and the scheduling performance. We are looking at broader changes than that and making broader changes that envelop that one that was suggested then. Ms. Speier. But wasn't that suggestion to give the pilot the opportunity to control the oxygen flow? General Lyon. The pilot does. The pilot has a switch setting in the aircraft, an automatic setting, which is a lower oxygen concentration, and a maximum setting, which is a higher oxygen concentration. We have learned a lot about oxygen concentration. There was a period of time when we thought we may not have been delivering enough oxygen concentration. But what we have learned over the last few years is that there are these cases where the increased oxygen concentration does give some dryness. It does give some ear block, and it does create this Raptor cough, which is a temporary situation. Ms. Speier. Thank you. There has been some discussion about the fact that it is not just the suit, that those on the ground are also experiencing this condition, these hypoxia-like symptoms. Are you confident that the epoxy that is used in adhering the skin to the plane is not a contributing factor to this? General Lyon. Congresswoman, I am confident. We have done over 2,400 tests on the aircraft. And if I may have the picture of the testing locations---- Ms. Speier. Excuse me, I am running out of time. You have answered the question. Thank you. Let me move on to ask you whether or not the reports that you mentioned, one dating back to September, I guess, of last year, if those are going to be made public so that the findings and recommendations would be made available to the public? General Martin. The Air Force Scientific Advisory Board report has been completed. It has gone through its review, several tiers of reviews, and will be released today. And the findings and recommendations will be there. If I could, ma'am, I would make a comment that you will see in the report with respect to a better understanding of the interaction of this aircraft with the human operating the airplane, whether it be a maintenance technician or it be a pilot. In the 1990s, the United States Air Force, through its manpower reductions and its prioritization of effort, brought about by the downsizing of the military after Desert Storm, did not continue with the robust effort it had for decades before, its human systems integration, its aviation physiology. Ms. Speier. And you relied on contractors, correct? General Martin. Sorry? Ms. Speier. You relied on contractors as opposed to---- General Martin. In many cases. Flight medicine and aviation physiology research and development atrophied significantly during those years. And at a time when the airplane was going into a different environment that we talked about earlier, the people that would normally have done the testing and the evaluation and all of the things that we do to learn about those new environments were no longer in the military, no longer in our civilian workforce. One of the recommendations is that the Air Force reenergize its efforts with respect to human systems integration so that we will better understand some of the interactions that we are now learning about and actually, with the help of the Navy and with NASA, know more about today than we did a year ago. Ms. Speier. Thank you. My time has expired. Mr. Bartlett. Thank you very much. I will ask a few questions, and then we will return, for those who are interested, to a second round of questions. I would just like to return for a moment to my opening statement to make sure that a couple of statements there weren't misunderstood. I read and concluded that either the supply or the quality of the oxygen is contributing to F-22 pilots' hypoxia-like symptoms. I don't think those are the only two possible reasons for these symptoms. I was simply reporting what had been concluded. I didn't want this to be interpreted as a statement of fact. Next was the statement I made that the Air Combat Command had determined that the root cause of the F-22 pilot physiological issues is the supply of oxygen delivered to the pilots, not the quality of oxygen delivered to the pilots. This is what they concluded. I am not sure that is the correct resolution of the problem. I just wanted to make sure that people understood because I read those statements, I didn't read them as statements of fact, I read them as an account of what had been reported by the people who were investigating it. I hardly know where to begin. I spent a big part of my life in this area. And when I first came to work for the Navy as school physiologist in Pensacola, Florida, a great many years ago, they had just had an accident where the instructor and the student had penetrated a 10,000-foot floor and for several minutes were seen spiraling into the Pensacola sand. The commanding officer felt that there was a problem with the oxygen system. And since I was the physiologist, I was put on the Accident Investigation Board and we spent a very long time, as we appropriately do, looking at every aspect of this. Let me ask a few questions. The symptoms of hypocapnia, how early in your investigation were you cognizant of the fact that it was difficult to differentiate between hypocapnia and hypoxia? Hypocapnia is low carbon dioxide. If you sit and breathe deeply a number of breaths, if I sneeze three times, I have hypocapnia. I can feel the difference. I am dizzy. How far along were you in your investigation before you were cognizant of the fact that we ought to be looking at the symptoms of hypocapnia as well as the symptoms of hypoxia? General Lyon. Thank you for the question, Chairman Bartlett. We started to learn over the winter that there were a variety of symptoms that were emerging. And it was in April of this year where we had our restricted breathing working group that met, the combination of F-22 pilots and the professionals across the medical field, where we really got into substantial discussions about symptoms, as well as the research that had been done with Duke University by Dr. Mitchum and with the United States Navy, where we broadened our aperture and understood that these symptoms, like light-headedness, dizziness, fatigue, are actually ambiguous across things like toxic exposure, hypoxia, hypocapnia, hypercapnia, hypoglycemia, dehydration. But I would say for me as the task force lead, the ``aha'' moment came in April, when we got that full team of experts from different services, from NASA and from industry together. That is where it really started to emerge in our mind. Mr. Bartlett. How difficult is it to differentiate between the symptoms of hypoxia and hypocapnia? General Lyon. Chairman Bartlett, I tread on dangerous ground now engaging in a discussion with you with your level of knowledge about this. But what I have learned as the task force lead as I talk to professionals about this is that many of these symptoms are temporary. They emerge, and then they disappear. And it is hard to find any kind of DNA [Deoxyribonucleic Acid] trace that goes along with this. In fact, our protocols that have we put in place did not show any of these. So they are very temporary, and they come and go. So that has been one of the challenges. The other thing that they have told me is there is an individual variability factor here as well, that every human is a dependent variable if we think of this in terms of a test. And not only that, but from day to day, a human being is going to interact differently depending on how much sleep they had. Are they well rested? Are they hydrated? What are their blood sugar levels? So this understanding of the physiology and the science not only for, as Congressman Runyan was alluding to about the high altitudes and pushing the envelope, but just the basic physiology where we have let some of these skill set atrophy over the years as we downsized our Air Force during the post- Cold War period, that we were relearning old lessons. But in April, that is where it all came back to me. Mr. Bartlett. Is it not true that, in large measure, the symptoms of hypoxia and the symptoms of hypocapnia are indistinguishable? General Lyon. Mr. Chairman, in fact, that is what I found. I have to put things in fairly simple terms, and I asked them to give me a chart listing all of these different cases, hypocapnia, hypercapnia, et cetera, and then listing what are the symptoms. It looks almost like a complete ladder of Xs from left to right all filled in. They are almost a one-for-one match of symptoms across all of these various symptoms that we talked about in these causes. Mr. Bartlett. We have a very interesting dynamic here. If you think that you are hypoxic, the normal response to that is to try and get more oxygen. That is what you need, so you breathe deeper and maybe faster. And you can do that, and you will not be aware of the fact that you are breathing deeper and faster. And when you do that, you now drive down CO2 [carbon dioxide], and you create the symptoms of the thing that you were trying to avoid, that is hypoxia, because as you drive down the carbon dioxide concentration in your body, you have essentially exactly the same symptoms that you would have if you had a low oxygen concentration in your body. So now you begin a vicious cycle. I feel worse. I need to breathe deeper. You don't say that to yourself, but that is the physiological response to that. So now you breathe deeper. And the deeper and faster you breathe, the worse you feel. So you are kind of on a vicious cycle here. What partial pressure of oxygen do you try to maintain in the breathing mixture? I am going to ask a question, too, about Raptor cough and try to make sure that people understand where that comes from, that this isn't something evil and it is just a natural consequence of doing what you do in flying these aircraft. This is what happens. General Lyon. Mr. Chairman, we mean well above the useful consciousness requirement for---- Mr. Bartlett. We are roughly at sea level here. I think it is about 158, the partial pressure. And in our lungs it is diluted by CO2 and so forth, and it is down to about 100 millimeters of mercury. General Lyon. Yes, sir. Mr. Bartlett. Do we try to maintain the concentration of oxygen significantly above 158 millimeters of mercury? General Lyon. Significantly above it, in fact. We are approaching 90 percent, 80-90 percent pure oxygen at the higher altitudes that we fly. Mr. Bartlett. What happens when you have a very high percentage of oxygen in your lungs is if that oxygen is picked up by the capillaries in the lungs, there is nothing then--the nitrogen is gone. You have eliminated that by increasing the oxygen percentage. Ordinarily here, we have about 80 percent nitrogen. It just stays in there and holds the alveoli open. What you end up with is a situation like if you take two pieces of wet paper and put them together, you have to tug at them to get them apart. That is the surface tension of water. That is what happens when you have a very high oxygen concentration. You increase the probability--and I noted you were recommending that they go to max oxygen--you now increase the probability of atelectasis because you are driving down the concentration of nitrogen, so you increase the incidence of atelectasis. And that is an irritation, and you cough to try to open those alveoli up, and it could take quite a while to open the alveoli up, which is why it may persist for awhile. You all have done an admirable job of pursuing this. All of these instances occurred at two of your eight bases, is that true? General Lyon. Mr. Chairman, we have six permanent operating bases. Mr. Bartlett. And at how many of those did this occur? General Lyon. And your eight is correct. We have two forward present bases. Mr. Bartlett. So eight total. And it occurred in only two. General Lyon. Only two. Mr. Bartlett. Which is another indication that what is happening here is not a problem with--and this is a very complex relationship between the pilot and his system. Pilots are taught early on that they can't really trust their senses. You have cockpit signals that tell you what is up and what is down, and you have learned to trust those rather than the seat of your pants, because you really can't trust that. And all of you have been, I gather, how many times do you go in that altitude chamber and they ask you to take off your mask? And you take off your mask, and you are doing something like writing something, and you think you are doing just fine. And then you put your mask back on, and you look at what you have done, and wow, how could I have done that? There is little perception that you are becoming hypoxic. And you think that you are doing just great, and the better you feel you are doing, the worse you are doing. So the pilots have learned that they can't really trust their senses. They have got to trust other things. I am really pleased that you put two things in this system that now pilots can look to. One is an oximeter on the ear now, I gather, that tells you what your oxygenation is in your blood. If that is up, you have got enough oxygen. No matter how you feel about it, you have got enough oxygen if that is up. I think you also put a sensor in that tells them what the percent oxygen is in their delivery system? General Lyon. Yes, Mr. Chairman. Mr. Bartlett. There needs to be a protocol that keeps that as near 158 as you can. If you run it much above that, you are going to increase the incidence of atelectasis. And this kind of breeds some perception that there is a problem with the airplane or a problem with the oxygen system or something if you have atelectasis. It is not a problem with either, it is just a fact that if you are breathing a high percentage of oxygen and pulling Gs, which is going to exacerbate the thing, that you are going to have more atelectasis. Well, I have asked enough questions for the moment. Let me turn to Mr. Reyes for his questions. And we'll come back. Mr. Reyes. Thank you, Mr. Chairman. Listening to the chairman, I was wondering, you know, we first deployed the F-22 in 2005, and it wasn't up until 2008 or so that these problems started to surface, so I am wondering what explanation is there for this time lag? Were the problems there all along and just not being reported, or did you change the operational, you know, operational capability--not capability but the operational environment of the F-22 that brought upon the pilots this problem? General Lyon. Thank you for that question, Congressman Reyes. After a few years of operational flying, we started to get a large number of aircraft, a larger population. We get into the individual variability of the pilots who were flying. And in 2008, we had several incidents. One of the things that was informative to me from Mr. Cragg's independent analysis was this thing known as the normalization of deviance, which was learned from their studies that they have done on some of their safety and engineering studies for things which have occurred with NASA in the past. There was an acceptance early on by the Raptor pilots who flew this aircraft that it is a littler harder to breathe than it is in other aircraft. And they were taught that it is a little harder to breathe, and they began to accept it. But over time, as the pool of pilots got larger and we flew more, we started to see some of this individual variability come into play. And then we had some incidents, and we really started focusing on it. What was also helpful for me as I worked through this analysis was looking at the Air Force's history in another aircraft, the F-16. The F-16 flew operationally for 4 years before it had the first G loss of consciousness [G-LOC]. Same capabilities in the aircraft; same G available, the same qualification and criteria to get into the aircraft. But we flew for 4 years. And I asked myself, why? I still don't have an answer as to why it took 4 years for G loss of consciousness to become an issue and then continue on for awhile. But it is not uncommon from what I have seen in some case studies to fly aircraft for a number of years, very selective pilots and aviators at the very beginning part, very controlled environments, but we start to broaden the aperture and bring more folks in, and we start to see more variability over time. Mr. Reyes. The other question that comes to my mind is we are dealing with the F-22 in this hearing, but are there lessons to be learned as we transition to the F-35? Does the F- 35--do we anticipate that it is going to have similar issues, or the fact that we are working our way through finding solutions for the F-22, is that going to be beneficial for the F-35? General Martin. Congressman Reyes, I would say this, that the F-35 oxygen system is more robust than the F-22 in terms of its design and redundancy. The formula that it uses for computing the percentage of oxygen is slightly different. And from the lessons we have learned with respect to connections, potential for leakage, and of course the emergency oxygen system, they have applied those lessons in the F-35. As General Lyon has indicated, that will not stop all potential hypoxia-like incidents or hypoxia incidents due to hyperventilation or other things that could occur. But in terms of the design, it seems as if the F-35 has gone to school on the F-22. And of course, both with what General Lyon's team has done and with what the AFSAB did, we have shared all of that information. In fact, during the early part of our study, NAVAIR systems people were fully integrated into our effort and shared with us the lessons they had learned in OBOGS in general and where they were with the F-35. So we are doing our best to make sure what we have learned here will apply to the training and to the design and operation of the F-35. Mr. Reyes. Thank you. And I have some other questions, but I will submit them for the record. Mr. Bartlett. Thank you. Ms. Speier. Ms. Speier. Thank you, Mr. Chairman. Mr. Cragg, I was particularly struck by the statement in your report that reads, the acceptance of these phenomena as, quote, normal could be seen as, quote, normalization of deviance, that the F-22 has no effective filtration of breathing air or cabin air and although no conclusive evidence has been found indicating the effect of irritant compounds, they could enter the cockpit and the pilot's breathing air supply. Could you comment a little more on those statements, please? Mr. Cragg. Sure. Thanks for the question. NASA is very familiar with the term ``normalization of deviance.'' It is when we get to a position where we accept the operation of some system or component that is not operating properly, and we start treating it as that is the way it normally is. And the best example from NASA's perspective was the foam coming off the external tank for the shuttle. It happened since the beginning, and we came to accept it as a normal part of doing business, but it wasn't. And we should have fixed it long before. So when we began examining the F-22, things like the Raptor cough, things like the pilots going home at night being physically exhausted, said to us, there is something that may fit into this category of normalization of deviance. So we wanted to point that out. It is a way that you can almost fall into that type of a mind set if everybody says it is normal, and especially with the F-22 being the top of the line Air Force fighter, when people say, do you want to fly this fighter? Yes, yes, of course, I do. There are some things that are different about this; it is harder to breathe, but the pilots just apparently didn't care. They wanted to jump in and begin flying it. So the normalization of deviance is a cultural thing that I think the Air Force needs to take a look at and help prevent from occurring in the future. Ms. Speier. And your reference to this filtration system and the fact that these toxic compounds can get into the oxygen system, could you comment on that? Mr. Cragg. We began our review by trying to double-check some of the things that we understood that the Air Force had already done. One of the things they looked at quite extensively was the contamination issue. So I had my people examine all of the evidence, the data, and we came up with a conclusion that we found no contaminants that were getting into either the breathing supply or the cockpit that would cause a toxic condition for the pilot. Having said that, during that examination, we found that the air coming into the cockpit and the breathing supply is not filtered. And so, it is not filtered, which would put the pilot in a position where he is breathing air like in any jet fighter environment. There are irritant compounds. There is potentially some exhaust gases that the individual may be breathing. We wanted to highlight the fact that the onboard oxygen generator is not a great filter. It is filtering a lot. Some of the cabin air that is coming into the cabin is being filtered by what is called coalescer socks. But we wanted just to point out that the air coming in is not completely pristine. Ms. Speier. Are you suggesting that it should be completely filtered? Mr. Cragg. No. No. Ultimately what we are suggesting is that some of these irritant compounds could potentially cause a pulmonary problem or a restriction of breathing. One of the members of my team is from the EPA, who has done testing with irritant compounds and has found that to be the case in some individuals. It is highly an individual response to that. Ms. Speier. Two more questions I want to try to get in in 42 seconds here. The Air Force has said that none of the hypoxia incidents have resulted in long-term or lingering physiological effects. But a medical expert wrote in Flying Safety Magazine that a pilot who experienced these symptoms was restricted from flying for several days. Wives of pilots have also described what they believe to be long-term or lingering effects, and many of these pilots describe blackouts and memory loss when they experience symptoms. Some pilots also describe experiences of vertigo weeks later. To what degree do you think that we need to look at biomarkers as part of this evaluation? Mr. Cragg. I think that is a very good question. I had two NASA flight surgeons on my team, and they did some extensive review of what the Air Force has done. I would not like to speak for them. I wanted to make sure what we put in our report as far as the medical portion was exactly correct, so I ensured that that portion of our report was thoroughly peer-reviewed by other flight surgeons. So if you don't mind, ma'am, I will take that one for the record, and I will provide you an answer. [The information referred to can be found in the Appendix on page 105.] Ms. Speier. I appreciate that. One last question. Have any of the pilots declined to fly the F-22 because of what has transpired? General Lyon. We have one pilot across the entire F-22 enterprise who is currently not on flying status based on his request. Ms. Speier. Thank you. Mr. Bartlett. Thank you very much. Mr. Reyes mentioned G-LOC; this is the unconsciousness you get when you are pulling Gs. And this is due to an apparent design defect in us. Essentially, every other part of our body has the ability to accumulate an oxygen debt, which is why you keep breathing, huffing and puffing, after you run hard. Our brain has zero ability to accumulate an oxygen debt. So the moment it doesn't have enough oxygen to operate, it just quits operating. And we try to avoid this, of course. When you are pulling Gs, the blood, by centrifugal force, it is taken down to your legs and abdomen. And we try to avoid this by anti-G suits, something that as soon as you start pulling Gs, they start squeezing on your abdomen and your legs to make sure that the blood can't pool there. But you can't always do enough of that, and sometimes the blood still may pool there enough that you get some transience. I have no idea why there is that design defect. You would think that ought to be built in. If anything needs to work all of the time, it is the brain, isn't it? But if it doesn't have enough oxygen, it just quits. Ms. Speier mentioned vertigo weeks later. I was just thinking, unless there is some pollutant in the oxygen, and I think you pretty much ruled that out with all of your testing, there is just nothing that can happen during flight, hypoxia or hyperventilation, that is going to--you might better look to what he did last night than look at the hypoxia or the hypocapnia that he experienced 6 weeks earlier. I have a series of questions that we would like to get answers to. Let me ask you, first of all, is there any evidence, other than circumstantial, that there was ever an hypoxic incident? General Lyon. Mr. Chairman, if I may lead and then if General Martin would like to add. One of the things that we found is that early on, the discussion centered on hypoxia, and then the discussion became hypoxia-like. But in the end, what our analysis said is these are physiological events, which get back to the things that we described a little earlier today that get into physiology. Physiological events is the umbrella, of which hypoxia is one of the parts of that. But most of these events are so ambiguous, and these multiple factors, that we didn't have the science early on when we had these incidents to really plumb to the depth required to determine hypoxia from exposure to compounds to hypoglycemia, et cetera. It is only through the protocols and the learning that came out of General Martin's efforts that we have been able to understand these incidents in more depth over the last year, that have allowed us to rule out things like contamination as a root cause for what was happening to our pilots. And we start to see that it is these breathing restrictions and breathing impedances, as you referred to, which can lead to hypercapnia or hypocapnia or similar type events for restricted breathing. But that is where I end the analysis with my conclusions, after I have taken all of the findings that have come in from the other bodies and looked at this in total. They are not hypoxia, per se. A small number of them are hypoxia. We have had some pilots who have had interruptions in their pilot supplies, and we have tracked that, and we have noted that. So we do know that if there was an interruption, a malfunction, that they will get less air and they will, indeed, become hypoxic. But most of what we have been studying, what we have been concerned about, are the instances where there was no explanation at the time, and they do not lead you to hypoxia. General Martin. During our review of the cases and after we initiated the return to fly phase, where we had the finger pulse oximeter, there were--we had data that seemed to correlate with the symptoms and the physiological presentation of what you would call hypoxia. For instance, a pilot cruising out through 15,000 feet began to sense his hypoxia symptoms, began to feel somewhat light-headed, looked at his pulse oximeter and saw that it was at 85 percent or 83 percent. As we went further into the data review over a period of months and gathered more data and became much more conversant with the strength and weaknesses of a tool such as that, we found that oftentimes what seemed to be a correlation turned out to be what the medical world refers to as artifact data or data that was not accurate. And we did not know at that time that perhaps the best indicator of whether the oximeter was working properly or not was the pulse. And if the pulse went away, then the oxygen dosage or the oxygenation number may not be accurate. So we thought we had some fairly representative samples of someone not getting the oxygen that they needed to perform without impairment and their symptoms. And it turned out that in almost every case, that data was inaccurate. Hence, the pulse oximeter that will go in the head because the extremity is the last place that the body is going to push the blood when necessary to preserve function of the brain and the core of the body. So we should get better data with this, but still there will be some artifact data just based on the technology used to measure. I have no doubt that some of the cases that we reviewed, that the pilot believed that he was suffering from hypoxia; but it may not have been hypoxia, it may have been the symptoms that were similar. And those are the symptoms that he or she felt in the physiological training unit. And when they went to high altitude, and one of the cases that you mentioned, not only do we do some exercises, but we are supposed to mark, if you will, perhaps a narrowing of the vision, perhaps a loss of color, perhaps a dizziness, perhaps a light-headedness, perhaps other symptoms. We are supposed to note that so if we felt that in the aircraft, then we would immediately go to 100 percent oxygen and recover the aircraft. I have no doubt that there were air crew members or pilots who experienced those same symptoms, but we can't prove that it was due to a lack of oxygen from the OBOGS system itself. Mr. Bartlett. Are we now acquainting our pilots with the similarity and the symptoms between hypocapnia and hypoxia? General Lyon. Mr. Chairman, indeed, we are. In fact, we have visited five of the six permanent location sites. The one location they are deployed currently, so we haven't been out to see them. But we have pushed them the information. Where we have shown them the results of the centrifuge and altitude chamber training, that was my next ``aha'' moment in about the May-June timeframe, where we, for the first time, put F-22 pilots, wearing their F-22 flying ensemble, into ground testing and altitude chambers and centrifuges, and we measured that the system was not performing the way we thought it had been performing over years. We have advanced the state of testing and our ability to understand what the oxygen delivery is. We have shown the results of that to the pilots. In fact, 2 of the first 12 pilots who did centrifuge testing replicated their hypoxia symptoms on the ground in a centrifuge inside a closed building. That was an ``aha'' moment for me that really started to point toward one of the factors. As you rightly pointed out, Mr. Chairman, it is more than one factor. But one of the factors is this restriction in breathing or impedance in breathing, which can come--the restriction from the upper pressure garment, and the impedance from the C2A1 filter, which we have been flying with for a period of time to protect against the possibility of contaminants, and also the pressure drops that the Navy helped us with, in understanding it and NASA affirmed it. The pressure drops that occur inside the cockpit as the air flows through the oxygen hoses and the quick connects; we had measurable, objective data, and we have shown it to our pilots. And they are aware of that. We have not had an incident since the 8th of March this year, over 6 months ago. This is longest period without a physiological unexplained incident in years. Mr. Bartlett. Did you have an increased incidence of these events when you had the filter in? General Lyon. Mr. Chairman, we did. When we returned to fly September of last year, we put a number of measures in place to protect our pilots, to ensure their safety, to enhance their safety. And some of these things we put in place actually increased the incidence. One of the measures that we put in place was guidance from me to the entire F-22 fleet that said, at the first sign, the first symptom of anything, you are directed to terminate your mission and come home. We injected a sensitivity because safety was paramount in our mind. And they responded to that. And they did safely recover every aircraft each time that we had an incident. But I marked my guidance as the Air Combat Command Director of Operations with their safety as paramount, to come home and terminate it, that we have injected an increase in the incident rate during that timeframe. Mr. Bartlett. Yeah. I would have predicted an increase in the reported incidents if you put a noticeable resistance in the line because the response to that is, gee, it is hard to breathe; I am not getting enough oxygen; I need to breathe deeper. So when you do that, you create hypocapnia, and you create the symptoms of the things that you are trying to avoid, don't you? General Lyon. Mr. Chairman, you are exactly right. And to also dovetail off of what Mr. Cragg has said, when we put this canister on pilots and told them to fly with it to protect them in the event of contamination, what we failed to tell them was this known breathing impedance. We knew about the breathing impedance. What we didn't know was about the restriction in breathing that came with the upper pressure garment. And the combination of the restriction from the upper pressure garment plus this impedance we believe is what in this individual variability sent a number of our pilots beyond their normal physiological limits to where they saw these first symptoms. Mr. Bartlett. Let me quickly go through some questions that the staff wants to make sure we have on the record so there is no misunderstanding in the general public about the intensity of our effort to solve this problem. You don't need to give a full answer here. You may give a more complete answer for the record, if you wish. In your findings, you cite a number of failures in F-22 modeling and simulation of the F-22 life support system. Do you believe engine-to-mask modeling and simulation, dynamic response testing across the full range of simulated environments, statistical analysis for analyzing and predicting system performance and risk, and OBOGS performance when presented with a full range of ECS air contaminants should be accomplished for the F-22 program? I guess a simple yes or no is okay. General Martin. Yes. Mr. Bartlett. What causes what has become known as the Raptor cough? How frequently is it experienced by the average F-22 pilot, and how serious an experience is it for the pilot? Does the Raptor cough have any long-term effect on the pilots? Do you think the record needs any more than what we have discussed? General Lyon. Individual variability, there is no standard number of events. Some individuals don't have it at all. Some have it more than others. And we have no indication of long- term effect. Mr. Bartlett. You will reduce those incidents if you keep oxygen as low as is feasible, right. The blood is oxygenated not because you push a lot of oxygen pressure into it, because it has got hemoglobin, which carries blood. The amount of oxygen that is carried in the blood by solution in the blood is very small. So any time you get over 158 millimeters of mercury partial pressure, you are minisculely increasing the amount of oxygen available to the tissue, but you are considerably increasing the probability of atelectasis. Is there any linkage between hyperventilation and the Raptor cough? I was trying to think of--can you increase the Raptor cough atelectasis by hyperventilation? General Lyon. We have not made that linkage yet. Although what we have mentioned is one of the institutional things that we will continue to work on is further study of this man- machine interface, not only for the F-22 but for other aircraft. Atelectasis and the Raptor cough, there is relationship between the two. Mr. Bartlett. Of course. That is why you have the cough. How thoroughly did your study group examine this issue, and does your report draw any conclusions or make any recommendations to address the Raptor cough issue? Is there any modification to the F-22 oxygen system that would minimize or eliminate the Raptor cough and its effect? I will answer my own question. If you keep the CO--or the oxygen level as close as you can to 158 millimeters of mercury, where your blood will be adequately oxygenated, you will reduce the incidences, I think. As you fill the lungs with more and more oxygen and less and less nitrogen is there to hold the alveoli open, you are going to increase the incidence of that; am I correct? General Lyon. Yes, Mr. Chairman. May I add one thing for the record, one of the reasons we are significantly above 158 is for protection against the possibility, however slight, but the possibility of rapid decompression at high altitudes. As you know, super-oxygenating the bloodstream will maximize our time of useful consciousness, should we have that take place. Mr. Bartlett. There is a press report this morning indicating that the Air Force medical experts linked the Raptor cough to the F-22's air supply system. I would hope so. The article indicates that the Air Force decided in 2005 not to make a fix to the F-22 oxygen system. Do you know if a modification to the F-22 air supply system was considered in 2005 to address the Raptor cough issue and why the modification was not made? General Martin. Sir, let me give you a partial answer here. First of all, the bleed air satisfies many customers. It satisfies the cooling requirements for the flight control computer. It satisfies the communication navigation cooling system. It satisfies the fire control system. It provides pressurization to the cabin. And it also provides the pressurized air at a specific pressure and temperature to OBOGS, which then delivers breathing air to the pilot. It is controlled by a node, known as the air cycle machine, which meters the amount of air necessary to the customers, based on the pressurized air coming in as well as the temperature. If the temperature begins to creep up, which at high-altitude, low-power settings, it does, it then begins to shut down the delivery of the air to some of those customers down range, and the OBOGS is one of them. At that point, then, there is a restriction to the amount of air the pilot might get, to include zero, when the OBOGS has no pressure at the front. We knew that in the early testing, and there were modifications to the air cycle machine's algorithms that controlled the metering of the air, and that, again, was brought forward in the 2005 timeframe as a part of the discussion there. As a result of the SAB study, the program office has gone back into that algorithm and adjusted it again, because the number of ECS rollbacks or shutdowns was greater than predicted or expected, and they have tried to adjust that air cycle machine mechanism to reduce the number of shutdowns that would occur, therefore, shutting off the oxygen to the pilot. Further, as you know, from what General Lyon said, there will be a backup oxygen system placed on the aircraft so that if that happens, you will still get breathable air from the backup system that will be much larger than the basic emergency activation system we have today. Mr. Bartlett. In early designs of the F-22, didn't we have a backup system, and wasn't it taken out to reduce cost? General Martin. It was not a cost issue, sir. It is true that it was taken out. It did have an initial design of a backup oxygen in addition to the emergency oxygen system. A series of events occurred, but the catalyst for this particular decision was the term that every aircraft goes through, the war on weight. After the prototypes had flown, they then begin to go into their engineering, manufacturing, development phase. And at that point, you begin to find out where the strengths and weaknesses are. The aircraft always gain weight. When it gains weight, it may not be able to pass its key performance parameters of sustained G or acceleration or altitude or whatever. So, at that point, they had to get the weight down. The difficulty here was that as we went into acquisition reform, we created the IPT [Integrated Product Team] structure, and at that point, very tough decisions were made in terms of who had the authority to make certain decisions. That usually was generated as a result of a very conscientious review to determine where your safety-of-flight critical items were. And as the program evolved, the backup oxygen system, the OBOGS and the emergency oxygen system were not considered safety-of- flight critical. They were safety significant, which meant that the decision to take the backup oxygen system off could be made at a lower level than the chief engineer of the F-22, and it was. And it was not known at that time by the senior leadership that that--the analysis that went into that trade study that allowed the backup oxygen system to come off. In retrospect, that was not an appropriate decision. But at that time, that is what the decision was. Now that decision was made also with the information that the environmental control system, ECS, IPT was going to put a shunt valve in that would always ensure there would be positive pressure to the OBOGS, and therefore, taking the backup system off would not be a problem, given that you had an emergency backup system should the OBOGS fail entirely. So what looks like what I would consider to be a flippant decision turned out to be steeped in data and very well thought out, but it was perhaps not viewed by the more experienced and senior engineer responsible for the F-22. Mr. Bartlett. If weight is that critical, what do we prune now so we can put it back in? General Martin. Sir, first of all, it was 15.4 pounds, as I recall. And they were looking for every pound they could find. The performance of the aircraft is so magnificent that 15 pounds is not going to hurt this aircraft. Mr. Bartlett. Is there any explanation of why the reported hypoxia incidents have been concentrated at only two of the six operating bases? General Lyon. We asked the Air Force Safety Center, Mr. Chairman, to go to all of the F-22 bases and talk to the crews, the air crew and the ground crew, to help us understand some of the factors beyond what I would call hard science, beyond engineering science, and get into the human factors. One of the locations is Joint Base Elmendorf-Richardson, where tragically, in November 2010, Captain Jeff Haney lost his life. And there was a cluster of incidents that took place in May 2011, just before the standdown occurred. There is a residual effect within the community that occurs when you suffer through a tragedy. And as General Martin mentioned earlier today, there was a period of quite some time, nearly a year, uncertainty about what caused Captain Haney's crash and the loss of his life. So this built up and manifest inside the community, and there is residual effect that has come from that. At the other base, Joint Base Langley-Eustis, we found that there was a set of factors there where the C2A1 canister--and I can tell you from my discussions with all of the wings, the C2A1 canister had a different meaning at that installation than it did at the other five. And we saw several clusters take place. And the human factors engineers and scientists tell us that this is to be expected, that if there is a perception of a problem, and somebody credible within the organization has a problem, others will begin to experience the same thing. And that is what we had; credible aviators who had a perception that we had helped them believe, there is a problem with your life support system which could have been contamination, and at the first sign, saying, I have a problem, terminating the mission. Their credibility extended to other people at their installation. That is how we explain it. At the other installations, they never got to that point. But there were factors resident localized that had professionals make well-measured, good decisions to terminate missions because they had the perception that there was a problem. General Martin. One other comment, Mr. Chairman. When the Scientific Advisory Board recommended the return- to-fly protocols and the steps to be taken, it knew or it believed that it would be important for us to continue the return-to-fly process until at least March of 2012, because that would give us a fairly representative sample across the fleet of the different seasons. It also turns out that at Elmendorf and at Langley, those two bases fly with the protective gear for winter operations, which means if you haven't readjusted your upper pressure garment and you now fly with more stuff, the restriction to the breathing could be greater. And the incidents may very well have also been related to the fact that we didn't have a proper standard for the upper pressure garment fitting, and then we didn't change the upper pressure garment fitting when we put on the rubberized and cold-weather gear. Mr. Bartlett. Thank you. General Lyon, I think you probably have articulated the major reason for this. A little anecdote may help put that in perspective. If you are provided a breathing mask and you are sat behind a screen and you are getting your air supply through a tube and you are told that, by and by, you will smell violets and you are supposed to indicate to the investigator when you smell violets, essentially everybody will smell violets. The investigator has not done one thing to the air supply. These are very subjective things, and it is kind of tough for us to recognize that we are not in full control of these things. But these are very subjective things. And if you think that there is going to be a problem with your oxygen supply system and you may become hypoxic, the least little thing will trigger this hyperventilation, unperceptible to the pilot, and he will then have exactly the symptoms of the thing that he dreaded, and that is hypoxia. It is a very interesting thing that has happened here, and I am sure that this was a learning experience for everybody who was involved in the investigation. Is there an explanation--why do you believe that the pilots have not previously complained until recently about the chest constriction caused by the upper pressure garment now determined to be a causal factor in the F-22 physiological problems? I am not sure, my statement seems to imply it was a causal factor. Do you think there is any causal factor other than the fact that the perception was, gee, my breathing is impeded a little and I guess I need to breathe more to get oxygen. And so they end up breathing more and get hypocapnia, which are exactly the symptoms of hypoxia? Is there another explanation? General Lyon. If I have the question correctly, and I am not sure I do, Mr. Chairman, how did they go for so long with this upper pressure garment filling prematurely, restricting their breathing and not knowing it, this is--what helped inform us was the normalization of deviance that Mr. Cragg has mentioned. When we put these F-22 pilots into the centrifuge with their gear on and they were accelerated to high G, we measured the fact that they were prematurely filling and restricting their breathing, and then we were able to measure, if we could have the chart that shows--as you can see on the chart in front you, Mr. Chairman, that without the upper pressure garment on, the tall blue spike shows how quickly they can inspire and get the required volume and that the red line shows that with the upper pressure garment on, they cannot get the depth that they need, and it takes longer to breathe. And as you already mentioned, Mr. Chairman, the brain just does this without the pilot knowing perceptibly that he is changing his breathing. This is what we have come to know, which the Navy helped us with, this understanding of the work of breathing. Breathing restrictions integrated into the pilot's flight ensemble, forced them to work harder to get the required volumes of air, which can then lead to fatigue symptoms over time. Mr. Bartlett. When I got my doctorate and its emphasis was in this subject 60 years ago, I never dreamed that I would be sitting here at a subcommittee hearing where this information would be relevant. Do all other fighter aircraft have a backup oxygen system? General Martin. Could you repeat that question, sir? Mr. Bartlett. Do all other fighter aircraft have a backup oxygen system? General Martin. Sir, they all have an emergency oxygen system, and they either have a backup oxygen system, or they have a plenum, which is like a reservoir that gives them additional air should the OBOGS system fail. Mr. Bartlett. Thank you very much for staying here through a very long subcommittee hearing. I hope that this puts at ease the minds of our pilots and their families. Thank you for doing a great job of investigating this, and thank you for your testimony today. [Whereupon, at 12:00 p.m., the subcommittee was adjourned.] ======================================================================= A P P E N D I X September 13, 2012 ======================================================================= PREPARED STATEMENTS SUBMITTED FOR THE RECORD September 13, 2012 ======================================================================= [GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT] ======================================================================= WITNESS RESPONSES TO QUESTIONS ASKED DURING THE HEARING September 13, 2012 ======================================================================= RESPONSE TO QUESTIONS SUBMITTED BY MS. SPEIER Mr. Cragg. The NESC Team report has described recommended medical courses of action for pilots who experience prolonged symptoms, based on what the NESC Team believes is the reason for these symptoms. Beyond that, the identification of precise biomarkers in hypoxic-ischemic injury in general, e.g. in victims of stroke, is still very much in the research phase, and not yet suitable for general diagnostic use, as in this case. [See page 26.] ? ======================================================================= QUESTIONS SUBMITTED BY MEMBERS POST HEARING September 13, 2012 ======================================================================= QUESTIONS SUBMITTED BY MR. BARTLETT Mr. Bartlett. What have been the physiological consequences to the pilots in the reported hypoxia incidents? Have you categorized each of these incidents in terms of level of seriousness of the reported event? If so, what does the data show? General Lyon. There have been no long term physiologic consequences to pilots that have reported hypoxia incidents. Four pilots were treated in hyperbaric conditions due to the nature of their medical complaints. All pilots who reported hypoxia incidents have been medically returned to flying status. Level of seriousness is generally categorized by mishap/incident class. Classes of mishaps range from Class A (the most serious) to Class E (the least serious). Pilots who have reported hypoxia have categorically been Class E incidents. The data shows there have been no biomarkers found in the aircraft or pilots pointing to contamination in the breathing gas. Mr. Bartlett. What are the operational impacts to the current restrictions on F-22 operations? Are F-22s capable of operating throughout their full operational envelope if required to do so? General Lyon. F-22 aircraft are currently restricted to 44,000 feet during training missions with limited operational impacts. If required to do so, F-22 aircraft can operate throughout their full operational envelope. Mr. Bartlett. What is the status of actions on recommendations of General Martin's Aircraft Oxygen Generation Study Group? General Lyon. The Scientific Advisory Board (SAB) made a total of fourteen (14) recommendations; eight (8) short term and six (6) long term. The Air Force has completed seven (7) of the eight (8) short term recommendations. The remaining short term recommendation for Helmet Mounted Pulse Oxygen (HMPO) is on schedule to be completed in December of 2012. The six (6) remaining long term recommendations are on track for completion by the end of FY 2015. Mr. Bartlett. Is there a cost and time estimate to institute the planned actions to the F-22 life support system? General Lyon. Acquisition efforts are underway that include an Automatic Backup Oxygen System (A-BOS), Automatic Ground Collision and Avoidance System (AGCAS), Upper Pressure Garment Valve, Oxygen Hose Pass-Thru Panel, and Helmet Mounted Pulse Oximeter. These efforts are estimated to cost a total of $82.5M to develop and install on the entire fleet of F-22 aircraft. Mr. Bartlett. On what basis was the F-22 returned to flight in September 2011, since the Scientific Advisory Board and your Study Group had not completed their work? General Lyon. The Commander, Air Combat Command tasked ACC/A3 to implement the SAB study group's recommendations and to return the F-22 fleet to flight operations in late August 2011. The SAB study group's recommendations were: 1. Incorporate additional aircraft life support inspections and modifications 2. Standardize OBOGS equipment to the ``-109'' configuration 3. Implement an OBOGS ground-based maintenance inspection procedure 4. Modify pilot life support equipment to incorporate the use of the C2A1 chemical warfare filter 5. Implement new post-incident medical and logistics protocols 6. Collect medical baseline blood samples for pilots and selected maintenance personnel who perform engine ground-run tests 7. Conduct baseline pulmonary function tests for pilots 8. Incorporate finger-mounted pulse oximeters into aircrew flight equipment 9. Eliminate the 25,000, mean sea level altitude flight restriction 10. Communicate the results of the investigations, testing and the advisory board's findings. In addition, Air Combat Command directed F-22 units to accomplish life support academics, emphasized oxygen delivery/life support emergency procedure training, and initiated guidance that directed pilots to terminate flight operations at the first sign/symptom of a physiological event. The F-22 community resumed flight operations on 21 Sep 2011 after the Secretary of the Air Force approved the F-22A ``Return to Fly'' Plan. The plan integrated the collective inputs of the operations, logistics, medical, safety and advisory board disciplines that had investigated the F-22 over the previous 3 years. The determination to resume flight operations balanced the current understanding of risk and the operational imperative to retain the readiness of the nation's Air Dominance fighter fleet. Pilot combat mission readiness skills are a perishable skill set. Some skills are retained through the use of flight simulators, other skills are not. Emerging insights from the 16 Nov 2010 fatal mishap--insights delayed by the inability to excavate the crash site until the summer thaw in Alaska, new inspection criteria for F-22 life support system components which ensure the veracity of the components, testing which began to eliminate ambiguities/uncertainties of previous physiological incidents; all coalesced to permit a thoughtful calculation to resume flight operations. Mr. Bartlett. What is the status of the Air Combat Command's Life Support Systems Task Force report, and when will it be released? Would you provide the committee a copy of the report when it is completed? General Lyon. The LSS TF final report is currently in draft with an estimated completion date of 31 Oct 2012. The report will be vetted through Headquarters Air Force and be available once released by Air Force leadership. Mr. Bartlett. We understand that the upper pressure garment was also used in F-15s and F-16s from the early 1990s through 2005. Why weren't vulnerabilities in the upper pressure garment determined while it was in use with the F-15 and F-16? Are there differences in the upper pressure garment system in the F-22 compared to the F-15 and F- 16? General Lyon. The Upper Pressure Garment (UPG) system being used in the F-22 is fully functional, compatible with, and meets all requirements for use with F-15 and F-16 aircraft. The physiological root cause investigation concluded the UPG was prematurely inflating due to the F-22's safety positive pressure breathing system. Neither the F-15 nor F-16 has safety positive pressure breathing systems. Mr. Bartlett. Why have ground maintenance personnel experienced symptoms if the issue is primarily linked to life support systems inside the cockpit? General Lyon. All ground incidents which occurred between 22 Sep 2011 and 14 Dec 2011 were extensively investigated. All ground incident aircraft underwent contamination inspection prior to return to flight in September 2011 as well as more extensive post incident testing. This testing contributed to some of the overall F-22 contamination analysis. None of the ground incident aircraft cockpit testing revealed anything approaching a remarkable health guidance value. None of the maintainer blood, breath or urine samples indicated anything remarkable. Fluid found in the cockpit of one incident aircraft was evaluated and determined to be water with nothing remarkable. During one incident, investigators suspected tailwind engine exhaust may reach the cockpit and possibly effect maintainers. However, post incident testing and continued testing on two F-22 aircraft has indicated nothing remarkable. Engine run qualified ground maintenance personnel did receive updated engine run procedures to increase awareness, and to allow them to shutdown and reposition aircraft or equipment in the event of excessive exhaust. Engine run maintenance personnel also carried air sampling canisters in the cockpit for several months to capture any air samples from any potential incidents. However, no incidents occurred during this timeframe which was subsequent to the last ground incident in Dec 2011. Maintainers across the F-22 fleet perform in excess of a hundred engine runs every month-- runs which do not include aircraft movement. The Air Force has trained and implemented procedures for maintainers to quickly and safely shut down a running aircraft in the event of any future incidents. Additionally, appropriate aircraft and medical protocols are in place to respond to any future incidents. Mr. Bartlett. Please describe the Air Force's efforts to definitively determine that stealth coatings, along with other contaminants, did not cause any of these incidents. Could stealth coatings that were heated either on the ground or in flight cause contamination in that manner? General Lyon. LO Coatings and its breakdown products, along with other potential contaminants were incorporated into an extensive Molecular Characterization Matrix effort that thoroughly characterized, analyzed and documented over 900 compounds that could be present in aircraft environments. After several years of exhaustive testing both on the ground and in flight, no detected compounds levels have ever exceeded safe limits, or even been close to safe limit thresholds. All potential compound sources in an F-22 were evaluated including fuel, hydraulic fluid, engine oil, radar coolant, ambient air, engine exhaust, aircraft cleaning products, sealants, and coatings. Source breakdown analysis was performed and potential source information was incorporated into the Molecular Characterization Matrix for each compound. Of the 900 compounds characterized, only approximately 450 were ever detected on an F-22 aircraft. Compound detection methods used on F-22 aircraft were capable of detecting a full spectrum of compounds. Detection media included Thermal Desorption Tubes, SUMMA canisters, multi-RAEs, sock and swab analyses, Greywolf, PUF/XAD, Silica Gel, C2A1 filters and GRIMM/CPC particulate counter, among others. The detection methods used were capable of detecting a wide range of particulate matter, volatile and semi-volatile compounds, and standard gases. Over 2,000 total samples were taken using these devices, at different times, both on ground and in-flight. Chemists and toxicologists performed countless reviews of sampling techniques and methods and culminated their effort with a detection methods expert forum to ensure that the full spectrum of aircraft compounds would have been adequately detected by the methods used in testing and sample analysis. Post incident protocols were established as part of Return to Flight in September 2011 and completed after each incident flight and maintainer incident. The protocol directed sampling at various areas of the aircraft including cockpit and breathing line air. All incident aircraft had levels of detected compounds well below established safe limits. Safe limits were developed with a team of over 20 experienced toxicologists, doctors, and scientists from contractor, NASA, University, and USAF personnel. These limits were derived from established OSHA guidelines, existing available research, Permissible Exposure Limits (PELs), Short Term Exposure Limits (STELs), and other established guidelines for each compound. In addition to aircraft sampling, blood, urine, and exhaled breath samples were taken from all incident pilots and maintainers and reviewed by an independent medical team of 5 physiologists, toxicologists, and aerospace physicians from the contractor, USAF, University and NASA. No abnormalities were noted in any tests. If a pilot was exposed to reactive LO coating materials, pilot blood tests should have revealed abnormal levels of heavy metals present. None were detected. A thorough review of maintenance activities on incident aircraft was completed and there were no maintenance trends prior to incident flights. Incidents have not been linked to any specific maintenance activities, including initial LO application and/or coating repair. In addition, compounds unique to LO coatings are unlikely to still be present in their reactive state during flight operations, since precautions are taken when coatings are applied. The aircraft is isolated to prevent exposure to personnel and Technical Order Documents (TOD) dictate that the aircraft are not returned to flight line operations until coatings are cured and paints are dry. Therefore, it is highly unlikely that these coatings were present during ground or in-flight operations. Based on the exhaustive research conducted to date, the team believes that contamination is not the root cause of the F-22 Physiological Incidents. Mr. Bartlett. How do F-22 g-forces cause what is referred to as ``Raptor cough''? Why does the Air Force feel it is not related to the physiological incidents pilots are experiencing? General Lyon. The term ``Raptor Cough'' is commonly known as acceleration atelectasis. Acceleration atelectasis results from pilots breathing high concentrations of oxygen (above 60%) while wearing anti- G trousers, and exposure to G-forces. Atelectasis refers to the closure of alveoli in the terminal bronchioles as oxygen is absorbed into the blood stream, leaving no component of normal breathing gas (i.e. nitrogen) to keep them open. The normal physiologic response to re-open the alveoli is to cough. The F-22 consistently delivers higher concentrations of oxygen compared to legacy fighters increasing susceptibility to developing atelectasis. The Air Force feels that atelectasis may be a contributor to the ``Raptor Cough'' issue. The Air Force will continue to explore further potential causes through long term breathing air analysis and human systems integration efforts. Mr. Bartlett. What is the Air Force's level of confidence in whether or not the life support equipment issues are contributing to all of the physiological incidents with pilots and ground personnel in the F-22 community? General Lyon. The Root Cause Corrective Action (RCCA) team exhaustively investigated 414 separate fault tree branches to arrive at high confidence in the overall F-22 Life Support System equipment. The Upper Pressure Garment (UPG) valve is the only remaining vulnerability, and is on-track for resolution in December 2012. The F-22 LSS Task Force is very confident that we know what was causing physiological incidents. No single cause was identified; rather multiple factors defined during the root cause corrective action (RCCA) combine to produce symptoms. These factors include human factors, breathing system impedance, high O2 concentration, and Upper Pressure Garment restriction caused by a fill/dump valve that was not specifically designed for the F-22. Pilot/Maintainer variability contributes to symptom manifestation differences. We are also confident that factors other than the life support system or the aircraft caused the ground incidents. Mr. Bartlett. You have previously indicated that of the 11 reported ``cause unknown'' hypoxia events since return to fly in September 2011, less than half of those events are still unresolved. How many of the reported incidents can you contribute to an insufficient supply of oxygen? General Lyon. Of the 11 reported ``cause unknown'' events since September 2011, all 11 have been resolved under the general cause of restricted breathing. This determination was made through the independent investigations made at each mishap wing, supported by personnel and resources at the major command level along with experts from the F-22 program office, Lockheed-Martin, and outside support from experts at the U.S. Navy and NASA. Date Event Description20-Oct-11 Hypoxia symptoms on departure--restricted breathing 20-Oct-11 Post flight personnel recognized cognitive degradation from pilot--restricted breathing 31 Oct 11 Pilot experienced symptoms in flight--restricted breathing 15 Nov 11 Pilot experienced symptoms during high-G sortie--restricted breathing 14 Dec 11 Hypoxia symptoms in flight--restricted breathing 14 Feb 12 Confusion during/post flight--restricted breathing 17 Feb 12 Confusion during intercept trng--restricted breathing 17 Feb 12 Confusion during RTB--restricted breathing 23 Feb 12 Hypoxia symptoms during RTB--restricted breathing 1 Mar 12 Pilot confusion, Spatial D in IMC--restricted breathing 8 Mar 12 Hypoxia symptoms during night RTB--restricted breathing Mr. Bartlett. You have previously indicated that of the 11 reported ``cause unknown'' hypoxia events since return to fly in September 2011, less than half of those events are still unresolved. Could you provide an update on the status of each of those events including which are resolved with a cause for each, and which are still unresolved and actions being taken to address those unresolved cases? General Lyon. All of the events since September 2011 have been resolved under the general cause of restricted breathing. This determination was made through the independent investigations made at each mishap wing, supported by personnel and resources at the major command level along with experts from the F-22 program office, Lockheed-Martin, and outside support from experts at the U.S. Navy and NASA. Date Event Description20-Oct-11 Hypoxia symptoms on departure--restricted breathing 20-Oct-11 Post flight personnel recognized cognitive degradation from pilot--restricted breathing 31 Oct 11 Pilot experienced symptoms in flight--restricted breathing 15 Nov 11 Pilot experienced symptoms during high-G sortie--restricted breathing 14 Dec 11 Hypoxia symptoms in flight--restricted breathing 14 Feb 12 Confusion during/post flight--restricted breathing 17 Feb 12 Confusion during intercept trng--restricted breathing 17 Feb 12 Confusion during RTB--restricted breathing 23 Feb 12 Hypoxia symptoms during RTB--restricted breathing 1 Mar 12 Pilot confusion, Spatial D in IMC--restricted breathing 8 Mar 12 Hypoxia symptoms during night RTB--restricted breathing Mr. Bartlett. Were you provided access to any Air Force data or facilities your team deemed necessary to carry out your review of the Air Force's investigative process and root-cause analysis? Mr. Cragg. Yes, the USAF provided the NASA Engineering and Safety Center (NESC) F-22 Life Support System (LSS) Independent Analysis Team with access to all of the data and facilities needed. Mr. Bartlett. You mentioned in your written statement that you believed insufficient human-systems integration testing was accomplished before operational deployment of the F-22. What additional testing do you believe should have been accomplished? Mr. Cragg. One of the NESC's Team's recommendations was to ensure appropriate human system integration testing is performed before operational use of any new system or implementation of a change to an existing system. Life support components (e.g., the On-Board Oxygen Generator (OBOGs)) were all individually qualified and put into the system by a system integrator. The original F-22 qualification testing did not utilize the same Aircrew Flight Equipment (AFE) that is in use today. Many of the complex interactions between the end-to-end system and the pilots were just recently identified during the human centrifuge and altitude chamber testing. Mr. Bartlett. You noted in your written statement that in any jet fighter environment, irritant compounds like combustion exhaust gases, fuels, lubricants, and organic cleaning solvents can be present. Are you confident in the Air Force's analysis that irritant compounds could not be in the pilot's breathing air supply thereby causing hypoxia-like effects? Mr. Cragg. As stated, irritant compounds are present in any jet fighter environment, including the F-22. The NESC Team found no evidence of a contaminant producing a toxic exposure for the pilots flying the F-22. The NESC Team recommended that the USAF ``Consider a fundamental reassessment of requirements and assumptions for LSS in high performance aircraft.'' Such an assessment would provide a better understanding of the physiological effects of irritant compounds in high performance aircraft. Mr. Bartlett. What is the status of the NASA Engineering and Safety Center report, and when will it be released? Would you provide the committee a copy of the report when it is completed? Mr. Cragg. The USAF requested NASA's review of hypoxia-like issues with the F-22. On August 31, 2012, the NESC presented the USAF with the final report. Accordingly, the USAF is responsible for any further use or release of the report, and NASA has agreed to defer to the USAF on such requests. Mr. Bartlett. Are you confident that, in addition to removing the filter, improvements to the pilots' gear, such as the upper pressure garment, will fix the F-22's physiological problems? Mr. Cragg. The NESC Team believes that there are multiple issues affecting the pilot's physiology in the F-22. Addressing each of these issues will ensure that the hypoxia-like symptoms will become less likely. Removing the C2A1 filter that exacerbated the problems and fixing the Upper Pressure Garment are major improvements. ______ QUESTIONS SUBMITTED BY MR. RUNYAN Mr. Runyan. General Martin, in your testimony before the subcommittee, you stated that the decision to pull the backup oxygen system was made by a lower level team, not the chief engineer supervising the program. It was also stated that this was done to save weight and that assumptions were made that the main oxygen system would be improved to accommodate, however there was no coordination between the two teams and the main oxygen system did not receive any improvements to make up for the lack of a backup system. General Lyon and General Martin, please provide the full name(s) of each of the person(s) who made the decisions, what his/her/their current position is for each person who signed off, and what actions have been taken to hold these people accountable for their decisions in light of subsequent events. Thank you. General Martin. The decision to remove the F-22 Back-Up Oxygen capability was made at an F-22 Cockpit Requirements/Design Review Update on Wednesday, 15 Jan 92. ``B/U Oxygen--OBOGS'' was one of the 7 trade studies reviewed during this requirements/design review. The minutes of this review clearly show concurrence with the trade study recommendation to ``delete dedicated standby oxygen supply requirement for OBOGS backup'' and ``use emergency oxygen for emergencies.'' There were 25 government members at this meeting. After a thorough review of the Air Force's historical F-22 records, we are unable to determine who, specifically, made the decision to remove the F-22 Back-Up Oxygen capability from the F-22 design. Similarly, we have identified no instances in which adverse action was taken against an Air Force employee as a result of his/her making such a decision. Mr. Runyan. Do you think that you have found the actual cause of the problem? What is the source of the ``Raptor cough''? General Martin. The source of the ``Raptor Cough'' is a combination of breathing high concentrations of oxygen, wear of anti-G trousers, and exposure to G forces. Raptor Cough is commonly known as acceleration atelectasis. Acceleration atelectasis results from pilots breathing high concentrations of oxygen (above 60%) while wearing anti- G trousers, and exposure to G-forces. Atelectasis refers to the closure of alveoli in the terminal bronchioles as oxygen is absorbed into the blood stream, leaving no component of normal breathing gas (i.e. nitrogen) to keep them open. The normal physiologic response to re-open the alveoli is to cough. The F-22 consistently delivers higher concentrations of oxygen compared to legacy fighters increasing susceptibility to developing atelectasis. The Air Force feels that atelectasis may be a contributor to the ``Raptor Cough'' issue. The Air Force will continue to explore further potential causes through long term breathing air analysis and human systems integration efforts. Mr. Runyan. Can the F-22 be retrofitted with a current oxygen system that we can have full confidence in? General Martin. The Air Force has full confidence in the current F- 22 On-Board Oxygen Generation System based on our extensive testing during the F-22 Life Support System root cause investigation. Mr. Runyan. General Martin, in your testimony before the subcommittee, you stated that the decision to pull the backup oxygen system was made by a lower level team, not the chief engineer supervising the program. It was also stated that this was done to save weight and that assumptions were made that the main oxygen system would be improved to accommodate, however there was no coordination between the two teams and the main oxygen system did not receive any improvements to make up for the lack of a backup system. General Lyon and General Martin, please provide the full name(s) of each of the person(s) who made the decisions, what his/her/their current position is for each person who signed off, and what actions have been taken to hold these people accountable for their decisions in light of subsequent events. Thank you. General Lyon. The decision to remove the F-22 Back-Up Oxygen capability was made at an F-22 Cockpit Requirements/Design Review Update on Wednesday, 15 Jan 92. ``B/U Oxygen--OBOGS'' was one of the 7 trade studies reviewed during this requirements/design review. The minutes of this review clearly show concurrence with the trade study recommendation to ``delete dedicated standby oxygen supply requirement for OBOGS backup'' and ``use emergency oxygen for emergencies.'' There were 25 government members at this meeting. After a thorough review of the Air Force's historical F-22 records, we are unable to determine who, specifically, made the decision to remove the F-22 Back-Up Oxygen capability from the F-22 design. Similarly, we have identified no instances in which adverse action was taken against an Air Force employee as a result of his/her making such a decision. Mr. Runyan. Do you think that you have found the actual cause of the problem? What is the source of the ``Raptor cough''? General Lyon. The source of the ``Raptor Cough'' is a combination of breathing high concentrations of oxygen, wear of anti-G trousers, and exposure to G forces. Raptor Cough is commonly known as acceleration atelectasis. Acceleration atelectasis results from pilots breathing high concentrations of oxygen (above 60%) while wearing anti- G trousers, and exposure to G-forces. Atelectasis refers to the closure of alveoli in the terminal bronchioles as oxygen is absorbed into the blood stream, leaving no component of normal breathing gas (i.e. nitrogen) to keep them open. The normal physiologic response to re-open the alveoli is to cough. The F-22 consistently delivers higher concentrations of oxygen compared to legacy fighters increasing susceptibility to developing atelectasis. The Air Force feels that atelectasis may be a contributor to the ``Raptor Cough'' issue. The Air Force will continue to explore further potential causes through long term breathing air analysis and human systems integration efforts. Mr. Runyan. Can the F-22 be retrofitted with a current oxygen system that we can have full confidence in? General Lyon. The Air Force has full confidence in the current F-22 On-Board Oxygen Generation System based on our extensive testing during the F-22 Life Support System root cause investigation. Mr. Runyan. Why is the ACC commander, General Hostage, not at the hearing? Does he not consider this situation a serious problem? As a member of both the House Armed Services and House Veterans Affairs Committees, I would also like to have heard testimony directly from him since this all ultimately falls under his responsibility as ACC Commander. General Lyon. General Mike Hostage is happy to address any additional concerns of the committee anytime he is called. On this occasion, Maj Gen Lyon was called by the committee to appear on 13 September. As General Hostage's most senior staff officer and ACC's Director of Air and Space Operations, Maj Gen Lyon was appointed to lead the F-22 Life Support System (LSS) Task Force by the Secretary of the Air Force. This represented a major commitment of headquarters efforts. As LSS lead, Maj Gen Lyon was empowered to speak for the Air Force on the subject. He holds the seniority and position to speak authoritatively, and has the most comprehensive knowledge of the subject. General Hostage made F-22 pilot safety and operational capability a top priority for ACC through his orders, commitment of time and resources, and personal actions. Due to the seriousness of his concerns, General Hostage closely monitored the situation and made all the key decisions on this issue, such as approving the F-22s return to flying operations. Lastly, General Hostage took the step of becoming an F-22 pilot himself in order to gain firsthand knowledge of operating the aircraft, and to demonstrate his belief that the overall risk levels our pilots take while operating the F-22 is comparable with that associated with most other high performance aircraft, given the numerous corrective actions and operating guidelines now in place. Mr. Runyan. Do you think that you have found the actual cause of the problem? What is the source of the ``Raptor cough''? Mr. Cragg. The NESC Team believes that there are multiple issues affecting the pilot's physiology in the F-22. Addressing each of these issues will ensure that the hypoxia-like symptoms will become less likely. Removing the C2A1 filter that exacerbated the problems, adjusting the oxygen schedule down from ``Max,'' and fixing the Upper Pressure Garment are major improvements. The NESC Team believes that the ``Raptor Cough'' is likely caused by a combination of atelectasis, high oxygen concentrations, and other physiological factors. Mr. Runyan. Can the F-22 be retrofitted with a current oxygen system that we can have full confidence in? Mr. Cragg. The NESC Team believes that the current Honeywell On Board Oxygen Generator (OBOGs) is operating properly and as designed. ______ QUESTIONS SUBMITTED BY MS. SPEIER Ms. Speier. General Martin, you mentioned that the F-22 program's ability to detect these issues was degraded by the Air Force's increased reliance upon contractors. Do you know approximately what the ratio of government to contractor employees working on human systems integration was in the Air Force then, and what that ratio is now? General Martin. Thank you for the opportunity to clarify and expand on this issue. Although the Panel did not specifically review the ratio of government to contractor manning with regard to the human systems integration competencies, based on what the Panel members heard from contractor and USAF personnel with deep experience in the human system fields, the degradation in the ``detection of issues'' resulted from an overall reduction in government and contractor expertise in the field of human systems expertise within both the Air Force and the contractor community that occurred over a more than 20-year period beginning in 1990. In this context, ``human systems'' encompasses human factors engineering, human systems integration, aerospace physiology (research and operational), and aerospace life support systems design/ development/testing/evaluation. A significant reduction in manning and funding, for both the government and contractor workforces dealing with Human System Integration, Aviation Physiology, or Flight Medicine (especially in altitude physiology, altitude protection, oxygen generation systems, and occupational toxicology) occurred during the years of the F-22's engineering, development and manufacturing (EMD) phase and during its operational fielding. In Appendix E of the SAB's Aircraft Oxygen Generation Study Final Report, a discussion of that reduction is more fully described. Specifically, during the 1996-2000 period, Air Force Research Laboratory Human Effectiveness manpower (and the associated research funding) for continuing human effectiveness activities (including research and development of human systems integration, aviation physiology and flight medicine) was reduced by 44 percent. The Air Force indicated at the time it was willing to accept a higher risk in the application of human-centered technologies; and in particular, aircraft cockpit design technologies, environmental protection research, and life support systems were considered sufficiently mature that future research and development could therefore be accomplished by industry. While the Air Force can and does rely on contractor expertise in many fields that type of contractor-provided ``expert force in being'' exists only when funded over a period of time so that expertise can be developed and maintained at a high level. The contractor community does maintain certain (limited) ``core'' sets of technical expertise from within its own resources for vital future business reasons. However, the aerospace physiology and life support areas, especially as applicable to high performance military aircraft, represent a long term high commitment/low return area and in general, contractors have not maintained that technical expertise without significant continuing support (i.e., government funding/contracts for basic and applied research). Although in a slightly different context, the USAF faces much the same problem and, as mentioned above, has reduced its research capabilities and expertise accordingly. Ms. Speier. One of the findings of the Scientific Advisory Board was that the Air Force had insufficient capabilities and expertise for human systems integration. How does the Air Force plan to improve this expertise? General Lyon. The Air Force recognized the need to reestablish the Human Systems Integration competency in 2007 when we created the Air Force Human Systems Integration Office (AFHSIO) as a direct reporting agency to the Vice Chief of Staff of the Air Force. A recognition of the relationship of this office to weapon systems development resulted in a realignment of this office to the Undersecretary of the Air Force for Acquisition in 2009. The AFHSIO serves as a central policy source and tracking center for human systems integration (HSI) in acquisition programs. The team is currently assessing the number of HSI practitioners required, developing a concept of operations (CONOPS) for supporting program offices, determining training and certification required, and establishing a reporting mechanism. Ms. Speier. General Lyon, the Safety Advisory Board recommended more clearly defining inherently governmental roles and responsibilities in the Air Force's acquisition processes and core competencies. How has the Air Force responded to this recommendation? General Lyon. The Office of the Deputy Assistant Secretary of the Air Force for Acquisition Integration (SAF/AQX) reviewed, updated, published guidance, and reported the results of their review to the Military Deputy, Office of the Secretary of the Air Force for Acquisition (SAF/AQ). Ms. Speier. Mr. Cragg, you said that your team's conclusions ``do not represent an exhaustive review of all F-22 documentation.'' What other documentation would an exhaustive review include? Mr. Cragg. The NESC Team would define ``exhaustive review'' to include review and evaluation of every single document and data source. An exhaustive review requires a significant amount of time and personnel. Based on the NESC Team's experience, the key documents necessary to understand the situation and to provide significant recommendations to the USAF were identified and reviewed. Ms. Speier. Mr. Cragg, what issues should the Air Force explore in any studies of the long term impacts of the F-22's physiological strain? Mr. Cragg. The NESC Team believes that in some cases there could be a hypoxic-ischemic injury to certain areas of the brain that accounts for the prolonged neurocognitive symptoms experienced by some pilots. Based on early discussions with USAF medical representatives, a more objective assessment of neurocognitive function (e.g. computerized testing), as well as certain imaging studies (e.g. MRI of the brain), may be warranted in pilots who experience prolonged hypoxia-like symptoms associated with F-22 flight. Pulmonary function and diffusion testing for all F-22 pilots should also be considered. Further specifics of such testing (e.g. type and frequency) would best be addressed by technical experts in this field. ______ QUESTIONS SUBMITTED BY MR. LOEBSACK Mr. Loebsack. What solutions has the Air Force reviewed to solve the hypoxia problems experienced by pilots? Specifically, what oxygen delivery system changes have been reviewed and were all available solutions reviewed? General Martin. The Air Force has reviewed various proposed solutions to the hypoxia problems experienced by pilots. Included are modifications to the breathing assembly such as the Raptor 2 modification which introduced a chemical warfare canister in-line with air supply to the pilot. This was done to mitigate potential contamination before this theory was disproven. Further, the Air Force required pilots to wear pulse oximeters for the first time in history in an attempt to quantify arterial blood saturation. We have reviewed numerous other potential solutions including modifications to the aircraft and have concluded that adding an automatic back-up oxygen system would meet requirements to have immediate 100% oxygen available in the event of a rapid decompression at extreme high altitudes. Other potential solutions investigated included changing the oxygen source from the current on board system to liquid and/or gaseous oxygen systems. Mr. Loebsack. Since the Air Force pointed to the recent travel of F-22s to Japan as an indicator that the hypoxia problem has been solved, does that mean that there were no risk mitigation restrictions placed on the F-22s during the transit? General Martin. The Air Force has kept all risk mitigation measures in place during F-22 long duration flights. Since resuming long- distance F-22 missions in February 2012, the Air Force has completed over 100 long-distance F-22 sorties, totaling over 650 hours. There have been zero conditions or physiological incidents during any of these sorties that would require the use of these risk mitigation measures. After thorough investigation there is no data to suggest that these risk mitigations are any more necessary on long-duration F-22 movements than with any other USAF fighter aircraft. Mr. Loebsack. What solutions has the Air Force reviewed to solve the hypoxia problems experienced by pilots? Specifically, what oxygen delivery system changes have been reviewed and were all available solutions reviewed? General Lyon. The Air Force has reviewed various proposed solutions to the hypoxia problems experienced by pilots. Included are modifications to the breathing assembly such as the Raptor 2 modification which introduced a chemical warfare canister in-line with air supply to the pilot. This was done to mitigate potential contamination before this theory was disproven. Further, the Air Force required pilots to wear pulse oximeters for the first time in history in an attempt to quantify arterial blood saturation. Mr. Loebsack. Since the Air Force pointed to the recent travel of F-22s to Japan as an indicator that the hypoxia problem has been solved, does that mean that there were no risk mitigation restrictions placed on the F-22s during the transit? General Lyon. The Air Force has kept all risk mitigation measures in place during F-22 long duration flights. Since resuming long- distance F-22 missions in February 2012, the Air Force has completed over 100 long-distance F-22 sorties, totaling over 650 hours. There have been zero conditions or physiological incidents during any of these sorties that would require the use of these risk mitigation measures. After thorough investigation there is no data to suggest that these risk mitigations are any more necessary on long-duration F-22 movements than with any other USAF fighter aircraft.