[Federal Register Volume 64, Number 78 (Friday, April 23, 1999)] [Proposed Rules] [Pages 19938-19940] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-10185] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 98-NM-371-AD] RIN 2120-AA64 Airworthiness Directives; Lockheed Model 382 Series Airplanes AGENCY: Federal Aviation Administration, DOT. ACTION: Notice of proposed rulemaking (NPRM). ----------------------------------------------------------------------- SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Lockheed Model 382 series airplanes. This proposal would require a one-time visual inspection of the under floor to ring fittings at fuselage station 817E to verify installation of the correct sized fasteners; and follow-on corrective actions, if necessary. This proposal is prompted by notification from the manufacturer indicating that during production incorrect sized fasteners were installed on the under floor to ring fittings at fuselage station 817E. The actions specified by the proposed AD are intended to prevent fatigue cracking of the fastener holes and adjacent fuselage structure due to installation of the incorrect sized fasteners, which could result in reduced structural integrity of the airplane. DATES: Comments must be received by June 7, 1999. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-371-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. The service information referenced in the proposed rule may be obtained from Lockheed Martin Aeronautical Systems Support Company (LMASSC), Field Support Department, Dept. 693, Zone [[Page 19939]] 0755, 2251 Lake Park Drive, Smyrna, Georgia 30063. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia. FOR FURTHER INFORMATION CONTACT: Thomas Peters, Aerospace Engineer, Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone (770) 703-6063; fax (770) 703-6097. SUPPLEMENTARY INFORMATION: Comments Invited Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 98-NM-371-AD.'' The postcard will be date stamped and returned to the commenter. Availability of NPRMs Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-371-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Discussion The FAA has received notification from the manufacturer indicating that during production, incorrect sized fasteners were installed on Lockheed Martin Model 382 series airplanes. These fasteners are located on the under floor to ring fittings (aft ``pork chop'' fittings) at fuselage station 817E. The installation of \5/32\-inch diameter fasteners in lieu of the correct \3/16\-inch diameter fasteners could cause fatigue cracking of the fuselage structure by increasing the stress loads of the fuselage skin. Such cracking, if not detected and corrected, could result in reduced structural integrity of the airplane. Explanation of Relevant Service Information The FAA has reviewed and approved Lockheed Hercules Alert Service Bulletin A382-53-57, Revision 1, dated January 30, 1997, which describes procedures for a one-time visual inspection of the under floor to ring fittings (aft ``pork chop'' fittings) at fuselage station 817E to verify installation of the correct sized fasteners; and follow- on corrective actions, if necessary. The follow-on corrective actions involve measurement of the distance between the incorrect sized fasteners, removal of discrepant fasteners, and a visual inspection of the fastener holes and surrounding areas to detect discrepancies (damage, corrosion, or misdrilled or elongated fastener holes). The alert service bulletin also describes procedures for redrilling the fastener holes at fuselage station 817E, visually inspecting the fastener holes to confirm damage removal, and installing new fasteners. Accomplishment of the actions specified in the alert service bulletin is intended to adequately address the identified unsafe condition. Explanation of Requirements of Proposed Rule Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the alert service bulletin described previously, except as discussed below. Differences Between Proposed Rule and Service Bulletin Operators should note that the alert service bulletin specifies that visual inspection and/or rework of the under floor to ring fasteners at fuselage station 817E be accomplished upon receipt of the alert service bulletin, or an immediate cabin pressurization limit of 8.75 in Hg (4.3 psi) is to be implemented. However, the FAA finds that a 30-day compliance time for accomplishment of the inspection and rework is adequate in that the FAA has determined that fatigue cracking originating at the fastener holes caused by the installation of incorrect size of fasteners could result in loss of pressurization, but not an ``explosive decompression'' or severe structural degradation. In light of this, the FAA finds that it is not necessary to implement an immediate cabin pressurization limit of 8.75 in Hg (4.3 psi) for affected airplanes to continue to operate without compromising safety. Operators also should note that, although the alert service bulletin specifies that the manufacturer may be contacted for disposition of certain repair conditions, this proposal would require the repair of those conditions to be accomplished in accordance with a method approved by the FAA. Cost Impact There are approximately 112 airplanes of the affected design in the worldwide fleet. The FAA estimates that 18 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hour per airplane to accomplish the proposed inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the inspection proposed by this AD on U.S. operators is estimated to be $1,080, or $60 per airplane. The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. Regulatory Impact The regulations proposed herein would not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft [[Page 19940]] regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Safety. The Proposed Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: PART 39--AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. Sec. 39.13 [Amended] 2. Section 39.13 is amended by adding the following new airworthiness directive: Lockheed: Docket 98-NM-371-AD. Applicability: Model 382 series airplanes as listed in paragraph 1.A.(1) (``Effectivity'') of Lockheed Hercules Alert Service Bulletin A382-53-57, Revision 1, dated January 30, 1997; certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Compliance: Required as indicated, unless accomplished previously. To prevent fatigue cracking of the fastener holes and adjacent fuselage structure due to installation of the incorrect sized fasteners, which could result in reduced structural integrity of the airplane, accomplish the following: (a) Within 30 days after the effective date of this AD, perform a one-time visual inspection of the under floor to ring fittings at fuselage station 817E to verify installation of the correct sized fasteners, in accordance with Lockheed Hercules Alert Service Bulletin A382-53-57, Revision 1, dated January 30, 1997. Note 2: Inspections, repairs, or replacements that have been accomplished prior to the effective date of this AD, in accordance with Lockheed Hercules Alert Service Bulletin A382-53-57, dated January 16, 1997, are considered acceptable for compliance with the applicable action specified by this AD. (1) If all fasteners are the correct size, no further action is required by this AD. (2) If any fastener is determined to be the incorrect size, prior to further flight, measure the distance between the fastener centers in accordance with the alert service bulletin. (i) If the distance between the fastener centers is less than 0.57 inch, prior to further flight, repair in accordance with a method approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate. (ii) If the distance between the fastener centers is greater than or equal to 0.57 inch, prior to further flight, accomplish the requirements of paragraph (b) of this AD. (b) For all airplanes on which the distance between the fastener centers is greater than or equal to 0.57 inch: Prior to further flight, remove any incorrect sized fastener and perform a one-time visual inspection of the fastener holes and adjacent fuselage structure to detect discrepancies (damage, corrosion, or misdrilled or elongated fastener holes) in accordance Lockheed Hercules Alert Service Bulletin A382-53-57, Revision 1, January 30, 1997. (1) If no discrepancy is detected, prior to further flight, redrill the fastener holes to the correct size and install correct sized fasteners in accordance with the alert service bulletin. (2) If any discrepancy is detected, prior to further flight, redrill the fastener holes to the correct size and perform an additional one-time visual inspection of the redrilled holes to detect remaining discrepancies (damage, corrosion, or misdrilled or elongated fastener holes) of the affected area, in accordance with the alert service bulletin. (i) If no remaining discrepancy is detected, prior to further flight, install the correct sized fasteners in accordance with the alert service bulletin. (ii) If any remaining discrepancy is detected, prior to further flight, repair in accordance with a method approved by the Manager, Atlanta ACO. Alternative Methods of Compliance (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO. Special Flight Permits (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Issued in Renton, Washington, on April 19, 1999. D. L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-10185 Filed 4-22-99; 8:45 am] BILLING CODE 4910-13-U