[Federal Register Volume 76, Number 193 (Wednesday, October 5, 2011)]
[Rules and Regulations]
[Pages 61559-61561]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-25654]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0392; Directorate Identifier 2011-NE-12-AD;
Amendment 39-16808; AD 2011-19-03]
RIN 2120-AA64
Airworthiness Directives; General Electric Company (GE) CT7-8,
CT7-8A, CT7-8A1, CT7-8E, and CT7-8F5 Turboshaft Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for the
products listed above. This AD was prompted by four reports of
unrecoverable engine stalls, during hover in a left-roll attitude. This
AD requires the installation of an accessory gearbox (AGB) axis-A oil
slinger nut to the axis-A shaft assembly. We are issuing this AD to
prevent an unrecoverable engine stall, leading to a helicopter forced
landing or accident.
DATES: This AD is effective November 9, 2011.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of November 9,
2011.
ADDRESSES: For service information identified in this AD, contact GE-
Aviation, M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215; phone:
513-552-3272; e-mail: [email protected]. You may review copies of the
referenced service information at the FAA, Engine & Propeller
Directorate, 12 New England Executive Park, Burlington, MA. For
information on the availability of this material at the FAA, call 781-
238-7125.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (phone: 800-647-5527) is Document Management Facility,
U.S. Department of Transportation, Docket Operations, M-30, West
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Walter Meibaum, Aerospace Engineer,
[[Page 61560]]
Engine & Propeller Directorate, FAA, 12 New England Executive Park,
Burlington, MA 01803; phone: 781-238-7119; fax: 781-238-7199; e-mail:
[email protected].
SUPPLEMENTARY INFORMATION:
Discussion
We received four reports of GE CT7-8 series turboshaft helicopter
engines experiencing unrecoverable engine stalls, during hover in a
left-roll attitude. Investigation revealed that during a prolonged left
roll, excessive return oil from the AGB may return to the A-sump and
exceed the sump's scavenging capability. The sump then floods, leading
to over-heated oil, which preheats the air entering the engine's
compressor. This preheated air causes inlet thermal distortion. This
condition, if not corrected, could result in an unrecoverable engine
stall, leading to a helicopter forced landing or accident. We issued a
notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include
an AD that would apply to the specified products. That NPRM published
in the Federal Register on May 2, 2011 (76 FR 24407). That NPRM
proposed to require the installation of an AGB axis-A oil slinger nut
to the axis-A shaft assembly.
Comments
We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM published in the Federal
Register on May 2, 2011 (76 FR 24407).
Since we issued the NPRM published in the Federal Register on May
2, 2011 (76 FR 24407), GE issued a revision to the service bulletin we
are incorporating by reference in this AD. The revision includes new
information in the procedure required to torque the oil slinger nut.
This AD incorporates by reference, GE Aircraft Engines CT7-8 Turboshaft
Engine Service Bulletin No. CT7-8 S/B 72-0033, Revision 1, dated April
28, 2011.
Also since we issued the NPRM published in the Federal Register on
May 2, 2011 (76 FR 24407), we discovered that in the applicability
paragraph, we inadvertently omitted engine serial number 953071. We
corrected that omission in paragraph (c) (4) by changing ``CT7-8E,
engine S/Ns 953068 and below, and S/Ns 953070 and 953072'' to ``CT7-8E,
engine S/Ns 953068 and below, and S/Ns 953070 through 953072''.
Conclusion
We reviewed the relevant data and determined that air safety and
the public interest require adopting the AD as proposed except for
minor editorial changes. We have determined that these minor changes
are consistent with the intent that was proposed in the NPRM published
in the Federal Register on May 2, 2011 (76 FR 24407) for correcting the
unsafe condition.
Costs of Compliance
We estimate that this AD will affect 80 engines installed on
helicopters of U.S. registry. We also estimate that it will take about
one work-hour per engine to perform the actions required by this AD,
and that the average labor rate is $85 per work-hour. Required parts
will cost about $700 per engine. Based on these figures, we estimate
the total cost of the AD to U.S. operators to be $62,800.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, part A, subpart III, Section 44701: ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
Regulatory Findings
This AD will not have federalism implications under Executive Order
13132. This AD will not have a substantial direct effect 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.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2011-19-03 General Electric Company: Amendment 39-16808; Docket No.
FAA-2011-0392; Directorate Identifier 2011-NE-12-AD.
Effective Date
(a) This AD is effective November 9, 2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to the following General Electric Company
(GE) turboshaft engines:
(1) CT7-8, all engine serial numbers (S/Ns).
(2) CT7-8A, engine S/Ns 947565 and below.
(3) CT7-8A1, engine S/Ns 530017 and below.
(4) CT7-8E, engine S/Ns 953068 and below, and S/Ns 953070
through 953072.
(5) CT7-8F5, engine S/Ns 731005 and below, and S/Ns 731007,
731008, 817021, and 817022.
Unsafe Condition
(d) This AD was prompted by four reports of unrecoverable engine
stalls, during hover in a left-roll attitude. We are issuing this AD
to prevent an unrecoverable engine stall, leading to a helicopter
forced landing or accident.
Compliance
(e) Comply with this AD at the next engine shop visit, the next
1,500-hour helicopter inspection, or before operation after next
engine installation, whichever occurs first.
Installation of Accessory Gearbox (AGB) Axis-A Oil Slinger Nut
(f) Install the AGB axis-A oil slinger nut to the axis-A shaft
assembly. Use Accomplishment Instructions, paragraphs 3.A. through
3.C. of GE Aircraft Engines CT7-8 Turboshaft Engine Service Bulletin
No. CT7-8 S/B 72-0033, Revision 1, dated April 28, 2011, to do the
installation.
[[Page 61561]]
Previous Credit
(g) An oil slinger nut installation performed before the
effective date of this AD using GE Aircraft Engines CT7-8 Turboshaft
Engine Service Bulletin No. CT7-8 S/B 72-0033, dated February 11,
2011, satisfies the installation requirements of this AD.
Alternative Methods of Compliance (AMOCs)
(h) The Manager, Engine Certification Office, FAA, has the
authority to approve AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19.
Related Information
(i) For more information about this AD, contact Walter Meibaum,
Aerospace Engineer, Engine & Propeller Directorate, FAA, 12 New
England Executive Park, Burlington, MA 01803; phone: 781-238-7119;
fax: 781-238-7199; e-mail: [email protected].
Material Incorporated by Reference
(j) You must use the following service information to do the
actions required by this AD, unless the AD specifies otherwise. The
Director of the Federal Register approved the incorporation by
reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the
following service information on the date specified:
(1) GE Aircraft Engines CT7-8 Turboshaft Engine Service Bulletin
No. CT7-8 S/B 72-0033, Revision 1, dated April 28, 2011, approved
for IBR November 9, 2011.
(2) For service information identified in this AD, contact GE-
Aviation, M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215; phone:
513-552-3272; e-mail: [email protected].
(3) You may review copies of the service information at the FAA,
Engine & Propeller Directorate, 12 New England Executive Park,
Burlington, MA. For information on the availability of this material
at the FAA, call 781-238-7125.
(4) You may also review copies of the service information that
is incorporated by reference at the National Archives and Records
Administration (NARA). For information on the availability of this
material at an NARA facility, call 202-741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
Issued in Burlington, Massachusetts, on September 8, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 2011-25654 Filed 10-4-11; 8:45 am]
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