Airworthiness Directives; General Electric Company Aircraft Engines (GEAE) CT7-8A Turboshaft Engines

[Federal Register Volume 71, Number 73 (Monday, April 17, 2006)]
[Rules and Regulations]
[Pages 19627-19628]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-3616]



[[Page 19627]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24261; Directorate Identifier 2006-NE-12-AD; 
Amendment 39-14566; AD 2006-06-51]
RIN 2120-AA64


Airworthiness Directives; General Electric Company Aircraft 
Engines (GEAE) CT7-8A Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting emergency airworthiness directive (EAD) 2006-06-51 that we 
sent previously to all known U.S. owners and operators of GEAE CT7-8A 
turboshaft engines installed on Sikorsky S92 helicopters. This AD 
requires initial and repetitive inspections of the electrical chip 
detectors for the No. 3 bearing. This AD results from two failures of 
the No. 3 bearing in GEAE CT7-8A engines. We are issuing this AD to 
prevent failures of the No. 3 bearings and possible dual in-flight 
shutdowns of the engines.

DATES: This AD becomes effective May 2, 2006 to all persons except 
those persons to whom it was made immediately effective by emergency AD 
2006-06-51, issued on March 17, 2006, which contained the requirements 
of this amendment.
    We must receive any comments on this AD by June 16, 2006.

ADDRESSES: Use one of the following addresses to comment on this AD.
    <bullet> DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
    <bullet> Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
    <bullet> Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
    <bullet> Fax: (202) 493-2251.
    <bullet> Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Mark Bouyer, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803, telephone (781) 238-
7755; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: On March 17, 2006, the FAA issued emergency 
AD 2006-06-51, that applies to certain serial number GEAE CT7-8A 
turboshaft engines installed on Sikorsky S92 helicopters. That AD 
requires an initial inspection of the electrical chip detector for 
debris within 25 hours time-in-service after the effective date of that 
EAD, and thereafter, repetitive inspections within 25 hours time-since-
last inspection. That AD resulted from reports of two failures of the 
No. 3 bearings on GEAE CT7-8A turboshaft engines. Bearing contamination 
by Aluminum Oxide caused the first failure. The Aluminum Oxide 
contamination is a hard-particle contamination, left in the air cavity 
of the front frame core after cleaning, that entered the bearing and 
caused damage and metal loss at the roller ball and race interface. The 
loss of metal caused a warning light for an electrical chip detector to 
illuminate in the cockpit. The pilot reduced power to the engine. 
Inspection found the bearing unserviceable. The engine accumulated 458 
flight hours-since-new before the failure. Improper use of a bearing 
support tool at production assembly caused the second failure. Damage 
from improper use of a bearing support tool caused bearing metal loss 
at the roller ball and race interface. The loss of metal caused a 
warning light for an electrical chip detector to illuminate in the 
cockpit and signaled an impending oil bypass. The pilot performed an 
in-flight shutdown of the engine. The engine accumulated 686 hours-
since-new. This condition, if not corrected, could result in failures 
of the No. 3 bearings and possible dual in-flight shutdowns of the 
engines.

FAA's Determination and Requirements of This AD

    Since the unsafe condition described is likely to exist or develop 
on other engines of the same type design, we issued emergency AD 2006-
06-51 to prevent failures of the No. 3 bearings and possible dual in-
flight shutdowns of the engines. This AD requires:
    <bullet> Within 25 hours time-in-service after the effective date 
of this AD, inspecting the electrical chip detector assembly.
    <bullet> Staggering the inspection intervals so the chip detectors 
on both engines on the same helicopter are not inspected at the same 
time.
    <bullet> Thereafter, within 25 hours time-since-last inspection, 
performing a repetitive inspection, and
    <bullet> If the chip detector assembly contains any bearing 
material, replacing the engine.

FAA's Determination of the Effective Date

    Since an unsafe condition exists that requires the immediate 
adoption of this AD, we have found that notice and opportunity for 
public comment before issuing this AD are impracticable. We found that 
good cause existed to make the AD effective immediately on March 17, 
2006, to all known U.S. owners and operators of certain SN GEAE CT7-8A 
turboshaft engines installed on Sikorsky S92 helicopters. These 
conditions still exist, and we are publishing the AD in the Federal 
Register as an amendment to Section 39.13 of part 39 of the Code 
Federal Regulations (14 CFR part 39) to make it effective to all 
persons.

Interim Action

    These actions are interim actions and we may take further 
rulemaking actions in the future.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment. However, we invite you to send us any written relevant data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. FAA-2006-24261; 
Directorate Identifier 2006-NE-12-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify it.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this AD. Using the search function of the DMS Web 
site, anyone can find and read the comments in any of our dockets, 
including the name of the individual who sent the comment (or signed 
the comment on behalf of an association, business, labor union, etc.).

Examining the AD Docket

    You may examine the docket that contains the AD, any comments 
received, and any final disposition in person at the Docket Management 
Facility Offices between 9 a.m. and 5

[[Page 19628]]

p.m., Monday through Friday, except Federal holidays. The Docket Office 
(telephone (800) 647-5227) is located on the plaza level of the 
Department of Transportation Nassif Building at the street address 
stated in ADDRESSES. Comments will be available in the AD docket 
shortly after receipt.

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

    We have determined that 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 the 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. 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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
Under the authority delegated to me by the Administrator, the Federal 
Aviation Administration amends part 39 of the Federal Aviation 
Regulations (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:

2006-06-51 General Electric Company Aircraft Engines: Amendment 39-
14566. Docket No. FAA-2006-24261; Directorate Identifier 2006-NE-12-
AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective May 2, 
2006, to all persons except those persons to whom it was made 
immediately effective by emergency AD 2006-06-51, issued March 17, 
2006, which contained the requirements of this amendment.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to General Electric Company Aircraft Engines 
(GEAE) CT7-8A serial numbers (SNs) 947201 through 947204, 947209 
through 947235, 947238 through 9472268, 947273 through 947281, and 
947283 though 947285. These engines are installed on, but not 
limited to, Sikorsky S92 helicopters.

Unsafe Condition

    (d) This AD results from two failures of the No. 3 bearing in 
GEAE CT7-8A engines. We are issuing this AD to prevent failures of 
the No. 3 bearings and possible dual in-flight shutdowns of the 
engines.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Initial Inspection of the Electrical Chip Detector

    (f) Within 25 hours time-in-service after the effective date of 
this AD, do the following:
    (1) Remove the electrical chip detector assembly.
    (2) If the chip detector assembly contains any bearing material, 
replace the engine.
    (3) Stagger the inspection intervals so the chip detectors on 
both engines on the same helicopter are not inspected at the same 
time.

Repetitive Inspection of the Electrical Chip Detector

    (g) Thereafter, within 25 hours time-since-last inspection, 
perform the inspection specified in paragraph (f)(1) through (f)(3) 
of this AD.

Alternative Methods of Compliance

    (h) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (i) None.


    Issued in Burlington, Massachusetts, on April 11, 2006.
Francis A. Favara,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 06-3616 Filed 4-14-06; 8:45 am]
BILLING CODE 4910-13-P

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