[Federal Register Volume 66, Number 185 (Monday, September 24, 2001)]
[Rules and Regulations]
[Pages 48791-48792]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-23730]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NE-41-AD; Amendment 39-12442; AD 2001-19-03]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (Formerly 
Allison Engine Company) Model AE 3007A and AE 3007C Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), that 
is applicable to Rolls-Royce Corporation (formerly Allison Engine 
Company) Model AE 3007A and AE 3007C turbofan engines with a certain 
part number high pressure turbine (HPT) 1st to 2nd stage turbine spacer 
installed. This amendment requires removal and replacement of that HPT 
1st to 2nd stage turbine spacer before it reaches its new reduced 
engine cycle life limit.This amendment is prompted by the results of a 
detailed component analysis that indicates that the HPT 1st to 2nd 
stage turbine spacer stresses are higher than predicted.The actions 
specified by this AD are intended to prevent HPT 1st to 2nd stage 
turbine spacer failure which could result in an uncontained engine 
failure and damage to the airplane.

DATES: Effective date October 29, 2001.

FOR FURTHER INFORMATION CONTACT: Michael Downs, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 
2300 E. Devon Ave., Des Plaines, IL 60018; telephone (847) 294-7870, 
fax (847) 294-7834.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an AD that is 
applicable to Rolls-Royce Corporation (formerly Allison Engine Company) 
Model AE 3007A and AE 3007C turbofan engines with HPT 1st to 2nd stage 
turbine spacer part number (P/N) 23058369 installed was published in 
the Federal Register on February 22, 2001 (66 FR 11126). That action 
proposed to require removal and replacement of the HPT 1st to 2nd stage 
turbine spacer P/N 23058369 before it reaches its new reduced engine 
cycle life limit.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposal or the FAA's determination of the cost to the public. The FAA 
has determined that air safety and the public interest require the 
adoption of the rule as proposed.

Economic Impact

    There are approximately 378 engines of the affected design in the 
worldwide fleet. The FAA estimates that 300 engines installed on 150 
airplanes of U.S. registry would be affected by this proposed AD. It 
will take approximately 13 work hours per engine to accomplish the 
removal and replacement of the affected HPT 1st to 2nd stage spacer. 
The 13 work hours cited include teardown and reassembly from the module 
level, but not engine removal. Engines are rarely scheduled off-wing 
solely for the purpose of replacement of time-expired components.The 
average labor rate is $60 per work hour. Required parts will cost 
approximately $10,012 per engine. Based on these figures, the FAA 
estimates the total cost impact of the proposed AD on U.S. operators, 
to be $3,237,600. Because most of the fleet field parts are below the 
new value, special scheduling should not be required.

Regulatory Impact

    This final rule does not have federalism implications, as defined 
in Executive Order 13132, because it would 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. Accordingly, 
the FAA has not consulted with state authorities prior to publication 
of this final rule.
    For the reasons discussed above, I certify that this action (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 final evaluation has been prepared for 
this action and it 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.

Adoption of the Amendment

    Accordingly, pursuant to 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

    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 adding a new airworthiness directive to 
read as follows:

2001-19-03  Rolls-Royce Corporation (formerly Allison Engine 
Company) Model AE 3007A and AE 3007C turbofan engines with high 
pressure turbine (HPT) 1st to 2nd stage turbine spacer part number 
(P/N) 23058369 installed.

[[Page 48792]]

Amendment 39-12442. Docket 2000-NE-41-AD.

Applicability

    This airworthiness directive (AD) is applicable to Rolls-Royce 
Corporation (formerly Allison Engine Company) Model AE 3007A and AE 
3007C turbofan engines with HPT 1st to 2nd stage turbine spacer P/N 
23058369 installed. These engines are installed on, but not limited 
to Empresa Brasileira de Aeronautica S.A. (EMBRAER) EMB-145, and 
Cessna 750 series airplanes.

    Note 1: This AD applies to each engine 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 engines 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

    Compliance with this AD is required as indicated, unless already 
done.
    To prevent HPT 1st to 2nd stage turbine spacer failure, which 
could result in an uncontained engine failure and damage to the 
airplane, do the following:

New Reduced Engine Cycle Life Limit

    (a) For all Rolls-Royce Corporation Model AE 3007A and AE 3007C 
turbofan engines with HPT 1st to 2nd stage turbine spacer, P/N 
23058369 installed, remove spacer before reaching the new reduced 
engine cycle life limit of 9,400 cycles and replace with a 
serviceable part.
    (b) Revise the airworthiness limitations section of the 
Instruction for Continued Airworthiness, as follows: P/N 
23058369=9,400 cycles.

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, Chicago Aircraft Certification 
Office. Operators must submit their request through an appropriate 
FAA Principal Maintenance Inspector, who may add comments and then 
send it to the Manager, Chicago Aircraft Certification Office (ACO).

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Chicago 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 aircraft to a location where 
the requirements of this AD can be accomplished.
    (e) This amendment becomes effective on October 29, 2001.

    Issued in Burlington, Massachusetts, on September 17, 2001.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.

[FR Doc. 01-23730 Filed 9-21-01; 8:45 am]
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