AD 2001-25-05

[Federal Register Volume 66, Number 244 (Wednesday, December 19, 2001)]
[Rules and Regulations]
[Pages 65427-65429]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-30952]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-46-AD; Amendment 39-12558; AD 2001-25-05]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (Formerly 
Allison Engine Company) AE 3007 Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), that is applicable to Rolls-Royce Corporation (formerly Allison 
Engine Company) AE 3007 series turbofan engines. That AD currently 
requires removal of certain compressor cone shafts from service before 
exceeding new cyclic life limits and replacement with serviceable 
parts. This amendment requires increasing the cyclic life limit for 
certain serial numbers of new compressor cone shafts, part number (P/N) 
23070729, that are used on AE3007A1/3 and AE3007A1P engines. This 
amendment is prompted by recent approved changes in engineering and 
manufacturing processes for new compressor cone shafts P/N 23070729. 
The actions specified by this AD are intended to prevent low-cycle 
fatigue (LCF) failure of cone shafts, which could result in an 
uncontained engine failure and damage to the airplane.

DATES: Effective date January 23, 2002.

ADDRESSES: The information in this AD may be examined, by appointment, 
at the Federal Aviation Administration (FAA), New England Region, 
Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Michael Downs, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 
2300 East Devon Avenue, 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) by superseding AD 2000-09-05, 
Amendment 39-11714 (65 FR 26121, May 5, 2000), which is applicable to 
Rolls-Royce Corporation (formerly Allison Engine Company) AE 3007 
series turbofan engines was published

[[Page 65428]]

in the Federal Register on May 25, 2001 (66 FR 28850). That action 
proposed to require increasing the cyclic life limit for certain serial 
numbers of new compressor cone shafts, part number (P/N) 23070729, that 
are used on AE3007A1/3 and AE3007A1P engines.

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 Analysis

    There are approximately 598 Rolls-Royce Corporation (formerly 
Allison Engine Company) AE 3007 series turbofan engines of the affected 
design in the worldwide fleet. The FAA estimates that 364 engines 
installed on airplanes of U.S. registry will be affected by this AD, 
that it will take approximately 150 work hours per engine to accomplish 
the required actions, and that the average labor rate is $60 per work 
hour. Required parts will cost approximately $3,921 per engine. Based 
on these figures, the total cost impact of the AD on U.S. operators is 
estimated to be $4,703,244.

Regulatory Analysis

    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 by removing Amendment 39-11714 (65 FR 
26121, May 5, 2000) and by adding a new airworthiness directive, 
Amendment 39-12558, to read as follows:

2001-25-05  Rolls-Royce Corporation: Amendment 39-12558. Docket No. 
99-NE-46-AD. Supersedes AD 2000-09-05, Amendment 39-11714.

Applicability

    This airworthiness directive (AD) is applicable to Rolls-Royce 
Corporation (formerly Allison Engine Company) models AE 3007A, AE 
3007A1, AE 3007A1/1, AE 3007A1/2, AE 3007A1/3, AE 3007A1P, and AE 
3007C turbofan engines, with compressor cone shafts, part numbers 
(P/N's) 23050728 and 23070729, installed. These engines are 
installed on but not limited to EMBRAER EMB-135 and EMB-145 series 
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 (h) 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 low-cycle fatigue (LCF) failure of cone shafts, which 
could result in an uncontained engine failure and damage to the 
airplane, do the following:
    (a) For Rolls-Royce Corporation model AE 3007A engines, remove 
cone shafts from service prior to accumulating 9,500 cycles-since-
new (CSN) and replace with serviceable parts.
    (b) For Rolls-Royce Corporation model AE 3007C engines, remove 
cone shafts from service prior to accumulating 14,500 CSN and 
replace with serviceable parts.
    (c) For Roll-Royce Corporation models AE 3007A1, AE 3007A1/1, 
and AE 3007A1/2 engines, remove cone shafts from service prior to 
accumulating 7,500 CSN and replace with serviceable parts.
    (d) For Rolls-Royce Corporation model AE 3007A1/3 engines:
    (1) With compressor cone shafts P/N 23070729, serial number (SN) 
MM78599, MM78615, MM78632, MM78650, MM78651, MM78652, MM78653, 
MM78654, MM78655, MM78656, MM78657, MM78658, MM78659, MM78660, 
MM78661, MM78662, MM78663, MM78665 or higher, remove cone shafts 
from service prior to accumulating 9,300 CSN and replace with 
serviceable parts.
    (2) With compressor cone shafts P/N 23050728, or P/N 23070729 
having other than the S/N's listed in paragraph (d)(1) of this AD, 
remove cone shafts from service prior to accumulating 3,500 CSN and 
replace with serviceable parts.
    (e) For Rolls-Royce Corporation AE 3007A1P engines:
    (1) With compressor cone shafts P/N 23070729, SN MM78599, 
MM78615, MM78632, MM78650, MM78651, MM78652, MM78653, MM78654, 
MM78655, MM78656, MM78657, MM78658, MM78659, MM78660, MM78661, 
MM78662, MM78663, MM78665 or higher, remove cone shafts from service 
prior to accumulating 7,300 CSN and replace with serviceable parts.
    (2) With compressor cone shafts P/N 23050728, or P/N 23070729 
having other than the SN's listed in paragraph (e)(1) of this AD, 
remove cone shafts from service prior to accumulating 2,400 CSN and 
replace with serviceable parts.

New Life Limits

    (f) Paragraphs (a), (b), (c), (d) and (e) of this AD establish 
new, lower life limits for cone shafts, P/N's 23050728 and 23070729.
    (g) Except for the provisions of paragraph (h) of this AD, no 
cone shafts, P/Ns 23050728 and 23070729, may remain in service 
exceeding the life limits established in paragraphs (a), (b), (c), 
(d) and (e) of this AD.

Alternative Methods of Compliance

    (h) 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.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Chicago Aircraft Certification 
Office.

Special Flight Permits

    (i) Special flight permits may be issued in accordance 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the aircraft to a

[[Page 65429]]

location where the requirements of this AD can be done.

Effective Date

    (j) This amendment becomes effective on January 23, 2002.

    Issued in Burlington, Massachusetts, on December 7, 2001.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 01-30952 Filed 12-18-01; 8:45 am]
BILLING CODE 4910-13-P