[Federal Register Volume 63, Number 187 (Monday, September 28, 1998)]
[Proposed Rules]
[Pages 51545-51546]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-25777]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-08-AD]
RIN 2120-AA64


Airworthiness Directives; International Aero Engines AG (IAE) 
V2500-A5/-D5 Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to International Aero Engines AG 
(IAE) V2500-A5/-D5 series turbofan engines. This proposal would require 
removal from service of certain high pressure compressor (HPC) stage 9-
12 drums prior to reaching the new reduced cyclic life limits, and 
replacement with serviceable parts. This proposal is prompted by the 
reduction of the life limit for certain IAE V2500 HPC stage 9-12 drums 
due to higher stresses in this part than originally predicted. The 
actions specified by the proposed AD are intended to prevent HPC stage 
9-12 drum failure, which could result in an uncontained engine failure 
and damage to the aircraft.

DATES: Comments must be received by November 27, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 98-ANE-08-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain 
the docket number in the subject line. Comments may be inspected at 
this location between 8 a.m. and 4:30 p.m., Monday through Friday, 
except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Rolls-Royce Commercial Aero Engine Limited, P.O. Box 31, 
Derby, England, DE2488J, Attention: Publication Services ICL-TP. This 
information may be examined at the FAA, New England Region, Office of 
the Regional Counsel, 12 New England Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT:
Diane Cook, Aerospace Engineer, Engine Certification Office, FAA, 
Engine and Propeller Directorate, 12 New England Executive Park, 
Burlington, MA 01803-5299; telephone (781) 238-7133, fax (781) 238-
7199.

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 should 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-ANE-08-AD.'' The postcard will be date stamped and 
returned to the commenter.

[[Page 51546]]

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, New England Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 98-ANE-08-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.

Discussion

    The Federal Aviation Administration (FAA) has been made aware that 
the stresses on certain International Aero Engines AG (IAE) V2500 
Series High Pressure Compressor (HPC) stage 9-12 drums are higher than 
originally predicted. Based on improved analytical stress analyses and 
test results the FAA has determined that certain HPC stage 9-12 drums 
have a lower cyclic life than originally calculated depending on the 
engine model and thrust rating. This condition, if not corrected, could 
result in an HPC stage 9-12 drum failure, which could result in an 
uncontained engine failure and damage to the aircraft.
    The FAA has reviewed and approved the technical contents of IAE 
Service Bulletin (SB) N. V2500-ENG-72-0293, dated December 19, 1997, 
that describes lower cyclic life limits of the HPC stage 9-12 drum 
depending on the engine model and thrust rating.
    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 removal from service of certain HPC stage 9-
12 drums prior to reaching new, reduced cyclic life limits, and 
replacement with serviceable parts. The actions would be required to be 
accomplished in accordance with the SB described previously.
    There are approximately 400 engines of the affected design in the 
worldwide fleet. The FAA estimates that 162 engines installed on 
aircraft of U.S. registry would be affected by this proposed AD, that 
it would take approximately no additional work hours to accomplish the 
proposed actions. Required parts, on a prorated basis, would cost 
approximately $49,000 per engine. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$7,900,000.
    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 
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 captain 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 proposed to amend 
part 39 of the Federal Aviation Regulation (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:

International Aero Engines: Docket No. 98-ANE-08-AD.

    Applicablity: International Aero Engines AG (IAE) Models V2522-
A5, V2524-A5, V2527-A5, V2527E-A5, V2530-A5, V2533-A5, V2525-D5, 
V2528-D5 turbofan engines, installed on but not limited to Airbus 
Industrie A319, A320, A321 series and McDonnell Douglas MD-90 series 
aircraft.

    Note 1: This airworthiness directive (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 (d) of this AD. The request should include an assessment 
of the effect of the modification, alternation, 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 high pressure compressor (HPC) stage 9-12 drum 
failure, which could result in an uncontained engine failure and 
damage to the aircraft, accomplish the following:
    (a) Remove for service HPC stage 9-12 drums, part number (P/N) 
6A4156, operated in a single engine model at a single thrust rating 
prior to accumulating the new, reduced cyclic life limits, which are 
dependent upon the engine installation and thrust rating, as 
described in Table 1 of IAE Service Bulletin (SB) No. V2500-ENG-72-
0293, dated December 19, 1997, and replace with a serviceable part.
    (b) Remove from service HPC stage 9-12 drums, P/N 6A4156, 
installed in engines which operate at a mixture of thrust ratings, 
prior to accumulating the cyclic life limit of the highest thrust 
rating employed, as described in Table 1 of IAE SB No. V2500-ENG-72-
0293, dated December 19, 1997, and replace with a serviceable part. 
The use of an HPC stage 9-12 drum, P/N 6A4156, at a higher thrust 
rating for even a single flight invokes the cyclic life limit 
applicable for the higher thrust rating.
    (c) Remove from service HPC stage 9-12 drums, P/N 6A4156, 
removed from one engine model and installed into another engine 
model or operated at different thrust ratings prior to accumulating 
the applicable component cyclic life limit for the engine model with 
the highest thrust rating, as described in Table 1 of IAE SB No. 
V2500-ENG-72-0293, dated December 19, 1997, regardless of the cycles 
in service at this rating, and replace with a serviceable part.
    (d) This AD establishes a new cyclic retirement life limits for 
HPC stage 9-12 drums, part number (P/N) 6A4156. Thereafter, except 
as provided in paragraph (e) of this AD, no alternative cyclic 
retirement life limits may be approved for HPC stage 9-12 drums.
    (e) 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, Engine Certification Office. 
Operators shall submit their request through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, Engine Certification Office.

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

    (f) 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.

    Issued in Burlington, Massachusetts, on September 21, 1998.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 98-25777 Filed 8-25-98; 8:45 am]
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