Airworthiness Directives; International Aero Engines AG (IAE) V2500-A1 Series Turbofan Engines

Summary

This amendment adopts a new airworthiness directive (AD) that is applicable to International Aero Engines AG (IAE) V2500-A1 series turbofan engines. This action requires a one-time ultrasonic inspection of fan blade roots for cracks, and, if necessary, replacement of cracked fan blades with serviceable parts. This amendment is prompted by a report of dovetail root cracks visually detected on three fan blades from one engine during a routine inspection. The actions specified in this AD are intended to prevent fan blade root cracks, which could result in fan blade root failures, an uncontained engine failure, and damage to the aircraft.

Full text

SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to International Aero Engines AG (IAE) V2500-A1 series 
turbofan engines. This action requires a one-time ultrasonic inspection 
of fan blade roots for cracks, and, if necessary, replacement of 
cracked fan blades with serviceable parts. This amendment is prompted 
by a report of dovetail root cracks visually detected on three fan 
blades from one engine during a routine inspection. The actions 
specified in this AD are intended to prevent fan blade root cracks, 
which could result in fan blade root failures, an uncontained engine 
failure, and damage to the aircraft.

DATES: Effective October 21, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 21, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before December 7, 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-63-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
engineprop@faa.dot.gov''. Comments sent via the Internet must contain 
the docket number in the subject line.
    The service information referenced in this AD 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; or 
at the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

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: The Federal Aviation Administration (FAA) 
has received reports of dovetail root cracks visually detected on three 
fan blades from one engine during a routine turnaround inspection of an 
Airbus A320 aircraft powered with International Aero Engines AG (IAE) 
V2500-A1 turbofan engines. These cracks were located just inboard of 
the fan blade root/disc abutment area and extend to the front face of 
the blade root. Ultrasonic inspection of the other fan blades in this 
engine revealed blade root cracks in every fan blade initiating in high cycle fatigue from multi 
origins. Ultrasonic inspection of the fan disc from this engine also 
revealed small cracks in eleven disc posts. The FAA has determined that 
these fan blade root and fan disc post cracks were caused by an 
undetermined event that induced extremely high stresses into the blade 
roots and disc posts. A review of this engine history has not isolated 
any event other than a fan case acoustic panel loss six months prior to 
this routine inspection. However, other in-service V2500-A1 and -A5 
engines that experienced a fan case acoustic panel loss have completed 
the ultrasonic inspections without finding a fan blade root crack. As 
the investigation continues, IAE has recommended that the V2500-A1 
engine fleet ultrasonic inspect the fan blades. Approximately 95% of 
the V2500-A1 engine fleet have completed this fan blade ultrasonic 
inspection without finding fan blade root cracks. This condition, if 
not corrected, could result in fan blade root cracks, which could 
result in fan blade root failure, an uncontained engine failure, and 
damage to the aircraft.
    The FAA has reviewed and approved the technical contents of IAE 
Service Bulletin (SB) No. V2500-ENG-72-0316, Revision 2, dated August 
28, 1998, that describes procedures for ultrasonic inspection of fan 
blade roots for cracks.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of the same type design, this AD is 
being issued to prevent fan blade root cracks. This AD requires a one-
time ultrasonic inspection of fan blade roots for cracks, and, if 
necessary, replacement of cracked fan blades with serviceable parts. 
The actions are required to be accomplished in accordance with the SB 
described previously.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD 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-63-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866.
    It has been determined further that this action involves an 
emergency regulation under DOT Regulatory Policies and Procedures (44 
FR 11034, February 26, 1979). If it is determined that this emergency 
regulation otherwise would be significant under DOT Regulatory Policies 
and Procedures, a final regulatory evaluation will be prepared and 
placed in the Rules Docket. A copy of it, if filed, may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, 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 adding the following new 
airworthiness directive:

98-21-01  International Aero Engines AG: Amendment 39-10809. Docket 
98-ANE-63-AD.

    Applicability: International Aero Engines AG (IAE) V2500-A1 
series turbofan engines, installed on but not limited to Airbus A320 
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 (b) 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: Required as indicated, unless accomplished 
previously.
    To prevent fan blade root cracks, which could result in fan 
blade root failure, an uncontained engine failure, and damage to the 
aircraft, for those engines that have not previously been inspected 
in accordance with IAE Service Bulletin (SB) No. V2500-ENG-72-0316, 
dated May 15, 1998; or No. V2500-ENG-72-0316, Revision 1, dated June 
5, 1998; or No.V2500-ENG-72-0316, Revision 2, dated August 28, 1998, 
accomplish the following:
    (a) Within 150 hours time in service (TIS) after the effective 
date of this AD, perform a one-time ultrasonic inspection of fan 
blade roots for cracks, and, if necessary, replace cracked fan 
blades with serviceable parts, in accordance with IAE Service 
Bulletin (SB) No. V2500-ENG-72-0316, Revision 2, dated August 28, 
1998.
    (b) 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 requests 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 this airworthiness directive, 
if any, may be obtained from the Engine Certification Office.

    (c) 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 inspection requirements of this AD can be accomplished.
    (d) The actions required by this AD shall be done in accordance 
with the following IAE SB:

----------------------------------------------------------------------------------------------------------------
                  Document No.                     Pages    Revision                     Date
----------------------------------------------------------------------------------------------------------------
V2500-ENG-72-0316...............................      1-7          2  August 28, 1998.
    Total pages: 7.
----------------------------------------------------------------------------------------------------------------

This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Rolls-Royce Commercial Aero Engine 
Limited, P.O. Box 31, Derby, England, DE2488J, Attention: 
Publication Services ICL-TP. Copies may be inspected at the FAA, New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (e) This amendment becomes effective on October 21, 1998.
    Issued in Burlington, Massachusetts, on September 28, 1998.

Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 98-26529 Filed 10-5-98; 8:45 am]
BILLING CODE 4910-13-P  

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