```

[Federal Register Volume 75, Number 225 (Tuesday, November 23, 2010)]
[Proposed Rules]
[Pages 71373-71375]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-29450]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0494; Directorate Identifier 2010-NE-20-AD]
RIN 2120-AA64

Airworthiness Directives; International Aero Engines V2500-A1, 
V2522-A5, V2524-A5, V2525-D5, V2527-A5, V2527E-A5, V2527M-A5, V2528-D5, 
V2530-A5, and V2533-A5 Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for International Aero Engines (IAE) V2500-A1, V2522-A5, V2524-A5, 
V2525-D5, V2527-A5, V2527E-A5, V2527M-A5, V2528-D5, V2530-A5, and 
V2533-A5 turbofan engines. This proposed AD would require initial and 
repetitive 360[deg] borescope inspections of high-pressure turbine 
(HPT) stage 1 blade outer air seal segments for evidence of certain 
distress conditions. This proposed AD would also require incorporation 
of improved durability stage 1 blade outer air seal segments at the 
next exposure to the HPT module subassembly, as terminating action to 
the repetitive inspections. This proposed AD results from three reports 
received of HPT case burn-through events, numerous shop reports of loss 
of stage 1 blade outer air seal segments, and HPT case bulging. We are 
proposing this AD to prevent HPT case burn-through, uncontrolled under-
cowl engine fire, and damage to the airplane.

DATES: We must receive any comments on this proposed AD by January 24, 
2011.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.

[[Page 71374]]

    Contact International Aero Engines AG, 400 Main Street, East 
Hartford, CT 06108; telephone: (860) 565-5515; fax: (860) 565-5510, for 
a copy of the service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Carlos Fernandes, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
carlos.fernandes@faa.gov; telephone (781) 238-7189; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2010-0494; Directorate 
Identifier 2010-NE-20-AD'' in the subject line of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of the proposed AD. We will consider 
all comments received by the closing date and may amend the proposed AD 
in light of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, the name of the individual who 
sent the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78).

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

Discussion

    Since August 2006 we have received three reports of IAE V2500 
series engines experiencing HPT case burn-through events. There have 
also been numerous shop reports of loss of stage 1 blade outer air seal 
segments, and reports of HPT case bulging. Investigation revealed the 
cause to be due to HPT stage 1 blade outer air seal distress. Distress 
initially starts with surface erosion and cracking of the blade outer 
air seal segments. Continued engine operation then leads to burn-
through, radial bowing of the segments into the gas path, contact with 
the HPT stage 1 blades, and loss of the segments from the HPT case. 
This condition, if not corrected, could then result in HPT case burn-
through, uncontrolled under-cowl engine fire, and damage to the 
airplane.

Relevant Service Information

    We have reviewed and approved the technical contents of IAE Service 
Bulletin (SB) No. V2500-ENG-72-0580, Revision 2, dated August 12, 2010, 
that describes procedures for initial and repetitive 360[deg] borescope 
inspections of stage 1 blade outer air seal segments for evidence of 
distress. We have also reviewed and approved IAE SB No. V2500-ENG-72-
0483, Revision 3, dated January 7, 2009, and IAE SB No. V2500-ENG-72-
0542, Revision 1, dated January 7, 2009, which incorporate improved 
durability stage 1 blade outer air seal segments.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. We are proposing this AD, which would require 
initial and repetitive 360[deg] borescope inspections of HPT stage 1 
blade outer air seal segments for evidence of distress. This proposed 
AD would also require incorporation of improved design stage 1 blade 
outer air seal segments at the next exposure to the HPT module 
subassembly. The proposed AD would require you to use the service 
information described previously to perform these actions.

Costs of Compliance

    We estimate that this proposed AD would affect 34 V2500 A1 series 
and 510 V2500 A5/D5 series engines installed on airplanes of U.S. 
registry. We also estimate that it would take about 3 work-hours per 
engine to perform one proposed inspection, about 3 work-hours per 
engine to install the improved durability stage 1 blade outer air seal 
segments, and that the average labor rate is $85 per work-hour. 
Required parts would cost about $150,882 (V2500 A1 series) and $155,195 
(V2500 A5/D5 series), per engine. Based on these figures, we estimate 
the total cost of the proposed AD to U.S. operators to be $84,556,878.

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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed AD:
    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. Would 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 regulatory evaluation of the estimated costs to 
comply with this proposed AD. 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, Incorporation by 
reference, Safety.

[[Page 71375]]

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

International Aero Engines: Docket No. FAA-2010-0494; Directorate 
Identifier 2010-NE-20-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 24, 
2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to International Aero Engines (IAE) V2500-
A1, V2522-A5, V2524-A5, V2525-D5, V2527-A5, V2527E-A5, V2527M-A5, 
V2528-D5, V2530-A5, and V2533-A5 turbofan engines. These engines are 
installed on, but not limited to, Airbus A319, A320, A321, and 
McDonnell Douglas MD-90 airplanes.

Unsafe Condition

    (d) This AD results from three reports received of high-pressure 
turbine (HPT) case burn-through events. There have also been 
numerous shop reports of loss of stage 1 blade outer air seal 
segments, and HPT case bulging. We are issuing this AD to prevent 
HPT case burn-through, uncontrolled under-cowl engine fire, and 
damage to the airplane.

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.
    (f) For engines that have incorporated IAE Service Bulletin (SB) 
No. V2500-ENG-72-0483, Revision 3 or earlier, or IAE SB No. V2500-
ENG-72-0542, Revision 1 or earlier, no further action is required.

Borescope Inspections

    (g) Perform 360[deg] borescope inspections of the HPT stage 1 
blade outer air seal segments for evidence of the distress 
conditions listed in Appendix D of IAE SB No. V2500-ENG-72-0580, 
Revision 2, dated August 12, 2010.
    (1) For V2525-D5 and V2528-D5 turbofan engines:
    (i) Inspect within 1,000 operating hours after the engine meets 
all criteria as defined in Table 1 of this AD, or within 600 
operating hours after the effective date of this AD, whichever is 
greater.
    (ii) Thereafter, re-inspect within every 1,000 operating hours 
or as defined in Appendix D of IAE SB No. V2500-ENG-72-0580, 
Revision 2, dated August 12, 2010, whichever is less.
    (iii) Use Accomplishment Instructions paragraphs 3.B.(1) through 
3.B.(3), and Appendices A through D of IAE SB No. V2500-ENG-72-0580, 
Revision 2, dated August 12, 2010, to do these inspections.
    (2) For V2500-A1, V2522-A5, V2524-A5, V2527-A5, V2527E-A5, 
V2527M-A5, V2530-A5, and V2533-A5 turbofan engines:
    (i) Inspect within 1,200 operating hours after the engine meets 
all criteria as defined in Table 1 of this AD, or within 600 
operating hours after the effective date of this AD, whichever is 
greater.
    (ii) Thereafter, re-inspect within every 1,200 operating hours 
or as defined in Appendix D of IAE SB No. V2500-ENG-72-0580, 
Revision 2, dated August 12, 2010, whichever is less.
    (iii) Use Accomplishment Instructions paragraphs 3.A.(1) through 
3.A.(3), and Appendices A through D of IAE SB No. V2500-ENG-72-0580, 
Revision 2, dated August 12, 2010, to do these inspections.

                  Table 1--Stage 1 Blade Outer Air Seal Segment Inspection Compliance Criteria
----------------------------------------------------------------------------------------------------------------
                                                           Stage 1 blade      Stage 1 blade
                                                           outer air seal     outer air seal      Exhaust gas
                                                          segments hours-    segments cycles-     temperature
                      Engine model                          since-new or       since-new or      margin degrees
                                                         since-last-repair  since-last-repair    celsius (less
                                                           (greater than)     (greater than)         than)
----------------------------------------------------------------------------------------------------------------
A1.....................................................              6,000              3,800                 45
A5.....................................................              6,000              3,500                 45
D5.....................................................              5,000              3,500                 45
----------------------------------------------------------------------------------------------------------------

     (h) Exhaust Gas Temperature Margin is defined as the expected 
margin during a sea-level takeoff on a 30-degree Celsius Outside Air 
Temperature Day.

Terminating Action

    (i) As terminating action to the repetitive 360[deg] borescope 
inspections required in paragraphs (g)(1)(ii) and (g)(2)(ii) above, 
install improved durability stage 1 blade outer air seal segments at 
the next HPT module subassembly exposure.
    (1) For V2500-A1 turbofan engines, use paragraphs 1.B., 
Concurrent Requirements, and paragraphs 3.(1) through 3.(2)(b) of 
the Accomplishment Instructions of IAE SB No. V2500-ENG-72-0542, 
Revision 1, dated January 7, 2009, to do the installation.
    (2) For V2522-A5, V2524-A5, V2525-D5, V2527-A5, V2527E-A5, 
V2527M-A5, V2528-D5, V2530-A5, and V2533-A5 turbofan engines, use 
paragraphs 1.B., Concurrent Requirements, and paragraphs 3.(1) 
through 3.(2)(b) of the Accomplishment Instructions of IAE SB No. 
V2500-ENG-72-0483, Revision 3, dated January 7, 2009, to do the 
installation.
    (3) Both IAE SBs No. V2500-ENG-72-0542, Revision 1, and SB No. 
V2500-ENG-72-0483, Revision 3, require modification of the stage 1 
HPT support assembly before installing the new blade outer air seal 
segments. You must complete the modification using those SBs, as 
applicable to the appropriate engine model, to properly perform the 
mandatory terminating action of this AD.

Alternative Methods of Compliance

    (j) 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

    (k) Contact Carlos Fernandes, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
mark.riley@faa.gov; telephone (781) 238-7189; fax (781) 238-7199, 
for more information about this AD.
    (l) Contact International Aero Engines AG, 400 Main Street, East 
Hartford, CT 06108; telephone: (860) 565-5515; fax: (860) 565-5510, 
for a copy of the service information referenced in this AD.

    Issued in Burlington, Massachusetts, on November 16, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2010-29450 Filed 11-22-10; 8:45 am]
BILLING CODE 4910-13-P
```