Document ID: FAA-2008-1245-0006
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; CFM International S.A. Model CFM56 Turbofan Engines
Posted Date: 2009-05-19T04:00Z

[Federal Register: May 19, 2009 (Volume 74, Number 95)]
[Rules and Regulations]               
[Page 23305-23307]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19my09-2]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-1245; Directorate Identifier 2008-NE-27-AD; 
Amendment 39-15912; AD 2009-11-02]
RIN 2120-AA64

 
Airworthiness Directives; CFM International S.A. Model CFM56 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for CFM 
International S.A. CFM56-2, CFM56-3, CFM56-5A, CFM56-5B, CFM56-5C, and 
CFM56-7B series turbofan engines with certain part number (P/N) and 
serial number (SN) high-pressure compressor (HPC) 4-9 spools installed. 
This AD requires removing certain HPC 4-9 spools listed by P/N and SN 
in this AD. This AD results from reports of certain HPC 4-9 spools that 
Propulsion Technology LLC (PTLLC) improperly repaired and returned to 
service. We are issuing this AD to prevent cracking of the HPC 4-9 
spool, which could result in possible uncontained failure of the spool 
and damage to the airplane.

DATES: This AD becomes effective June 23, 2009.

ADDRESSES: The Docket Operations office is located at Docket Management 
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, 
SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-
0001.

FOR FURTHER INFORMATION CONTACT: Stephen K. Sheely, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
stephen.k.sheely@faa.gov; telephone (781) 238-7750; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed AD. The proposed AD applies to CFM International S.A. 
CFM56-2, CFM56-3, CFM56-5A, CFM56-5B, CFM56-5C, and CFM56-7B series 
turbofan engines with certain P/N and SN HPC 4-9 spools installed. We 
published the proposed AD in the Federal Register on November 26, 2008 
(73 FR 71951). That action proposed to require removing certain HPC 4-9 
spools that have a P/N and SN listed in Table 1 of this AD before 
accumulating 8,900 cycles since repair at PTLLC or within 1,100 cycles 
from the effective date of this AD, whichever occurs later.

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 AD, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Operations office (telephone (800) 647-5527) is provided in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Incorrect SN in Table 1 of the Proposed AD

    Three commenters, the Air Transport Association (ATA), United 
Airlines, and CFM International, point out a typographical error in the 
SN for a 4-9 spool, P/N 1590M29G01. They state that the Special 
Airworthiness Information Bulletin (SAIB) NE-08-17 shows SN GWNFY924 
for that P/N and the proposed rule shows SN GWNFY824 for the same P/N.
    We agree. Serial number GWNFY924 is the correct SN. We changed 
Table 1, P/N 1590M29G01 SN ``GWNFY824,'' to ``GWNFY924'' in this AD.

Request To Clarify the Relationship Between SAIB NE-08-17 and the 
Proposed AD

    One commenter, the ATA, suggests the proposed AD doesn't show a 
clear relationship between its requirements and those contained in SAIB 
NE-08-17. The ATA suggests we provide a clarification and a better 
understanding of why we wrote SAIB NE-08-17 and the proposed rule. The 
ATA also asks if the recommendations or the hardware listed in SAIB NE-
08-17 is still in effect.
    We partially agree. The proposed AD specifies the same twenty-six 
4-9 spools as SAIB NE-08-17. Special Airworthiness Information Bulletin 
NE-08-17 still provides recommendations for dispositioning other parts 
listed in that SAIB. However, we don't require removing the hardware 
listed in SAIB NE-08-17, other than the 4-9 spools. We didn't change 
the AD.

[[Page 23306]]

Request To Delete ``Seal Tooth Plasma Overspray'' Statement From 
Discussion

    One commenter, CFM International, asks us to delete ``Seal tooth 
plasma overspray between the seal teeth, which is not permitted by the 
engine overhaul manual, and'' from the Discussion Section. CFM 
International states that the overhaul manual does allow plasma 
overspray between the seal teeth.
    We agree that the overhaul manual allows plasma overspray between 
the seal teeth. However, the Discussion Section is not included in the 
AD. We didn't change the AD.

Request To Include Instructions for Dispositioning the Removed 4-9 
Spool

    One commenter, Japan Airlines, states that we include a prohibition 
for installing the affected 4-9 spools, but we don't specify what to do 
with the 4-9 spools removed as specified in the proposed AD. They ask 
us to provide instructions to disposition the removed 4-9 spools.
    We don't agree. The proposed rule requires removing from service, 
certain 4-9 spools, which removes the unsafe condition. The included 
installation prohibition resolves our remaining regulatory concerns. 
How operators recycle metal is beyond the scope of an AD, so long as 
the excluded part doesn't find its way back into service. We didn't 
change the AD.

Request To Clarify the Compliance Times

    One commenter, the Boeing Company, asks us to clarify the 
compliance times for removing the affected 4-9 spools. Boeing suggests 
that, as written, the compliance times of ``before accumulating 8,900 
cycles-since-repair at PTLLC or within 1,100 cycles after the effective 
date of this AD,'' could allow up to 10,000 cycles to accumulate on an 
engine before an operator has to take corrective action.
    We agree. That is what we intended. We didn't change the AD.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    We estimate that this AD will affect 26 engines installed on 
airplanes of U.S. registry. We also estimate that it will take about 
410 work-hours per engine to perform the required actions, and that the 
average labor rate is $80 per work-hour. Required parts will cost about 
$227,500 per engine. Based on these figures, we estimate the total cost 
of the AD to U.S. operators to be $6,767,800.

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 AD will not have federalism 
implications under Executive Order 13132. This AD will 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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and
    (3) 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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. 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, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2009-11-02 CFM International S.A.: Amendment 39-15912. Docket No. 
FAA-2008-1245; Directorate Identifier 2008-NE-27-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective June 23, 
2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to CFM International S.A. CFM56-2, CFM56-3, 
CFM56-5A, CFM56-5B, CFM56-5C, and CFM56-7B series turbofan engines 
with a high-pressure compressor (HPC) 4-9 spool that has a part 
number (P/N) and serial number (SN) specified in Table 1 of this AD, 
installed. These engines are installed on, but not limited to, 
Airbus A319, A320, and A340 airplanes and Boeing 737 airplanes.

                  Table 1--HPC 4-9 Spools by P/N and SN
------------------------------------------------------------------------
             HPC 4-9 spool P/N                    HPC 4-9 spool SN
------------------------------------------------------------------------
9513M93G08................................  MPON1641
1590M29G01................................  GWN0087D
1590M29G01................................  GWN00MG2
1590M29G01................................  GWN011LG
1590M29G01................................  GWN01285
1590M29G01................................  GWN021JC
1590M29G01................................  GWNFY923
1590M29G01................................  GWNFY924
1590M29G01................................  GWNPA756
1590M29G01................................  GWNPG015
1590M29G01................................  GWNWC515
1590M29G01................................  GWNWR523
1590M29G01................................  GWNWT631
1590M29G01................................  GWNYC495
1588M89G03................................  GWN03K1R
1588M89G03................................  GWN03N61
1588M89G03................................  GWN03N6C
1588M89G03................................  GWN040L9
1588M89G03................................  GWN0468N
1588M89G03................................  GWN05AMO
1277M97G02................................  GWNE1298
1277M97G02................................  GWNE1564
1277M97G02................................  GWNJ7891
1277M97G02................................  GWNT4187
9513M93G11................................  GWNB3373
1358M94G01................................  GWNU0169
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD results from reports of certain HPC 4-9 spools that 
Propulsion Technology LLC (PTLLC) improperly repaired and returned 
to service. We are issuing this AD to prevent cracking of the HPC 4-
9 spool, which could result in possible uncontained

[[Page 23307]]

failure of the spool 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.

Removing the HPC 4-9 Spool

    (f) Remove HPC 4-9 spools from service that have a P/N and S/N 
listed in Table 1 of this AD before accumulating 8,900 cycles-since-
repair at PTLLC or within 1,100 cycles from the effective date of 
this AD, which ever occurs later.

Installation Prohibition

    (g) After the effective date of this AD, do not install any 
engine with an HPC 4-9 spool that has a P/N and SN specified in 
Table 1 of this AD.

Alternative Methods of Compliance

    (h) 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

    (i) Contact Stephen K. Sheely, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
stephen.k.sheely@faa.gov; telephone (781) 238-7750; fax (781) 238-
7199, for more information about this AD.

Material Incorporated by Reference

    (j) None.

    Issued in Burlington, Massachusetts, on May 13, 2009.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E9-11554 Filed 5-18-09; 8:45 am]

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