[Federal Register Volume 74, Number 78 (Friday, April 24, 2009)]
[Proposed Rules]
[Pages 18662-18664]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-9443]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0174; Directorate Identifier 2008-NE-03-AD]
RIN 2120-AA64


Airworthiness Directives; CFM International, S.A. CFM56-5B1/P; -
5B2/P; -5B3/P; -5B3/P1; -5B4/P; -5B4/P1; -5B5/P; -5B6/P; -5B7/P; -5B8/
P; -5B9/P; -5B1/3; -5B2/3; -5B3/3; -5B4/3; -5B5/3; -5B6/3; -5B7/3; -
5B8/3; -5B9/3; -5B3/3B1; and -5B4/3B1 Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: This supplemental NPRM revises an earlier proposed 
airworthiness directive (AD), applicable to CFM International, S.A. 
CFM56-5B1/P; -5B2/P; -5B3/P; -5B3/P1; -5B4/P; -5B4/P1; -5B5/P; -5B6/P; 
-5B7/P; -5B8/P; and -5B9/P turbofan engines. That proposed AD would 
have required initial and repetitive eddy current inspections (ECIs) of 
certain part number (P/N) low-pressure (LP) turbine rear frames. That 
proposed AD resulted from a refined lifing analysis by the engine 
manufacturer that shows the need to identify initial and repetitive 
inspection thresholds for inspecting certain LP turbine rear frames. 
This supplemental NPRM revises the proposed AD to add two LP turbine 
rear frame P/Ns to the applicability, to add 11 engine models to the 
applicability, and to clarify the commercial and corporate engines/LP 
turbine rear frames applicability. This supplemental NPRM results from 
CFM International, S.A. revising the service information to add LP 
turbine rear frame P/Ns and engine models, and from comments received 
on the proposed AD. This supplemental NPRM also results from a refined 
lifing analysis by the engine manufacturer that shows the need to 
identify initial and repetitive inspection thresholds for inspecting 
certain LP turbine rear frames. We are proposing this AD to detect low-
cycle-fatigue cracks in the LP turbine rear frame, which could result 
in an engine separating from the airplane, causing damage to, and 
possibly leading to loss of control of, the airplane.

DATES: We must receive any comments on this proposed AD by June 8, 
2009.

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.
    You can get the service information identified in this proposed AD 
from CFM International, Technical Publications Department, 1 Neumann 
Way, Cincinnati, OH 45215; telephone (513) 552-2800; fax (513) 552-
2816.

FOR FURTHER INFORMATION CONTACT: Stephen Sheely, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
[email protected]; telephone (781) 238-7750; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

[[Page 18663]]

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-2008-0174; Directorate 
Identifier 2008-NE-03-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

    On April 29, 2008, we issued a proposal to amend part 39 of the 
Code of Federal Regulations (14 CFR part 39) to add an AD, applicable 
to CFM International, S.A. CFM56-5B1/P; -5B2/P; -5B3/P; -5B3/P1; -5B4/
P; -5B4/P1; -5B5/P; -5B6/P; -5B7/P; -5B8/P; and -5B9/P turbofan 
engines. The proposed AD published as an NPRM in the Federal Register 
on May 7, 2008 (73 FR 25597). That NPRM proposed to require initial and 
repetitive ECIs of certain P/N LP turbine rear frames.
    Since we issued that NPRM, we became aware of two additional LP 
turbine rear frame P/Ns affected, and 11 additional engine models 
affected that were not listed in the proposed AD applicability. CFM 
International, S.A. subsequently superseded Service Bulletin (SB) No. 
CFM56-5B S/B 72-0620, Revision 1, dated December 20, 2007, to add those 
LP turbine rear frame P/Ns and engine models. We added LP turbine rear 
frame P/Ns 338-171-751-0; and 338-171-752-0, and CFM56-5B1/3; -5B2/3; -
5B3/3; -5B4/3; -5B5/3; -5B6/3; -5B7/3; -5B8/3; -5B9/3; -5B3/3B1; and -
5B4/3B1 engine models to the applicability of the supplemental NPRM. We 
also clarified the commercial and corporate engines/LP turbine rear 
frames applicability. Because we added those CFM56 engine models and 
added those LP turbine rear frame P/Ns, this supplemental NPRM reopens 
the comment period to include those added engine models and added P/Ns, 
and to reference the superseding service bulletin.
    As we stated in the original proposed AD, CFM International, S.A. 
performed a refined lifing analysis that shows the need to identify 
initial and repetitive inspection thresholds for inspecting LP turbine 
rear frames. This condition, if not corrected, could result in an 
engine separating from the airplane, causing damage to, and possibly 
leading to loss of control of the airplane.

Comments

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

Consider Expanding the Engine Model Applicability

    One commenter, Virgin Airlines, requests that we consider expanding 
the applicability in the proposed AD by adding the CFM56-5B4/3 and 
CFM56-5B6/3 turbofan engines.
    We agree that those engines are affected. We added them to this 
supplemental NPRM.

Disagreement With Proposed AD Applicability

    One commenter, CFM International S.A., disagrees with the proposed 
AD applicability, specifically, the listing of all of the engines as 
certified for corporate application. They state that only the CFM56-
5B6/P and CFM56-5B7/P engine models certified for corporate application 
need to be covered by the proposed AD, because they were initially 
certified with a 22,500-cycle life. They now have a first inspection at 
19,000 cycles. All of the other -5B/P engine models in the corporate 
application were certified with the first inspection at 19,000 cycles, 
and do not need to be covered by the proposed AD.
    We agree. We corrected and clarified the applicability in the 
supplemental NPRM.

Request To Give Credit

    One commenter, Airbus, requests that we give credit for inspections 
previously done using CFM International, S.A. Service Bulletin No. 
CFM56-5B S/B 72-0620, dated May 3, 2007.
    We agree. We changed the supplemental NPRM to give credit for 
previous initial and repetitive inspections of turbine rear frames done 
before the effective date of the proposed AD using the original or 
Revision 1 of CFM International, S.A. Service Bulletin No. CFM56-5B S/B 
72-0620.

Correction to How Many Engines Affected

    Since we issued the original NPRM, we discovered that we 
incorrectly estimated how many engines are affected. We stated that 
about 426 engines are affected that are installed on airplanes of U.S. 
registry. That number actually reflects how many engines are installed 
on airplanes of U.S. registry, regardless of the LP turbine rear frame 
P/N. We corrected the estimated number of affected engines to 282, 
which reflects those engines with the affected LP turbine rear frames 
listed in this supplemental NPRM.

FAA's Determination and Requirements of the Proposed AD

    We 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 will require initial 
and repetitive ECIs of certain P/N LP turbine rear frames. This 
proposed AD results from a refined lifing analysis by the engine 
manufacturer that shows the need to identify initial and repetitive 
inspection thresholds for inspecting certain LP turbine rear frames. 
This proposed AD would require you to use the service information 
described previously to perform the inspections.

Costs of Compliance

    We estimate that this proposed AD would affect 282 CFM56-5B series 
turbofan engines installed on airplanes of U.S. registry. We estimate 
that it would take about 3 work-hours to perform an eddy current 
inspection of an LP turbine rear frame. The average labor rate is $80 
per work-hour. A replacement LP turbine rear frame costs

[[Page 18664]]

about $102,240. If all 282 LP turbine rear frames needed replacement, 
we estimate the total cost of the proposed AD to U.S. operators to be 
$28,899,360.

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 
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. 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. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

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:

CFM International, S.A.: Docket No. FAA-2008-0174; Directorate 
Identifier 2008-NE-03-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by June 8, 
2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to:
    (1) CFM International, S.A. turbofan engines with a low-pressure 
(LP) turbine rear frame, part number (P/N) 338-171-703-0; 338-171-
704-0; 338-171-705-0; or 338-171-706-0 installed, as follows:
    (i) Commercial application CFM56-5B1/P; -5B2/P; -5B3/P; -5B3/P1; 
-5B4/P; -5B4/P1; -5B5/P; -5B6/P; -5B7/P; -5B8/P; -5B9/P turbofan 
engines.
    (ii) Corporate application CFM56-5B6/P and -5B7/P turbofan 
engines.
    (2) CFM International, S.A. turbofan engines with an LP turbine 
rear frame, P/N 338-171-751-0; or 338-171-752-0 installed, on 
corporate and commercial applications of CFM56-5B1/P; -5B2/P; -5B3/
P; -5B3/P1; -5B4/P; -5B4/P1; -5B5/P; -5B6/P; -5B7/P; -5B8/P; -5B9/P; 
-5B1/3; -5B2/3; -5B3/3; -5B4/3; -5B5/3; -5B6/3; -5B7/3; -5B8/3; -
5B9/3; -5B3/3B1; and -5B4/3B1 turbofan engines.
    (3) These engines are installed on, but not limited to, Airbus 
A318, A319, A320, and A321 series airplanes.

Unsafe Condition

    (d) This AD results from a refined lifing analysis by the engine 
manufacturer that shows the need to identify initial and repetitive 
inspection thresholds for inspecting certain LP turbine rear frames. 
We are issuing this AD to detect low-cycle-fatigue cracks in the LP 
turbine rear frame, which could result in an engine separating from 
the airplane, causing damage to, and possibly leading to loss of 
control of 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.

Initial Inspection

    (f) Perform an initial eddy current inspection (ECI) of the LP 
turbine rear frame using paragraphs 3.A. through 3.A.(7)(d) of the 
Accomplishment Instructions of CFM International, S.A. Service 
Bulletin (SB) No. CFM56-5B S/B 72-0620, Revision 2, dated December 
1, 2008, at the following compliance times:
    (1) For commercial engine applications, within 25,000 cycles-
since-new (CSN) on the LP turbine rear frame.
    (2) For corporate engine applications, within 19,000 CSN on the 
LP turbine rear frame.
    (3) For engines with unknown LP turbine rear frame CSN, within 
300 cycles-in-service from the effective date of this AD.

Repetitive Inspections

    (g) Perform repetitive ECIs of the LP turbine rear frame using 
paragraphs 3.A. through 3.A.(7)(d) of the Accomplishment 
Instructions of CFM International, S.A. SB No. CFM56-5B S/B 72-0620, 
Revision 2, dated December 1, 2008. Use the inspection intervals in 
paragraph 3.A.(8) of the Accomplishment Instructions of CFM 
International, S.A. SB No. CFM56-5B S/B 72-0620, Revision 2, dated 
December 1, 2008.

LP Turbine Rear Frame Removal Criteria

    (h) Remove LP turbine rear frames from service that have a 
single crack length of 2.56 inches (65 mm) or longer, or multiple 
cracks with an accumulated crack length of 2.56 inches (65 mm) or 
longer.

Previous Credit

    (i) Initial and repetitive inspections done before the effective 
date of this AD using CFM International, S.A. SB No. CFM56-5B S/B 
72-0620, dated May 3, 2007, or SB No. CFM56-5B S/B 72-0620, Revision 
1, dated December 20, 2007, comply with the initial and repetitive 
inspection requirements specified in this AD. Operators must 
continue performing the repetitive inspections required in paragraph 
(g) 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) European Aviation Safety Agency AD 2007-0221, dated August 
13, 2007, also addresses the subject of this AD.
    (l) Contact Stephen Sheely, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
[email protected]; telephone (781) 238-7750; fax (781) 238-
7199, for more information about this AD.

    Issued in Burlington, Massachusetts, on April 17, 2009.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E9-9443 Filed 4-23-09; 8:45 am]
BILLING CODE 4910-13-P