

[Federal Register: February 5, 2008 (Volume 73, Number 24)]
[Proposed Rules]               
[Page 6638-6640]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr05fe08-27]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0169; Directorate Identifier 2007-NE-45-AD]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG, 
BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. This proposed AD results from mandatory 
continuing airworthiness information (MCAI) issued by another country 
to identify and correct an unsafe condition on Rolls-Royce Deutschland 
Ltd & Co KG, BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 
turbofan engines. The MCAI states the following:

    The application of most recent 3D FEM modeling has resulted in 
the need to reconsider the disc lives as currently shown in the Time 
Limits Manual. The current Post Certification Life Statement for the 
low pressure (LP) compressor (fan) disc assembly revises the 
Declared Safe Cyclic Life (DSCL) from 33,000 flight cycles to 25,000 
flight cycles for both the BR715 LP (fan) disc assembly Part No. (P/
N) BRH10048 and BR715 LP compressor (fan) disc assembly P/N 
BRH19253, when installed in the BR700-715A1-30 engine model and 
operated against the Hawaiian Flight Mission.

    The proposed AD would require revising the maximum approved life 
limit for both the BR715 LP compressor (fan) disc assembly P/N BRH10048 
and BR715 LP compressor (fan) disc assembly P/N BRH19253, from 33,000 
flight cycles to 25,000 flight cycles, if ever operated against the 
Hawaiian Flight Mission and removing LP compressor (fan) disc 
assemblies from service that exceed the maximum approved life limit 
before further flight. This condition, if not corrected, could result 
in uncontained failure of the LP compressor (fan) disc assembly and 
damage to the airplane.

DATES: We must receive comments on this proposed AD by March 6, 2008.

ADDRESSES: You may send comments by any of the following methods:
     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.

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.

FOR FURTHER INFORMATION CONTACT: Jason Yang, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
Jason.yang@faa.gov; telephone (781) 238-7747; fax (781) 238-7199.


SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2007-0169; 
Directorate Identifier 2007-NE-45-AD'' at the beginning of

[[Page 6639]]

your comments. We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of this 
proposed AD. We will consider all comments received by the closing date 
and may amend this proposed AD based on 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 we 
receive about this proposed AD.

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the European Community, has issued EASA Airworthiness 
Directive 2007-0116-E, dated May 4, 2007 (referred to after this as 
``the MCAI''), to correct an unsafe condition for the specified 
products. The MCAI states:

    The application of most recent 3D FEM modeling has resulted in 
the need to reconsider the disc lives as currently shown in the Time 
Limits Manual. The current Post Certification Life Statement for the 
low pressure (LP) compressor (fan) disc assembly revises the 
Declared Safe Cyclic Life (DSCL) from 33,000 flight cycles to 25,000 
flight cycles for both the BR715 LP (fan) disc assembly P/N BRH10048 
and BR715 LP compressor (fan) disc assembly P/N BRH19253, when 
installed in the BR700-715A1-30 engine model and operated against 
the Hawaiian Flight Mission.

    You may obtain further information by examining the MCAI in the AD 
docket.

FAA's Determination and Requirements of This Proposed AD

    This product has been approved by the aviation authority of 
Germany, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with Germany, they have notified us of the 
unsafe condition described in the MCAI AD and service information 
referenced above. We are proposing this AD because we evaluated all 
information provided by EASA and determined the unsafe condition exists 
and is likely to exist or develop on other products of the same type 
design. This proposed AD would require:
     Revising the maximum approved life limit for both the 
BR715 LP compressor (fan) disc assembly P/N BRH10048 and BR715 LP 
compressor (fan) disc assembly P/N BRH19253, in the Time Limits Manual 
No. T-715-3BR; from 33,000 flight cycles to 25,000 flight cycles, if 
ever operated against the Hawaiian Flight Mission; and
     Removing LP compressor (fan) disc assemblies from service 
that exceed the maximum approved life limit before further flight.
     Applying the pro rate calculations and completing the Life 
Limited Part Tracking Sheet, using the revised Hawaiian Flight Mission 
maximum life limit of 25,000 flight cycles and checking if their 
consumed life has exceeded maximum approved life of the Flight Mission 
currently installed in; and
     Before further flight, removing LP compressor disc 
assemblies from service that do not pass the check.

Costs of Compliance

    We estimate that this proposed AD would affect about 240 engines 
installed on aircraft of U.S. registry. This proposed LP compressor 
(fan) disc assembly removal does not impose any additional labor costs 
if performed at the time of scheduled engine overhaul. We also estimate 
that it will take about one work-hour per engine to calculate and re-
establish the achieved cyclic life for an LP compressor (fan) disc 
assembly, and that the average labor rate is $80 per work-hour. We 
estimate that the prorate cost of the life reduction per engine will be 
$33,000. Total cost of this proposed AD is, therefore, $7,939,200.

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 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 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. 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 regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA 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 AD:

Rolls-Royce Deutschland Ltd & Co KG (formerly BMW Rolls-Royce GmbH, 
and BMW Rolls-Royce Aero Engines): Docket No. FAA-2007-0169; 
Directorate Identifier 2007-NE-45-AD.

Comments Due Date

    (a) We must receive comments by March 6, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce Deutschland Ltd & Co KG 
(RRD), BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 turbofan 
engines, with a low pressure (LP) compressor disc assembly, part 
number (P/N) BRH10048 or P/N BRH19253, when installed in the BR700-
715A1-30 engine model and operated against the Hawaiian Flight 
Mission. These engines are installed on, but not limited to, 
McDonnell Douglas Corporation model 717-200 airplanes.

Reason

    (d) The mandatory continuous airworthiness information (MCAI) 
states:

    The application of most recent 3D FEM modeling has resulted in 
the need to reconsider the disc lives as currently shown in the Time 
Limits Manual. The current Post Certification Life Statement for the 
low pressure (LP) compressor (fan) disc assembly

[[Page 6640]]

revises the Declared Safe Cyclic Life (DSCL) from 33,000 flight 
cycles to 25,000 flight cycles for both the BR715 LP (fan) disc 
assembly P/N BRH10048 and BR715 LP compressor (fan) disc assembly P/
N BRH19253, when installed in the BR700-715A1-30 engine model and 
operated against the Hawaiian Flight Mission.

    This condition, if not corrected, could result in uncontained 
failure of the LP compressor (fan) disc assembly and damage to the 
airplane.

Actions and Compliance

    (e) No later than 100 flight cycles after the effective date of 
this AD, do the following actions, unless already done.

BR700-715A1-30 Turbofan Engines

    (1) For BR700-715A1-30 turbofan engines, amend the Airworthiness 
Limitations Section of the Time Limits Manual SUBTASK 05-10-01-860-
016, (Hawaiian Flight Mission Only) by revising the ``GIVEN LIFE A1-
30 RATING (FLIGHT CYCLES)'' for both the LP compressor (fan) disc 
assembly P/N BRH10048 and LP compressor (fan) disc assembly P/N 
BRH19253 from 33,000 flight cycles to 25,000 flight cycles.
    (2) Amend any other Reference, where the maximum approved life 
limit is quoted for the LP compressor (fan) disc assembly P/N 
BRH10048 or LP compressor (fan) disc assembly P/N BRH19253, when 
installed in the BR700-715A-30 engine model and operated under the 
Hawaiian Flight Mission, to the revised maximum approved life limit 
of 25,000 flight cycles.

BR700-715B1-30 and BR700-715C1-30 Turbofan Engines

    (3) For BR700-715B1-30 and BR700-715C1-30 turbofan engines:
    (i) Check to see if the LP compressor (fan) disc assembly P/N 
BRH10048 or LP compressor (fan) disc assembly P/N BRH19253 is 
currently, or has previously been, installed in the BR700-715A1-30 
engine model and operated under the Hawaiian Flight Mission, by 
checking the Life Limited Parts (LLP) Tracking Sheet. Information on 
recording and control of the lives of the parts can be found in the 
Airworthiness Limitations Section of the Time Limits Manual TASK 05-
00-01-800-001.
    (ii) If the LP compressor (fan) disc assembly has not operated, 
and is not going to operate in the Hawaiian Flight Mission, no 
further action is required.
    (iii) If the LP compressor (fan) disc assembly has operated in 
the Hawaiian Flight Mission:
    (A) Apply the prorate calculations and complete the LLP Tracking 
Sheet using the revised Hawaiian Flight Mission maximum approved 
life limit of 25,000 flight cycles.
    (B) Remove LP compressor (fan) disc assemblies from service 
before reaching 25,000 flight cycles.

Other FAA AD Provisions

    (f) Alternative Methods of Compliance: The Manager, Engine 
Certification Office, FAA, 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

    (g) Refer to MCAI European Aviation Safety Agency Airworthiness 
Directive 2007-0116-E, dated May 4, 2007, for related information.
    (h) Contact Jason Yang, Aerospace Engineer, Engine Certification 
Office, FAA, Engine and Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: Jason.yang@faa.gov; 
telephone (781) 238-7747; fax (781) 238-7199, for more information 
about this AD.

    Issued in Burlington, Massachusetts, on January 28, 2008.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E8-2039 Filed 2-4-08; 8:45 am]

BILLING CODE 4910-13-P
