
[Federal Register: May 21, 2008 (Volume 73, Number 99)]
[Rules and Regulations]               
[Page 29405-29407]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21my08-4]                         

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0037; Directorate Identifier 2007-NE-41-AD; 
Amendment 39-15521; AD 2008-10-14]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce Deutschland Ltd. & Co. KG. 
(RRD) TAY 650-15 Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) issued by an aviation authority of 
another country to identify and correct an unsafe condition on an 
aviation product. The MCAI describes the unsafe condition as:

    Strip results from some of the engines listed in the 
applicability section of this directive revealed excessively 
corroded low pressure turbine disks stage 2 and stage 3. The 
corrosion is considered to be caused by the environment in which 
these engines are operated. Following a life assessment based on the 
strip findings it is concluded that inspections for corrosion attack 
are required. The action specified by this AD is intended to avoid a 
failure of a low pressure turbine disk stage 2 or stage 3 due to 
potential corrosion problems which could result in uncontained 
engine failure and damage to the airplane.

We are issuing this AD to detect corrosion that could cause stage 2 or 
stage 3 disk of the low pressure turbine to fail and result in an 
uncontained failure of the engine.

DATES: This AD becomes effective June 25, 2008. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in this AD as of June 25, 2008.

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: Jason Yang, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & 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:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on January 2, 2008 (73 
FR 75). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states that:

    Strip results from some of the engines listed in the 
applicability section of this directive revealed excessively 
corroded low pressure turbine disks stage 2 and stage 3. The 
corrosion is considered to be caused by the environment in which 
these engines are operated. Following a life assessment based on the 
strip findings it is concluded that inspections for corrosion attack 
are required.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We received no comments on the NPRM or on the determination of 
the cost to the public.

Editorial Change To Clarify the Actions and Compliance Section

    We added the revision date of September 1, 2006, to paragraph 
(e)(1) to clarify the requirements to that paragraph. Also, we added 
Tasks 72-52-23-200-000 and 72-52-24-200-000 to paragraph (e)(3) to 
clarify the requirements of that paragraph.

Conclusion

    We reviewed the available data and determined that air safety and 
the public interest require adopting the AD with the changes described 
previously. We determined that these changes will not increase the 
economic burden on any operator or increase the scope of the AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about two engines installed on airplanes of U.S. registry. 
We also estimate that it would take about 1.0 work-hours per product to 
inspect the disk, and that the average labor rate is $80 per work-hour. 
If corrosion is found, we estimate that it would take about 2 work-
hours to replace the disk. Required parts would cost about $40,000 per 
product. Based on these

[[Page 29406]]

figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $80,480. Our cost estimate is exclusive of possible 
warranty coverage.

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 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 this 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. 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 AD and placed it in the AD docket.

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.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA 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 AD:

2008-10-14 Rolls-Royce Deutschland Ltd & Co KG (RRD) (formerly 
Rolls-Royce plc, Derby, England): Amendment 39-15521. FAA-2007-0037; 
Directorate Identifier 2007-NE-41-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective June 25, 
2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to RRD TAY 650-15 turbofan engines that have 
a serial number listed in Table 1 of this AD, and low pressure 
turbine module M05300AA installed. These engines are installed on, 
but not limited to, Fokker F28 Mark 0100 airplanes.

         Table 1.--Affected TAY 650-15 Engines by Serial Number
------------------------------------------------------------------------
                            Engine Serial No.
-------------------------------------------------------------------------
17251
17255
17256
17273
17275
17280
17281
17282
17300
17301
17327
17332
17365
17393
17437
17443
17470
17520
17521
17523
17539
17542
17556
17561
17562
17563
17580
17581
17612
17618
17635
17637
17645
17661
17686
17699
17701
17702
17736
17737
17738
17739
17741
17742
17808
------------------------------------------------------------------------

Reason

    (d) Strip results from some of the engines listed in the 
applicability section of this directive revealed excessively 
corroded low pressure turbine disks stage 2 and stage 3. The 
corrosion is considered to be caused by the environment in which 
these engines are operated. Following a life assessment based on the 
strip findings it is concluded that inspections for corrosion attack 
are required. The action specified by this AD is intended to avoid a 
failure of a low pressure turbine disk stage 2 or stage 3 due to 
potential corrosion problems which could result in uncontained 
engine failure and damage to the airplane.

    We are issuing this AD to detect corrosion that could cause 
stage 2 or stage 3 disk of the low pressure turbine to fail and 
result in an uncontained failure of the engine.

Actions and Compliance

    (e) Unless already done, do the following actions.
    (1) Prior to accumulating 11,700 flight cycles (FC) since new, 
and thereafter at intervals not exceeding 11,700 FC of the engine, 
inspect the low pressure turbine disks stage 2 and stage 3 for 
corrosion in accordance with RRD Alert Service Bulletin TAY-72-
A1524, Revision 1, dated September 1, 2006.

    (2) For engines that already exceed 11,700 FC on the effective 
date of this AD, perform the inspection within 90 days after the 
effective date of this AD.

    (3) When, during any of the inspections as required by paragraph 
(e)(1) of this directive, corrosion is found, replace the affected 
parts. The RRD TAY 650 Engine Manual--E-TAY-3RR, Tasks 72-52-23-200-
000 and 72-52-24-200-000 contains information on performing the 
inspection for corrosion and rejection criteria.

[[Page 29407]]

Other FAA AD Provisions

    (f) Alternative Methods of Compliance (AMOCs): The Manager, 
Engine Certification Office, FAA, has the authority to approve AMOCs 
for this AD, if requested using the procedures found in 14 CFR 
39.19.

Related Information

    (g) Refer to EASA Airworthiness Directive 2006-0288, dated 
September 15, 2006, and RRD Alert Service Bulletin TAY-72-A1524, 
Revision 1, dated September 1, 2006, for related information.
    (h) Contact Jason Yang, Aerospace Engineer, Engine Certification 
Office, FAA, Engine & 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.

Material Incorporated by Reference

    (i) You must use Rolls-Royce Deutschland Alert Service Bulletin 
TAY-72-A1524, Revision 1, dated September 1, 2006, to do the actions 
required by this AD, unless the AD specifies otherwise.
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (2) For service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlwitz, 15827 
Blankenfelde-Mahlow, Germany; telephone 49 (0) 33-7086-1768; fax 49 
(0) 33-7086-3356.
    (3) You may review copies at the FAA, New England Region, 12 New 
England Executive Park, Burlington, MA; or at the National Archives 
and Records Administration (NARA). For information on the 
availability of this material at NARA, call (202) 741-6030, or go 
to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Burlington, Massachusetts, on May 5, 2008.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E8-10633 Filed 5-20-08; 8:45 am]

BILLING CODE 4910-13-P
