[Federal Register Volume 69, Number 191 (Monday, October 4, 2004)]
[Proposed Rules]
[Pages 59148-59151]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-22192]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19157; Directorate Identifier 2004-NE-30-AD]
RIN 2120-AA64
Airworthiness Directives; Rolls-Royce Deutschland (RRD) (Formerly
Rolls-Royce plc) Tay 650-15 Series Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain RRD Tay 650-15 series turbofan engines. This proposed AD
would require inspection of the high pressure compressor (HPC) shaft
and high pressure turbine (HPT) shaft for spline flank wear. This
proposed AD results from a number of occurrences of excessive HPC shaft
and HPT shaft
[[Page 59149]]
spline flank wear discovered during on-wing and in-shop inspections. We
are proposing this AD to prevent spline disengagement resulting in an
overspeed event, which could lead to an uncontained engine failure and
possible damage to the airplane.
DATES: We must receive any comments on this proposed AD by December 3,
2004.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401,
Washington, DC 20590-001.
Fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
You can get the service information identified in this proposed AD
from Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, D-15827
Dahlewitz, Germany; telephone 49 (0) 33-7086-1768; fax 49 (0) 33-7086-
3356.
You may examine the comments on this proposed AD in the AD docket
on the Internet at http://dms.dot.gov.
FOR FURTHER INFORMATION CONTACT: Ian Dargin, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7178; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION:
Docket Management System (DMS)
We have implemented new procedures for maintaining AD dockets
electronically. As of May 17, 2004, we post new AD actions on the DMS
and assign a DMS docket number. We track each action and assign a
corresponding Directorate identifier. The DMS docket No. is in the form
``Docket No. FAA-200X-XXXXX.'' Each DMS docket also lists the
Directorate identifier (``Old Docket Number'') as a cross-reference for
searching purposes.
Comments Invited
We invite you to submit any written relevant data, views, or
arguments regarding this proposal. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2004-19157;
Directorate Identifier 2004-NE-30-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://dms.dot.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
DMS Web site, anyone can find and read the comments in any of our
dockets, including 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) or you
may visit http://dms.dot.gov.
We are reviewing the writing style we currently use in regulatory
documents. We are interested in your comments on whether the style of
this document is clear, and your suggestions to improve the clarity of
our communications that affect you. You can get more information about
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.
Examining the AD Docket
You may examine the docket that contains the proposal, any comments
received, and any final disposition in person at the DMS Docket Offices
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The Docket Office (telephone (800) 647-5227) is located on
the plaza level of the Department of Transportation Nassif Building at
the street address stated in ADDRESSES. Comments will be available in
the AD docket shortly after the DMS receives them.
Discussion
The Civil Aviation Authority (CAA), which is the airworthiness
authority for the United Kingdom, recently notified us that an unsafe
condition might exist on certain RRD Tay 650-15 series turbofan
engines. The CAA advises that the spline flanks on the HPC shaft and
HPT shaft may be developing excessive wear. The amount of wear is
directly related to the amount of relative movement between the HPC and
an immobilized HPT. You can detect wear by inspecting the engine to
determine the amount of relative movement between the HPC and an
immobilized HPT. On-wing and in-shop inspections found excessive spline
flank wear on HPC shafts and HPT shafts that incorporated Service
Bulletin (SB) No. TAY-72-1327 (hard coated abutment face) and HPC
shafts and HPT shafts that did not incorporate SB No. TAY-72-1327.
Relevant Service Information
We have reviewed and approved the technical contents of RRD SB No.
TAY-72-1485, Revision 2, dated March 21, 2003 that describes procedures
for inspecting the flanks on the HPC shaft and HPT shaft for wear. The
CAA classified the initial Rolls-Royce plc (RR) SB as mandatory and
issued airworthiness directive CAA 001-01-2002, dated January 11, 2002
in order to ensure the airworthiness of these RR engines in the United
Kingdom. Subsequently, the certification responsibility was transferred
to RRD and Revision 1 and Revision 2 were reclassified to
``Recommended'' by the Luftfahrt-Bundesamt (LBA), which is the aviation
authority for Germany.
Differences Between This Proposed AD and the Manufacturer's Service
Information
The RRD SB No. TAY-72-1485, Revision 2, dated March 21, 2003
specifies compliance times based on the date of receipt of the SB. We
have mandated compliance times based on the effective date of this
proposed AD.
At initial inspection, if the HPC shaft or HPT shaft has
accumulated 3,000 flight cycles or more, RRD SB No. TAY-72-1485, dated
January 11, 2002, specifies compliance within 12 months. At initial
inspection, if the HPC shaft or HPT shaft has accumulated 3,000 flight
cycles or more, we specify compliance within six months from the
effective date of the final rule.
FAA's Determination and Requirements of the Proposed AD
This engine model, manufactured in Germany, is type-certificated
for operation in the United States under the provisions of section
21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the
applicable bilateral airworthiness agreement. In keeping with this
bilateral airworthiness agreement, the CAA and LBA have kept us
informed of the situation described above. We have examined the
findings of the CAA and LBA, reviewed all available information, and
determined that AD action is necessary for products
[[Page 59150]]
of this type design that are certificated for operation in the United
States. We are proposing this AD, which would require inspecting the
spline flanks on the HPC shaft and HPT shaft for wear. The proposed AD
would require you to use the service information described previously
to perform these actions.
Costs of Compliance
There are about 390 RRD Tay 650-15 series turbofan engines of the
affected design in the worldwide fleet. We estimate that 172 engines
installed on airplanes of U.S. registry would be affected by this
proposed AD. We also estimate that it would take about 4 work hours per
engine to perform the proposed actions, and that the average labor rate
is $65 per work hour. Based on these figures, we estimate the total
cost of the proposed AD to U.S. operators, per inspection cycle, to be
$44,720. We also estimate, for the HPC shaft of 172 engines to be
replaced at teardown, with a parts cost of approximately $13,862 per
shaft, the total cost of the proposed AD to U.S. operators to be
$2,384,264.
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 summary of the costs to comply with this proposal 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.
The Proposed Amendment
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 Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding a new airworthiness directive (AD) to read as follows:
Roll-Royce Deutschland Ltd & Co KG (RRD) (Formerly Rolls-Royce plc):
Docket No. FAA-2004-19157; Directorate Identifier 2004-NE-30-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by December
3, 2004.
Affected ADs
(b) None.
Applicability
(c) This AD applies to RRD Tay 650-15 series turbofan engines.
These engines are installed on, but not limited to, Fokker F100
airplanes.
Unsafe Condition
(d) This AD results from a number of occurrences of excessive
high pressure compressor (HPC) and high pressure turbine (HPT) shaft
spline wear and spline flank wear discovered during on-wing and in-
shop inspections. We are issuing this AD to prevent spline
disengagement resulting in an overspeed event, which could lead to
an uncontained engine failure and possible 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.
Initial Visual Inspection of the HPC Shaft and HPT Shaft Splines
(f) Within the compliance times specified in Table 1 of this AD,
perform initial inspections of the HPC shaft splines and HPT shaft
splines of RRD Tay 650-15 series turbofan engines. Use paragraph
3.A. of Accomplishment Instructions of RRD Service Bulletin (SB) No.
TAY-72-1485, Revision 2, dated March 21, 2003, to do the
inspections. Calculate spline wear using Appendix 1, paragraph 4.K.,
of RRD SB No. TAY-72-1485, Revision 2, dated March 21, 2003.
Table 1.--HPC Shaft Splines and HPT Shaft Splines Inspection Schedule
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Current shaft life Action
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(1) If the HPC shaft or HPT shaft has Inspect HPC shaft splines and
accumulated 3,000 cycles-since-new HPT shaft splines for wear
(CSN) or more on the effective date of within six months after the
this AD. effective date of this AD,
unless previously done.
(2) If the HPC shaft or HPT shaft has Wait until the HPC shaft or HPT
accumulated fewer than 3,000 CSN on shaft has accumulated 3,000
the effective date of this AD. flight cycles, then inspect
the HPC shaft splines and HPT
shaft splines for wear within
300 cycles-since-last visual
inspection (CSLI) or remainder
of 12 months from the
effective date of this AD,
whichever is greater.
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(g) Disposition the HPC shaft, HPT shaft, or engine as specified
in Table 2 of this AD.
Table 2.--Visual Inspection Criteria
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Inspection limits Disposition
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(1) If spline wear is 0.1 inch or Remove engine from service
greater. within 50 cycles-since-last
visual inspection CSLI).
(2) If spline wear is greater than or Remove engine from service
equal to 0.06 inch but less than 0.1 within 500 CSLI.
inch.
(3) If spline wear is greater than or Inspect HPC shaft and HPT shaft
equal to 0.03 inch but less than 0.06 using the intervals in
inch.. paragraph (h)(1) of this AD.
[[Page 59151]]
(4) If spline wear is less than 0.03 Inspect HPC shaft and HPT shaft
inch. using the intervals in
paragraph (h)(2) of this AD.
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Repetitive Visual Inspection of the HPC Shaft and HPT Shaft Splines
(h) Perform repetitive inspections of the HPC shaft splines and
HPT shaft splines of RRD Tay 650-15 series turbofan engines. Use
paragraph 3.A. of Accomplishment Instructions with Appendix 1 of RRD
SB No. TAY-72-1485, Revision 2, dated March 21, 2003, to do the
inspections. Calculate spline wear using Appendix 1, paragraph 4.K.,
of RRD SB No. TAY-72-1485, Revision 2, dated March 21, 2003.
(1) If wear measured in paragraph (f) of this AD was greater
than or equal to 0.03 inch but less than 0.06 inch, repetitively
inspect HPC shaft and HPT shaft within 1,000 cycles-since-last
visual inspection (CSLI).
(2) If wear measured in paragraph (f) of this AD was less than
0.03 inch, repetitively inspect HPC shaft and HPT shaft within 5,500
CSLI.
(i) Disposition the HPC shaft, HPT shaft, or engine as specified
in Table 2 of this AD.
Previous Credit
(j) Previous credit is allowed for performing the initial
inspections in paragraph (f) of this AD, that were done using the
Accomplishment Instructions of one of the following, before the
effective date of this AD:
(1) SB No. TAY-72-1485, dated January 11, 2002;
(2) SB No. TAY-72-1485, Revision 1, dated January 29, 2003; and
(3) SB No. TAY-72-1485, Revision 2, dated March 21, 2003.
Material Incorporated by Reference
(k) None.
Related Information
(l) Civil Aviation Authority (CAA) airworthiness directive 001-
01-2002, dated January 11, 2002, also addresses the subject of this
AD.
Issued in Burlington, Massachusetts, on September 24, 2004.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 04-22192 Filed 10-1-04; 8:45 am]
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