Document ID: FAA-2011-0836-0006
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Rolls-Royce plc (RR) RB211-Trent 800 Series Turbofan Engines
Posted Date: 2011-12-20T05:00Z

[Federal Register Volume 76, Number 244 (Tuesday, December 20, 2011)]
[Rules and Regulations]
[Pages 78805-78808]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-32490]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0836; Directorate Identifier 2010-NE-38-AD; 
Amendment 39-16898; AD 2011-26-08]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce plc (RR) RB211-Trent 800 
Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all 
Rolls-Royce plc (RR) RB211-Trent 800 Series Turbofan Engines. This AD 
results from mandatory continuing airworthiness information (MCAI) 
originated 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 fuel leaks from the engine due to damage to 
sections of the fan case low-pressure (LP) fuel tubes. We are issuing 
this AD to prevent engine fuel leaks, which could result in risk to the 
airplane.

DATES: This AD becomes effective January 24, 2012. The Director of the 
Federal Register approved the

[[Page 78806]]

incorporation by reference of certain publications listed in this AD as 
of January 24, 2012.

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: Alan Strom, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; email: 
alan.strom@faa.gov; phone: (781) 238-7143; 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 August 22, 2011 (76 
FR 52288). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    Fuel leaks from the engine have occurred in-service due to 
damage to sections of the fan case Low Pressure (LP) fuel tubes 
which run between the Low Pressure and the High Pressure (HP) fuel 
pumps. This damage has been caused by frettage between the securing 
clips and the tube outer surface, which has caused localised 
thinning of the tube wall thickness. The thinning of the tube wall 
causes the tube to fracture and fuel loss to occur.

    The corrective action includes inspection of the tubes and 
replacement of the associated clips. The fretting and thinning of the 
fuel tubes is caused by relative movement between the tubes and the 
clips. You may obtain further information by examining the MCAI in the 
AD docket.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received.

Request To Correct Title in Rolls-Royce Service Bulletin

    A commenter, Air New Zealand, requested that we change the service 
bulletin reference from ``RB.211-73-D685'' to ``RB.211-73-AD685.''
    We agree. The changed the AD to correct the service bulletin 
reference.

Request To Change Service Bulletin Revision Number

    Three commenters, American Airlines (American), Delta Airlines 
(Delta), and the Boeing Company (Boeing), suggested that we change 
compliance from Revision 5 to Revision 6 of the Rolls-Royce Service 
Bulletin.
    We agree. We changed the AD to use RR SB RB.211-73-AD685, Revision 
6, dated February 21, 2011, which is the latest version of the service 
bulletin.

Request To Allow Compliance to Earlier Revisions of the Service 
Bulletin

    One commenter, Delta, asked that engines previously inspected per 
Revision 3 of SB RB.211-73-AD685, dated August 18, 2009; or Revision 4 
of SB RB.211-73-AD685, dated January 20, 2010 or Revision 5 of SB 
RB.211-73-AD685, dated August 18, 2010; to have met the initial 
inspection requirements of the AD.
    We agree. We added a new paragraph to the AD called ``Previous 
Inspection Credit'' which provides credit for performing the initial 
inspection according to the requirements of Revisions 3, 4, or 5 of the 
SB.

Request To Revise Cost of Compliance

    A commenter, American Airlines, requested that the cost estimate 
per engine be increased to $905. American noted that the AD creates 
repetitive not one-time expenses due to the need for repetitive 
inspections. American also asserted that the estimate in the NPRM (76 
FR 52288, August 22, 2011) of labor hours to comply with the AD was not 
accurate. American suggested 8 labor hours per inspection is a 
realistic figure.
    We agree in part. While the AD does require repetitive inspections, 
we do not agree with including repetitive expenses for inspections in 
our cost estimate. We only include the cost of one inspection cycle, 
even if the AD requires repetitive inspections, in our cost estimates. 
We agree our labor estimate should be increased. We accept that 8 labor 
hours is a realistic estimate of labor hours and allows us to make a 
more accurate assessment of labor cost. We changed the estimate of work 
hours in the AD from 3 to 8. We also corrected the cost of the parts 
required from $225 in the NPRM to $884. We revised the total cost to 
comply with the AD from $52,800 to $172,040.

Request To Revise Initial Inspection Paragraph

    A commenter, Boeing, requested that the Initial Inspection 
paragraph be revised by including the following: ``Inspect the Fuel Oil 
Heat Exchanged (FOHE) mounting hardware for signs of damage. Use 
paragraph 3.A.(4) of the Service Bulletin RB.211-73-AD685, Revision 6, 
dated February 21, 2011.'' Boeing noted that damage or wear to FOHE 
mounts may contribute to low pressure (LP) fuel tube cracking. Delta 
Airlines commented further that EASA AD 2010-0188 requires this FOHE 
mount inspection because it requires accomplishment of the entire 
service bulletin when doing the inspection. For clarity, Delta 
requested that the final rule include a comment that the inspection 
requirements do not mandate the FOHE mount inspections.
    We do not agree. The requirement of this AD to inspect the fuel 
tubes is sufficient to ensure safe operation. The repetitive inspection 
intervals for fuel tubes required by this AD consider observed FOHE 
mount wear. This AD does not require inspection of the FOHE mounts. We 
did not change the AD based on this comment.

Request To Add Requirement To Remove Damaged Fuel Tubes

    Two commenters, Boeing and Delta, requested clarification regarding 
when to replace fuel tubes. Boeing requested that under ``Actions and 
Compliance'' the following requirement be included: ``Removal and 
replacement of damaged fuel tubes (P/N FK23986) in accordance with 
paragraph 3.A.(5) of the Service Bulletin RB.211-73-AD685, Revision 6, 
dated February 21, 2011.'' Boeing indicated that rejected fuel tubes 
need to be replaced to avoid fuel leaks. Delta indicated that the On-
wing Inspection and In-shop Inspection paragraphs do not include 
information about replacing tubes when needed as the result of 
inspections. Delta also noted that the Repetitive Inspection paragraph 
does discuss replacement of these parts when needed.
    We agree in part. Although parts that fail inspection may not be 
returned to service, we agree that clarifying when fuel tubes are 
replaced would help. We revised the On-wing Inspection and In-shop 
Inspection paragraphs to indicate that the tubes should be replaced if 
they fail inspection.

Request To Clarify Initial Inspection Requirement

    One commenter, Delta, noted that under the Initial Inspection 
paragraph, one of the options for complying with the AD is to do the 
initial inspection before 3,000 hours since last inspection. Delta 
requested that we clarify the meaning of ``last inspection.''
    We agree. We added a definition paragraph to indicate that our 
reference to 3,000 hours since last inspection refers to the inspection 
of the fan case LP fuel tubes for frettage between the securing clips 
and the tube outer surface part numbers FK22617, FK19213, and FK23986.

[[Page 78807]]

Request To Clarify Handling of Clips for Fuel Tubes

    One commenter, Delta, asked that the final rule clarify how to 
handle the clips that hold the fuel tubes in place. Delta noted that 
paragraphs 3.A.(2) and 3.A.(3) (on-wing) and 3.B.(2) and 3.B.(3) of RR 
SB RB.211-73-AD685, which are referenced in the NPRM (76 FR 52288), do 
not include inspection criteria for the clips. Delta requested that we 
either require inspection or replacement of the clips with a new or 
serviceable part per the note in Paragraph 3.A. of the RR SB RB.211-73-
AD685, which says that ``clips should be removed and replaced one at a 
time to prevent pre-loading of the clip position.''
    We agree. The fretting and thinning of the fuel tubes is caused by 
relative movement between the tubes and the clips. Worn or fretted 
clips cause increased relative movement between the tubes and the clips 
and thus more tube wear and fretting. Clip wear is not repairable and 
so the clips cannot be reused. We, therefore, revised the AD by 
changing the On-wing Inspection and In-shop Inspection paragraphs to 
indicate that the clips must be replaced during the initial inspection 
and during every repeat inspection.

Request To Clarify Repeat Inspections Paragraph

    One commenter, Delta, requested clarification of the Repeat 
Inspections paragraph. Delta noted that this paragraph might be 
misinterpreted to mean inspection and tube replacement should be 
accomplished per paragraphs 3.A.(2), 3.A.(3), 3.B.(2), and 3.B.(3) of 
RR SB RB.211-73-AD685. Since these paragraphs only apply to replacement 
of the tubes, Delta believes the language should be clarified.
    We agree. We revised the Repeat Inspections paragraph to clarify 
that paragraphs 3.A.(1) through 3.A.(3) (On-wing) or 3.B.(1) through 
3.B.(3) (In-shop) of RR SB RB.211-78-AD685 apply to the inspection.

Conclusion

    We 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 determined that these 
changes will not increase the economic burden on any operator nor 
increase the scope of the AD.

Costs of Compliance

    We estimate that this AD affects about 110 products of U.S. 
registry. We also estimate that it will take about 8 work-hours per 
product to comply with this AD. The average labor rate is $85 per work-
hour. Required parts cost about $884 per product. Based on these 
figures, we estimate the cost of the AD on U.S. operators to be 
$172,040.

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 (phone: (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

    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 airworthiness 
directive (AD):

2011-26-08 Rolls-Royce plc: Amendment 39-16898; Docket No. FAA-2011-
0836; Directorate Identifier 2010-NE-38-AD.

(a) Effective Date

    This airworthiness directive (AD) becomes effective January 24, 
2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Rolls-Royce plc (RR) RB211-Trent 875-17, 
877-17, 884-17, 884B-17, 892-17, 892B-17, and 895-17 turbofan 
engines. These engines are installed on, but not limited to, Boeing 
777 series airplanes.

(d) Reason

    This AD was prompted by fuel leaks from the engine that occurred 
in-service due to damage to sections of the fan case low-pressure 
(LP) fuel tubes, which run between the LP and the high-pressure (HP) 
fuel pumps. This damage was caused by frettage between the securing 
clips and the tube outer surface, which caused localized thinning of 
the tube wall thickness. The thinning of the tube wall causes the 
tube to fracture and leak fuel. We are issuing this AD to prevent 
engine fuel leaks, which could result in risk to the airplane.

(e) Actions and Compliance

    Unless already done, do the following actions.

(f) Initial Inspection and Clip replacement

    Within 2,000 hours in service after the effective date of this 
AD, or before accumulating 3,000 hours-since-new or 3,000 hours-
since-last-inspection, whichever is latest, do one of the following:

(1) On-Wing Inspection and Clip Replacement

    Inspect the fan case LP fuel tubes, part numbers (P/Ns) FK22617, 
FK19213, and

[[Page 78808]]

FK23986. Replace the clips that hold the fuel tubes in place. Use 
paragraphs 3.A.(1) through 3.A.(3) (on-wing) of RR Non-modification 
Alert Service Bulletin (ASB) RB.211-73-AD685, Revision 6, dated 
February 21, 2011 to do the inspection. Replace any fan case LP fuel 
tubes that fail inspection.

(2) In-Shop Inspection and Clip Replacement

    Inspect the fan case LP fuel tubes, P/N FK22617, FK19213, and 
FK23986. Replace the clips that hold the fuel tubes in place with 
new or serviceable clips. Use paragraphs 3.B.(1) through 3.B.(3) 
(in-shop) of RR Non-modification ASB RB.211-73-AD685, Revision 6, 
dated February 21, 2011 to do the inspection. Replace any fan case 
LP fuel tubes that fail inspection.

(g) Repetitive Inspection and Clip Replacement

    Repeat the inspection required by paragraphs (f)(1) and (f)(2) 
of this AD and replace the clips at intervals not exceeding every 
3,000 hours time-since-last-inspection.

(h) Re-Installation Prohibition

    Do not re-install any clips replaced in accordance with 
paragraphs (f)(1) and (f)(2) of this AD.

(i) Previous Inspection Credit

    If you previously performed the inspection required by Revision 
3 of SB RB.211-73-D685, dated August 18, 2009, or Revision 4 of SB 
RB.211-73-D685, dated January 20, 2010, or Revision 5 of ASB RB.211-
73-AD685, dated August 18, 2010, you met the initial inspection 
requirements of this AD.

(j) Definition

    ``Last inspection'' means the last inspection of the fan case LP 
fuel tubes, P/Ns FK22617, FK19213, and FK23986, for frettage between 
the securing clips and the tube outer surface.

(k) FAA AD Differences

    None.

(l) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
for this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(m) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
European Aviation Safety Agency (EASA) Airworthiness Directive 2010-
0188, dated September 20, 2010, and Rolls-Royce plc Alert Service 
Bulletin RB.211-73-AD685, Revision 6, dated February 21, 2011, for 
related information. Contact Rolls-Royce plc, Corporate 
Communications, P.O. Box 31, Derby, England, DE248BJ; phone: 011-44-
1332-242424; fax: 011-44-1332-245418; or email: http://www.rolls-royce.com/contact/civil_team.jsp, for a copy of this service 
information.
    (2) Contact Alan Strom, Aerospace Engineer, Engine Certification 
Office, FAA, Engine & Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; email: alan.strom@faa.gov; 
phone: (781) 238-7143; fax: (781) 238-7199, for more information 
about this AD.

(n) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the 
following service information on the date specified.
    (2) Rolls-Royce plc Alert Service Bulletin RB.211-73-AD685, 
Revision 6, dated February 21, 2011, approved for IBR January 24, 
2012.
    (3) For service information identified in this AD, contact 
Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, 
England, DE248BJ; phone: 011-44-1332-242424; fax: 011-44-1332-245418 
or email: http://www.rolls-royce.com/contact/civil_team.jsp.
    (4) You may review copies at the FAA, New England Region, 12 New 
England Executive Park, Burlington, MA. For information on the 
availability of this material at the FAA, call (781) 238-7125.
    (5) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at an NARA facility, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Burlington, Massachusetts, on December 12, 2011.
Thomas A. Boudreau,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-32490 Filed 12-19-11; 8:45 am]
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