Document ID: FAA-2010-0993-0009
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Rolls-Royce plc RB211-524 Series, RB211-Trent 700 Series, and RB211-Trent 800 Series Turbofan Engines
Posted Date: 2011-10-25T04:00Z

[Federal Register: October 25, 2011 (Volume 76, Number 206)]
[Rules and Regulations]               
[Page 65941-65944]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr25oc11-6]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0993; Directorate Identifier 2010-NE-08-AD; 
Amendment 39-16849; AD 2011-22-07]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce plc RB211-524 Series, 
RB211-Trent 700 Series, and 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 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:

    Cracking has been found on the inner wall between intermediate 
dilution chutes on a total of five front combustion liners of the 
standard corresponding to Rolls-Royce RB211 Service Bulletin No. 72-
D133. The lives of two of these liners were confirmed to be below 
the currently valid borescope inspection interval. Ultimately, crack 
propagation could result in hot gas breakout with potential of 
downstream component distress and multiple turbine blade release 
beyond containment capabilities of the engine casings. Thus, 
cracking of this nature constitutes a potentially unsafe condition.
    Since Rolls-Royce Service Bulletin No. 72-E902 introduces 
further developments of Rolls-Royce RB211 Service Bulletin No. 72-
D133, engines incorporating Rolls-Royce RB211 Service Bulletin No. 
72-E902 are also considered to be potentially affected and are 
therefore included in the applicability of this AD.

We are issuing this AD to detect cracks in the front combustion liner, 
which could result in hot section distress, multiple blade release, and 
possible damage to the airplane.

DATES: This AD becomes effective November 29, 2011. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in this AD as of November 29, 2011.

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; e-mail: 
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 October 5, 2010 (75 
FR 61363). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states that:

    Cracking has been found on the inner wall between intermediate 
dilution chutes on a total of five front combustion liners of the 
standard corresponding to Rolls-Royce RB211 Service Bulletin No. 72-
D133. The lives of two of these liners were confirmed to be below 
the currently valid borescope inspection interval. Ultimately, crack 
propagation could result in hot gas breakout with potential of 
downstream component distress and multiple turbine blade release 
beyond containment capabilities of the engine casings. Thus, 
cracking of this nature constitutes a potentially unsafe condition.
    Since Rolls-Royce Service Bulletin No. 72-E902 introduces 
further developments of Rolls-Royce RB211 Service Bulletin No. 72-
D133, engines incorporating Rolls-Royce RB211 Service Bulletin No. 
72-E902 are also considered to be potentially affected and are 
therefore included in the applicability of this AD.
    This AD requires a change to the initial and repeat borescope 
inspection intervals for the front combustion liner.

Comments

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

Request To Expand Address for Service Information

    One commenter, Rolls-Royce plc (RR), asked us to consider changing 
the information for getting the service information to ``For any 
questions concerning the technical content of the requirements in this 
AD (NPRM), please contact your designated Rolls-Royce representative 
for a copy of the service information, please download the publication 
from your Aeromanager account at http://www.aeromanager.com. If you do 
not have a designated representative or an Aeromanager account, please 
contact Corporate Communications at Rolls-Royce plc, PO Box 31, Derby, 
DE24 8BJ, United Kingdom, phone: 011-44-1331-242424, fax: 011-44-1332-
249936, or e-mail: http://www.rolls-royce.com/contact/civil_team.jsp 
identifying the correspondence as being related to Airworthiness 
Directives.'' RR states that this should make sure that any questions 
from operators of their engines and those from other parties are 
directed to the area best equipped to answer.
    We partially agree. We agree that operators and maintenance 
providers need to get timely and accurate service information, and that 
additional information is worth including. We changed paragraph (k) of 
the AD to state ``* * * contact Corporate Communications at Rolls-Royce 
plc PO Box 31, Derby, DE24 8BJ, United Kingdom, Phone: 011-44-1331-
242424, fax 011-44-1332-249936 or e-mail from http://www.rolls-
royce.com/contact/civil_team.jsp identifying the correspondence as 
being related to Airworthiness Directives.''
    We do not agree that operators or maintenance providers should 
contact RR for questions about this AD. We did not include that 
information in the AD.

Requests To Change References to the Service Bulletin That Is 
Incorporated by Reference

    Two commenters, American Airlines (AA) and The Boeing Company 
(Boeing), asked us to add ``or later

[[Page 65942]]

revision'' after ``Service Bulletin No. RB.211-72-AF458, Revision 2, 
dated December 21, 2007.'' Boeing stated the latest revision of Service 
Bulletin (SB) No. RB.211-72-AF458 is Revision 4. Boeing stated that 
airlines have been inspecting their combustion liners to Revision 4 of 
the SB and the compliance intervals specified in the NPRM are 
consistent with RR SB RB.211-72-AF458, Revision 4 and EASA AD 2009-
0243R1. AA stated the borescope inspection is the same on later 
revisions, so the life should be counted from the latest SB revision.
    We do not agree. On review of the SB, we determined that the 
inspection requirements and limits called out in the SB are already in 
the engine and aircraft maintenance manuals. We changed the AD to 
remove the incorporation by reference of the SB.
    One commenter, AA, asked us to revise paragraph (f) of the AD to 
specifically call out which paragraphs of SB RB.211-72-AF458 are 
incorporated by reference. AA stated the NPRM called out all of section 
3 of the SB, which is too prescriptive given the nature of the 
inspections.
    We do not agree. On review of the SB, we found incorporation by 
reference unnecessary. We changed the AD to remove the incorporation by 
reference of the SB.

Request To Remove an Engine Model From the Applicability

    One commenter, AA, asked us to remove the RR RB211-535 engine model 
from the applicability of the proposed AD. AA stated they have recorded 
no crack findings against the RB211-535 model.
    We agree. The thermal, acoustical, and vibratory stress environment 
of the RB211-535 combustion liner is different from that of the other 
engines to which this AD applies. We removed the RB211-535E4-37, RB211-
535E4-B-37, RB211-535E4-C-37, and RB211-535E4-B-75 from the 
Applicability paragraph (c) of this AD, and updated our cost estimate 
to reflect the fewer affected engines.

Request To Change the Number of Cracking Events

    One commenter, Boeing, asked us to change paragraph (d) of the 
proposed AD to specify that six cracking events have been found instead 
of five. Boeing states that changing paragraph (d) of the proposed AD 
will more accurately reflect the need for the inspections.
    We agree. Although an additional cracking event has occurred, the 
AD was prompted by the investigation of five events. We changed 
paragraph (d) of this AD to reflect six known cracking events.

Request To Add a Grace Period for Compliance

    One commenter, Boeing asked us to change paragraphs (f)(1)(i) and 
(f)(1)(iii) of the proposed AD to add ``within 15 cycles of the date of 
issue of the AD'' before the word ``or.'' Boeing states that adding the 
15 cycle grace period will give operators time to get back to base for 
the inspection.
    We partially agree. No additional grace period is required. This AD 
does not require inspecting any engine earlier than 250 cycles after 
the effective date of the AD. We clarified the wording of paragraph (f) 
to make this clearer.

Statement of the Possibility of Cost and Operational Impact Increasing

    One commenter, Federal Express, stated that cost and operational 
impact could increase if certain RB211-535 models are added to the 
applicability of the proposed AD. The commenter provided no reason for 
its statement.
    We agree. However, additional engine models are not being added, 
and we are specifically excluding the RB211-535 engine in response to 
another comment. We did not change the AD in response to this comment.

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 or 
increase the scope of the AD.

Costs of Compliance

    Based on the service information, we estimate that this AD will 
affect about 46 products of U.S. registry. We also estimate that it 
will take about 1.5 work-hours per product to comply with this AD. The 
average labor rate is $85 per work-hour. No parts are required so parts 
will cost $0 per product. Based on these figures, we estimate the cost 
of the AD on U.S. operators to be $5,865.

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),
    3. Will not affect intrastate aviation in Alaska, and
    4. 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:

[[Page 65943]]

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]

    2. The FAA amends Sec.  39.13 by adding the following new AD:

2011-22-07 Rolls-Royce: Amendment 39-16849. Docket No. FAA-2010-
0993; Directorate Identifier 2010-NE-08-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective November 
29, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce (RR) turbofan engine models 
RB211-524G2-T-19, RB211-524G3-T-19, RB211-524H2-T-19, RB211-524H-T-
36, RB211-Trent 768-60, RB211-Trent 772-60, RB211-Trent 772B-60, 
RB211-Trent 875-17, RB211-Trent 877-17, RB211-Trent 884-17, RB211-
Trent 884B-17, RB211-Trent 892-17, RB211-Trent 892B-17 and RB211-
Trent 895-17 that incorporate RR Service Bulletin (SB) RB.211-72-
D133 or RB.211-72-E902. These engines are installed on, but not 
limited to, Airbus A330 series airplanes; Boeing 747-400 series, 767 
series, and 777 series airplanes.

Reason

    (d) This AD results from:
    Cracking has been found on the inner wall between intermediate 
dilution chutes on a total of five front combustion liners of the 
standard corresponding to Rolls-Royce RB211 Service Bulletin No. 72-
D133. The lives of two of these liners were confirmed to be below 
the currently valid borescope inspection interval. Ultimately, crack 
propagation could result in hot gas breakout with potential of 
downstream component distress and multiple turbine blade release 
beyond containment capabilities of the engine casings. Thus, 
cracking of this nature constitutes a potentially unsafe condition.
    Since Rolls-Royce Service Bulletin No. 72-E902 introduces 
further developments of Rolls-Royce RB211 Service Bulletin No. 72-
D133, engines incorporating Rolls-Royce RB211 Service Bulletin No. 
72-E902 are also considered to be potentially affected and are 
therefore included in the applicability of this AD.

    Since EASA issued its AD, another cracking event has occurred, 
bringing to six the total of crack events of which we are aware. We 
are issuing this AD to detect cracks in the front combustion liner, 
which could result in hot section distress, multiple blade release, 
and possible damage to the airplane.

Actions and Compliance

    (e) Unless already done, do the following actions.

Initial Inspection

    (f) Perform a borescope inspection of the front combustion liner 
inner wall, before accumulating the cyclic limits specified in 
paragraphs (f)(2) and (f)(3) of this AD.
    (1) If you incorporated paragraph 3.A.(2)(a) of RR Alert Service 
Bulletin (ASB) RB.211-72-AF458, Revision 4, dated March 9, 2009, or 
ASB RB.211-72-AF458, Revision 5, dated April 20, 2011, you have 
satisfied the requirements of paragraph (f) of this AD.
    (2) If the engine has a combustion liner installed with:
    (i) A LIFE on the effective date of this AD, that is equal to or 
greater than the initial inspection threshold specified in column 
(b) of Table 1 of this AD or a LIFE on the effective date of this 
AD, that is not known, within 250 cycles after the effective date of 
this AD, perform a borescope inspection as specified in paragraph 
(f) of this AD.
    (ii) A LIFE on the effective date of this AD, that is less than 
the initial inspection threshold specified in column (b) of Table 1 
of this AD, perform the borescope inspection before the LIFE exceeds 
the limit specified in column (c) of Table 1 of this AD.

Repeat Inspection

    (3) Thereafter, repeat the borescope inspection specified in 
paragraph (f) of this AD at intervals not to exceed the cycles 
specified in column (d) of Table 1 of this AD.

                                Table 1--Initial Inspection Thresholds and Limits
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             Column (a)                       Column (b)                Column (c)              Column (d)
----------------------------------------------------------------------------------------------------------------
                                                                    Initial inspection
                                                Initial            limit if LIFE is less     Repeat inspection
            Engine model                  inspectionthreshold        than the initial            interval
                                                                   inspection threshold
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(i) RB211-524G2-T-19, 524G3-T-19 and  1,150 cycles..............  1,400 cycles..........  1,400 cycles.
 524H2-T-19.
(ii) RB211-524H-T-36................  550 cycles................  800 cycles............  800 cycles.
(iii) RB211-Trent 768-60, 772-60 and  1,250 cycles..............  1,500 cycles..........  1,500 cycles.
 772B-60.
(iv) RB211-Trent 892-17, RB211-Trent  750 cycles................  1,000 cycles..........  1,000 cycles.
 884-17, RB211-Trent 884B-17, RB211-
 Trent 877-17, RB211-Trent 875-17,
 RB211-Trent 892B-17 and RB211-Trent
 895-17 engines.
----------------------------------------------------------------------------------------------------------------

Definitions

    (g) This AD defines LIFE as the lowest of:
    (1) The number of cycles-since-new of the combustion liner, or
    (2) The number of cycles-in-service (CIS) since replacement of 
the inner wall, or
    (3) The number of CIS since the inner wall of the combustion 
liner was last borescope-inspected, or inspected by performing 
paragraph 3.A.(2)(a) of RR ASB RB.211-72-AF458, Revision 4, dated 
March 9, 2009 or ASB RB.211-72-AF458, Revision 5, dated April 20, 
2011.

FAA AD Differences

    (h) This AD differs from the Mandatory Continuing Airworthiness 
Information (MCAI) in that the MCAI AD applies to the RB211-Trent 
772C-60 engine, which is not type certificated in the United States. 
The MCAI also allows use of later revisions of the SBs. This AD does 
not.

Other FAA AD Provisions

    (i) 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

    (j) Refer to MCAI European Aviation Safety Agency Airworthiness 
Directive 2009-0243R2, Corrected, dated February 22, 2011, for 
related information.
    (k) Rolls-Royce ASB RB.211-72-AF458, Revision 4, dated March 9, 
2009, or ASB RB.211-72-AF458, Revision 5, dated April 20, 2011, 
provide information on how to do the actions required by this AD. 
For service information identified in this AD, contact Corporate 
Communications at Rolls-Royce plc, PO Box 31, Derby, DE24 8BJ, 
United Kingdom, phone: 011-44-1331-242424, fax: 011-44-1332-249936, 
or e-mail: http://www.rolls-royce.com/contact/civil_team.jsp 
identifying the correspondence as related to airworthiness 
directives.
    (l) Contact Alan Strom, Aerospace Engineer, Engine Certification 
Office, FAA, Engine & Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: alan.strom@faa.gov; 
phone: 781-238-7143; fax: 781-238-7199, for more information about 
this AD.

Material Incorporated by Reference

    (m) None.

[[Page 65944]]

    Issued in Burlington, Massachusetts, on October 18, 2011.
Peter A. White,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-27513 Filed 10-24-11; 8:45 am]
BILLING CODE 4910-13-P