Airworthiness Directives; Rolls-Royce plc (RR) RB211-524 Series and RB211 Trent 500, 700, and 800 Series Turbofan Engines, 24793-24796 [2011-10517]

Download as PDF 24793 Rules and Regulations Federal Register Vol. 76, No. 85 Tuesday, May 3, 2011 This section of the FEDERAL REGISTER contains regulatory documents having general applicability and legal effect, most of which are keyed to and codified in the Code of Federal Regulations, which is published under 50 titles pursuant to 44 U.S.C. 1510. The Code of Federal Regulations is sold by the Superintendent of Documents. Prices of new books are listed in the first FEDERAL REGISTER issue of each week. DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service 9 CFR Parts 93, 94, and 95 [Docket No. APHIS–2006–0074] RIN 0579–AC36 Highly Pathogenic Avian Influenza Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule; reopening of comment period. AGENCY: We are reopening the comment period for our interim rule that amended the regulations concerning the importation of animals and animal products to prohibit or restrict the importation of bird and poultry products from regions where any subtype of highly pathogenic avian influenza is considered to exist. The interim rule also imposed restrictions concerning importation of live poultry and birds that have been vaccinated for certain types of avian influenza, or that have moved through regions where any subtype of highly pathogenic avian influenza is considered to exist. This action will allow interested persons additional time to prepare and submit comments. DATES: We will consider all comments that we receive on or before May 18, 2011. ADDRESSES: You may submit comments by either of the following methods: • Federal eRulemaking Portal: Go to https://www.regulations.gov/fdmspublic/ component/ main?main=DocketDetail&d=APHIS– 2006–0074 to submit or view comments and to view supporting and related materials available electronically. • Postal Mail/Commercial Delivery: Please send one copy of your comment to Docket No. APHIS–2006–0074, SUMMARY: Regulatory Analysis and Development, PPD, APHIS, Station 3A–03.8, 4700 River Road Unit 118, Riverdale, MD 20737–1238. Please state that your comment refers to Docket No. APHIS– 2006–0074. Reading Room: You may read any comments that we receive on this docket in our reading room. The reading room is located in room 1141 of the USDA South Building, 14th Street and Independence Avenue, SW., Washington, DC. Normal reading room hours are 8 a.m. to 4:30 p.m., Monday through Friday, except holidays. To be sure someone is there to help you, please call (202) 690–2817 before coming. Other Information: Additional information about APHIS and its programs is available on the Internet at https://www.aphis.usda.gov. Dr. Julia Punderson, Senior Staff Veterinarian, National Center for Import and Export, Animal Health Policy and Programs, VS, APHIS, 4700 River Road Unit 38, Riverdale, MD 20737; (301) 734–4356. FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: Background On January 24, 2011, we published in the Federal Register (76 FR 4046–4056, Docket No. APHIS–2006–0074) an interim rule that amended the regulations governing the importation into the United States of specified animals and animal products and byproducts in order to prohibit or restrict the importation of bird and poultry products from regions where any subtype of highly pathogenic avian influenza is considered to exist. The interim rule was effective upon publication. Comments on the interim rule were required to be received on or before March 25, 2011. We are reopening the comment period on Docket No. APHIS– 2006–0074 for an additional 15 days. This action will allow interested persons additional time to prepare and submit comments. We will also consider all comments received between March 26, 2011, and the date of this notice. Authority: 7 U.S.C. 450, 1622, 7701–7772, 7781–7786, and 8301–8317; 21 U.S.C. 136 and 136a; 31 U.S.C. 9701; 7 CFR 2.22, 2.80, and 371.4. Done in Washington, DC, this 28th day of April 2011. Gregory L. Parham, Administrator, Animal and Plant Health Inspection Service. [FR Doc. 2011–10715 Filed 5–2–11; 8:45 am] BILLING CODE 3410–34–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2010–0562; Directorate Identifier 2009–NE–29–AD; Amendment 39– 16669; AD 2011–09–07] RIN 2120–AA64 Airworthiness Directives; Rolls-Royce plc (RR) RB211–524 Series and RB211 Trent 500, 700, and 800 Series Turbofan Engines Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: 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: SUMMARY: During manufacture of a number of HP Compressor Stage 1 and 2 discs with axial dovetail slots, anomalies at the disc post corners have been found. Fatigue crack initiation and subsequent crack propagation at the disc post may result in release of two blades and the disc post. This may potentially be beyond the containment capabilities of the engine casings. Thus, these anomalies present at the disc posts constitute a potentially unsafe condition. We are issuing this AD to detect cracks in the high-pressure compressor (HPC) Stage 1 and 2 disc posts, which could result in failure of the disc post and release of HPC blades, release of uncontained engine debris, and damage to the airplane. DATES: This AD becomes effective June 7, 2011. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of June 7, 2011. ADDRESSES: The Docket Operations office is located at Docket Management 24794 Federal Register / Vol. 76, No. 85 / Tuesday, May 3, 2011 / Rules and Regulations 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 and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: alan.strom@faa.gov; telephone (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 June 15, 2010 (75 FR 33738). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states that: During manufacture of a number of HP Compressor Stage 1 and 2 discs with axial dovetail slots, anomalies at the disc post corners have been found. Fatigue crack initiation and subsequent crack propagation at the disc post may result in release of two blades and the disc post. This may potentially be beyond the containment capabilities of the engine casings. Thus, these anomalies present at the disc posts constitute a potentially unsafe condition. For the reasons described above, this AD requires repetitive inspections of the axial dovetail slots and follow-on corrective action, depending on findings. Comments We gave the public the opportunity to participate in developing this AD. We considered the comments received. Request To Change the Definition of a Shop Visit Five commenters request that we change the criteria for carrying out the inspections to be consistent with the European Aviation Safety Agency (EASA) AD. The commenters ask that we require performing the inspections at the first shop visit after accumulating 1,000 hours-since-new (HSN) and whenever a Level 3 (Refurbishment) or Level 4 (Overhaul) shop visit occurs. The commenters feel that requiring the inspections any time a major flange is separated would result in more inspections than required by the EASA AD. Some of the inspections would cost significantly more than what is estimated in the Costs of Compliance section of the proposed AD. We partially agree. We agree that the current wording would result in more inspections than required by the EASA AD, and some of the inspections would cost significantly more than what we estimated in the Costs of Compliance section of the proposed AD. We do not agree with using the Level 3 or Level 4 criteria as a definition of ‘‘engine shop visit’’ for the purpose of this AD. The definitions of Level 3 and Level 4 are not specific enough to ensure the inspections are conducted frequently enough to prevent the unsafe condition. We changed the definition of shop visit in paragraph (f) of the proposed AD from ‘‘For * * * an ‘‘engine shop visit’’ is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges, * * *’’ to ‘‘For * * * an ‘‘engine shop visit’’ is whenever the engine high-pressure compressor module is separated from the intermediate case.’’ Request To Change the Summary of the Proposed AD One commenter, RR, asks us to consider changing the Summary from ‘‘Thus, these anomalies present at the disc posts constitute a potentially unsafe condition’’ to ‘‘Thus, if these anomalies are present at the disc posts, they constitute a potentially unsafe condition.’’ The commenter believes that the MCAI description implies that all discs have the anomalies in question. The AD does not assume that to be true. We don’t agree. The second paragraph of the Summary quotes the EASA AD. We did not change the AD. Request To Correct a Disc Part Number The same commenter asks us to change paragraph (c)(1) part number (P/ N) ‘‘FK20195’’ to ‘‘FW20195.’’ The commenter states that the NPRM contains a typographical error. We agree. We changed the part number in paragraph (c)(1) of the proposed AD from ‘‘FK20195’’ to ‘‘FW20195.’’ Request To Change the Unsafe Condition Statement The same commenter asks us to change the unsafe condition statement in the Summary and in paragraph (d) of the proposed AD from ‘‘* * * failure of the disc post, which could result in failure of the disc post and HPC blades, release * * * airplane’’ to ‘‘* * * failure of the disc post, resulting in release of HPC blades, release * * * airplane.’’ The commenter states the NPRM implies that high-pressure compressor blades may themselves fail, when in fact they are released as a result of disk post failure. We agree. We changed the unsafe condition statement in the Summary and in paragraph (d) of the proposed AD to ‘‘which could result in failure of the disc post, release of HPC blades, release of uncontained debris, * * * airplane.’’ Request To Ensure the Disc is Cleaned before Inspection The same commenter asks us to change paragraph (e)(1) of the proposed AD from ‘‘Perform a * * * later. Use paragraph 3.E.(1) through 3.E.(10)(i) * * * inspections’’ to ‘‘Clean and perform * * * later. Use paragraph 3.A through 3.E.(10)(i) * * * inspections.’’ The commenter believes the change will ensure adequate cleaning before inspection, which is essential to make sure the small cracks are visible. We agree. Because the corrective action is looking for small cracks underneath a dry film lubricant coating, the cleaning procedure prior to fluorescent penetrant inspection (FPI) is critical to the corrective action. We changed paragraph (e)(1) of the proposed AD to ‘‘Clean and perform * * * later. Use paragraph 3.A through 3.E.(11) * * * inspections.’’ We also added paragraph 3.E.(11) to ensure that the blades will be re-coated prior to reinstallation. Request To Change Nomenclature of HPC Rotor Shaft One commenter, Hawaiian Airlines, asks us to change ‘‘HPC rotor shaft’’ to ‘‘HP compressor drum.’’ The commenter states that the HPC drum in the Trent 700 engine is a six stage rotor and is referred to as the ‘‘HPC rotor shaft.’’ Since each engine model has different nomenclature, they request that we use a common name when we refer to the subject part such as ‘‘HP compressor Drum.’’ The commenter believes that this will ensure a common understanding of the parts involved. We don’t agree. While the service bulletin uses the term ‘‘HPC drum,’’ the AD consistently refers to the HPC disks by stage number. 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 would affect about 371 products of U.S. registry. We also estimate that it would take about 20 work-hours per product to comply with this AD. The average labor rate is $85 per work-hour. No parts would be Federal Register / Vol. 76, No. 85 / Tuesday, May 3, 2011 / Rules and Regulations required per product. Based on these figures, we estimate the cost of the AD on U.S. operators to be $630,700. 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 https:// 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, 24795 the FAA amends 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. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new AD: ■ 2011–09–07 Rolls-Royce plc (RR): Amendment 39–16669. Docket No. FAA–2010–0562; Directorate Identifier 2009–NE–29–AD. Effective Date (a) This airworthiness directive (AD) becomes effective June 7, 2011. Affected ADs (b) None. Applicability (c) This AD applies to RR model RB211– 524G2–T–19, –524G3–T–19, –524H–T–36, and –524H2–T–19; and RB211 Trent 553–61, 553A2–61, 556–61, 556A2–61, 556B–61, 556B2–61, 560–61, 560A2–61; RB211 Trent 768–60, 772–60, 772B–60; and RB211 Trent 875–17, 877–17, 884–17, 884B–17, 892–17, 892B–17, and 895–17 turbofan engines that have a high-pressure (HP) compressor stage 1 to 4 rotor disc with a part number (P/N) listed in Table 1 of this AD. These engines are installed on, but not limited to, Boeing 747, 767, and 777 series airplanes and Airbus A330 and A340 series airplanes. TABLE 1—AFFECTED HP COMPRESSOR STAGE 1 TO 4 ROTOR DISC P/NS BY ENGINE MODEL Engine model HP compressor stage 1 to 4 rotor disc P/N (1) RB211–524G2–T–19, –524G3–T–19, –524H–T–36, and –524H2– T–19. (2) RB211 Trent 553–61, 553A2–61, 556–61, 556A2–61, 556B–61, 556B2–61, 560–61, and 560A2–61. (3) RB211 Trent 768–60, 772–60, and 772B–60 .................................... (4) RB211 Trent 875–17, 877–17, 884–17, 884B–17, 892–17, 892B– 17, and 895–17. Reason (d) This AD results from reports that: During manufacture of a number of HP Compressor Stage 1 and 2 discs with axial dovetail slots, anomalies at the disc post corners have been found. Fatigue crack initiation and subsequent crack propagation at the disc post may result in release of two blades and the disc post. This may potentially be beyond the containment capabilities of the engine casings. Thus, these anomalies present at the disc posts constitute a potentially unsafe condition. We are issuing this AD to detect cracks in the high-pressure compressor (HPC) Stage 1 and 2 disc posts, which could result in failure of FW20195, FK25502, or FW23711. FK30524. FK22745, FK24031, FK26185, FK23313, FK25502, FW20195, FW20196, FW20197, FW20638, or FW23711. FK24009, FK26167, FK32580, FW11590, or FW61622. the disc post and release of HPC blades, release of uncontained engine debris, and damage to the airplane. Actions and Compliance (e) Unless already done, do the following actions. (1) Clean and perform a fluorescent penetrant inspection of the HP compressor stage 1 to 4 rotor discs at the first shop visit after accumulating 1000 cycles since new on the stage 1 to 4 rotor disks or at the next shop visit after the effective date of this AD, whichever occurs later. Use paragraph 3.A through 3.E.(11) of the Accomplishment Instructions of Rolls-Royce Alert Service FK32129, Bulletin (ASB) RB.211–72–AF964, Revision 1, dated June 6, 2008 to do the inspections. (2) Thereafter at every engine shop visit, perform the inspection specified by paragraph (e)(1) of this AD. Definitions (f) For the purpose of this AD, an ‘‘engine shop visit’’ is whenever the engine highpressure compressor module is separated from the intermediate case. Other FAA AD Provisions (g) Alternative Methods of Compliance (AMOCs): The Manager, Engine Certification Office, FAA, has the authority to approve 24796 Federal Register / Vol. 76, No. 85 / Tuesday, May 3, 2011 / Rules and Regulations AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Related Information (h) See European Aviation Safety Agency Airworthiness Directive 2009–0073R1, dated April 8, 2009, for related information. (i) Contact Alan Strom, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: alan.strom@faa.gov; telephone (781) 238–7143; fax (781) 238–7199, for more information about this AD. Material Incorporated by Reference (j) You must use Rolls-Royce Alert Service Bulletin RB.211–72–AF964, Revision 1, dated June 6, 2008, 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 plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; phone: 011 44 1332 242424, fax: 011 44 1332 249936; e-mail: tech.help@rolls-royce.com. (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: https:// www.archives.gov/federal-register/cfr/ibrlocations.html. Issued in Burlington, Massachusetts, on April 12, 2011. Peter A. White, Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 2011–10517 Filed 5–2–11; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2008–1165; Directorate Identifier 2008–NE–38–AD; Amendment 39– 16685; AD 2011–10–04] RIN 2120–AA64 Airworthiness Directives; Rolls-Royce plc RB211–Trent 800 Series Turbofan Engines Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: 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 SUMMARY: another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: During manufacture of high-pressure (HP) compressor stage 1 discs, a small number of parts have been rejected due to a machining defect that was found during inspection. Analysis of the possibility of less severe examples having been undetected and passed into service has concluded that action is required to reduce the risk of failure. It was therefore necessary to reduce the life limit. The HP compressor stage 1 disc is part of the HP compressor stage 1–4 shaft, part number (P/N) FK32580. We are issuing this AD to prevent failure of the HP compressor stage 1 disc, uncontained engine failure, and damage to the airplane. DATES: This AD becomes effective June 7, 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; telephone (781) 238–7143; fax (781) 238–7199. SUPPLEMENTARY INFORMATION: Discussion We issued a notice of proposed rulemaking (NPRM) and a supplemental notice of proposed rulemaking (SNPRM) 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 February 18, 2009 (74 FR 7563) and that SNPRM was published in the Federal Register on October 4, 2010 (75 FR 61114). That SNPRM proposed to correct an unsafe condition for the specified products. The MCAI states that: During manufacture of high-pressure (HP) compressor stage 1 discs, a small number of parts have been rejected due to a machining defect that was found during inspection. Analysis of the possibility of less severe examples having been undetected and passed into service has concluded that action is required to reduce the risk of failure. It was therefore necessary to reduce the life limit. The HP compressor stage 1 disc is part of the HP compressor stage 1–4 shaft, P/N FK32580. Since we issued the original NPRM on February 10, 2009 (74 FR 7563, February 18, 2009), EASA issued AD 2010–0087, dated May 5, 2010 (corrected May 6, 2010), which retains certain requirements of superseded EASA AD 2008–0099, and imposes more restrictive life limits in the Heavy Flight Profile Parts. 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 Revise the Compliance Times Four commenters, American Airlines, Delta Airlines, Rolls-Royce plc, and The Boeing Company, request that we revise the compliance times to be consistent with the service bulletin and the airworthiness limitations section (ALS) of the engine manual. Doing this would account for the later AD release date and for the entire Trent 800 series fleet instead of just certain US operators’ expected cyclic usage. The commenters state that the proposed requirements would have a severe adverse economic impact to operators relative to the service bulletin requirements. The simplified compliance requirements in the SNPRM relative to the service bulletin requirements, may not accurately reflect the risk of an uncontained event, and are confusing. We do not agree. The requirements in the SNPRM were developed to minimize the risk of uncontained disc failure, based on the age of the parts in the field at the time the SNPRM was issued. The service bulletin requirements were developed at a time when the age of the parts in service was lower than when the SNPRM was issued. Because the risk of failure increases as the age of the parts in the field increase, any revision to the requirements of the SNPRM would again have to take the increased age of the parts in service into account. As such, an analysis would result in removal requirements more stringent than the requirements in the SNPRM, and a follow-on NPRM would be required. Therefore, we determined that it is in the public interest to keep the removal requirements the same as published in the SNPRM. We did not change the AD. Request for Clarity and Interpretation Delta Airlines states that it would be helpful if we could provide some clarity in the AD as to how an operator should interpret the differing information between the AD, the ALS of the RollsRoyce Time Limits Manual, and the service bulletin. The commenter is concerned that there will be three locations where the life limit of the

Agencies

[Federal Register Volume 76, Number 85 (Tuesday, May 3, 2011)]
[Rules and Regulations]
[Pages 24793-24796]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-10517]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0562; Directorate Identifier 2009-NE-29-AD; 
Amendment 39-16669; AD 2011-09-07]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc (RR) RB211-524 Series 
and RB211 Trent 500, 700, and 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:

    During manufacture of a number of HP Compressor Stage 1 and 2 
discs with axial dovetail slots, anomalies at the disc post corners 
have been found. Fatigue crack initiation and subsequent crack 
propagation at the disc post may result in release of two blades and 
the disc post. This may potentially be beyond the containment 
capabilities of the engine casings. Thus, these anomalies present at 
the disc posts constitute a potentially unsafe condition.

    We are issuing this AD to detect cracks in the high-pressure 
compressor (HPC) Stage 1 and 2 disc posts, which could result in 
failure of the disc post and release of HPC blades, release of 
uncontained engine debris, and damage to the airplane.

DATES: This AD becomes effective June 7, 2011. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in this AD as of June 7, 2011.

ADDRESSES: The Docket Operations office is located at Docket Management

[[Page 24794]]

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 and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
alan.strom@faa.gov; telephone (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 June 15, 2010 (75 FR 
33738). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states that:

    During manufacture of a number of HP Compressor Stage 1 and 2 
discs with axial dovetail slots, anomalies at the disc post corners 
have been found. Fatigue crack initiation and subsequent crack 
propagation at the disc post may result in release of two blades and 
the disc post. This may potentially be beyond the containment 
capabilities of the engine casings. Thus, these anomalies present at 
the disc posts constitute a potentially unsafe condition.
    For the reasons described above, this AD requires repetitive 
inspections of the axial dovetail slots and follow-on corrective 
action, depending on findings.

Comments

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

Request To Change the Definition of a Shop Visit

    Five commenters request that we change the criteria for carrying 
out the inspections to be consistent with the European Aviation Safety 
Agency (EASA) AD. The commenters ask that we require performing the 
inspections at the first shop visit after accumulating 1,000 hours-
since-new (HSN) and whenever a Level 3 (Refurbishment) or Level 4 
(Overhaul) shop visit occurs. The commenters feel that requiring the 
inspections any time a major flange is separated would result in more 
inspections than required by the EASA AD. Some of the inspections would 
cost significantly more than what is estimated in the Costs of 
Compliance section of the proposed AD.
    We partially agree. We agree that the current wording would result 
in more inspections than required by the EASA AD, and some of the 
inspections would cost significantly more than what we estimated in the 
Costs of Compliance section of the proposed AD. We do not agree with 
using the Level 3 or Level 4 criteria as a definition of ``engine shop 
visit'' for the purpose of this AD. The definitions of Level 3 and 
Level 4 are not specific enough to ensure the inspections are conducted 
frequently enough to prevent the unsafe condition. We changed the 
definition of shop visit in paragraph (f) of the proposed AD from ``For 
* * * an ``engine shop visit'' is the induction of an engine into the 
shop for maintenance involving the separation of pairs of major mating 
engine flanges, * * *'' to ``For * * * an ``engine shop visit'' is 
whenever the engine high-pressure compressor module is separated from 
the intermediate case.''

Request To Change the Summary of the Proposed AD

    One commenter, RR, asks us to consider changing the Summary from 
``Thus, these anomalies present at the disc posts constitute a 
potentially unsafe condition'' to ``Thus, if these anomalies are 
present at the disc posts, they constitute a potentially unsafe 
condition.'' The commenter believes that the MCAI description implies 
that all discs have the anomalies in question. The AD does not assume 
that to be true.
    We don't agree. The second paragraph of the Summary quotes the EASA 
AD. We did not change the AD.

Request To Correct a Disc Part Number

    The same commenter asks us to change paragraph (c)(1) part number 
(P/N) ``FK20195'' to ``FW20195.'' The commenter states that the NPRM 
contains a typographical error.
    We agree. We changed the part number in paragraph (c)(1) of the 
proposed AD from ``FK20195'' to ``FW20195.''

Request To Change the Unsafe Condition Statement

    The same commenter asks us to change the unsafe condition statement 
in the Summary and in paragraph (d) of the proposed AD from ``* * * 
failure of the disc post, which could result in failure of the disc 
post and HPC blades, release * * * airplane'' to ``* * * failure of the 
disc post, resulting in release of HPC blades, release * * * 
airplane.'' The commenter states the NPRM implies that high-pressure 
compressor blades may themselves fail, when in fact they are released 
as a result of disk post failure.
    We agree. We changed the unsafe condition statement in the Summary 
and in paragraph (d) of the proposed AD to ``which could result in 
failure of the disc post, release of HPC blades, release of uncontained 
debris, * * * airplane.''

Request To Ensure the Disc is Cleaned before Inspection

    The same commenter asks us to change paragraph (e)(1) of the 
proposed AD from ``Perform a * * * later. Use paragraph 3.E.(1) through 
3.E.(10)(i) * * * inspections'' to ``Clean and perform * * * later. Use 
paragraph 3.A through 3.E.(10)(i) * * * inspections.'' The commenter 
believes the change will ensure adequate cleaning before inspection, 
which is essential to make sure the small cracks are visible.
    We agree. Because the corrective action is looking for small cracks 
underneath a dry film lubricant coating, the cleaning procedure prior 
to fluorescent penetrant inspection (FPI) is critical to the corrective 
action. We changed paragraph (e)(1) of the proposed AD to ``Clean and 
perform * * * later. Use paragraph 3.A through 3.E.(11) * * * 
inspections.'' We also added paragraph 3.E.(11) to ensure that the 
blades will be re-coated prior to re-installation.

Request To Change Nomenclature of HPC Rotor Shaft

    One commenter, Hawaiian Airlines, asks us to change ``HPC rotor 
shaft'' to ``HP compressor drum.'' The commenter states that the HPC 
drum in the Trent 700 engine is a six stage rotor and is referred to as 
the ``HPC rotor shaft.'' Since each engine model has different 
nomenclature, they request that we use a common name when we refer to 
the subject part such as ``HP compressor Drum.'' The commenter believes 
that this will ensure a common understanding of the parts involved.
    We don't agree. While the service bulletin uses the term ``HPC 
drum,'' the AD consistently refers to the HPC disks by stage number.

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 would 
affect about 371 products of U.S. registry. We also estimate that it 
would take about 20 work-hours per product to comply with this AD. The 
average labor rate is $85 per work-hour. No parts would be

[[Page 24795]]

required per product. Based on these figures, we estimate the cost of 
the AD on U.S. operators to be $630,700.

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 https://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 AD:

2011-09-07 Rolls-Royce plc (RR): Amendment 39-16669. Docket No. FAA-
2010-0562; Directorate Identifier 2009-NE-29-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective June 7, 
2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to RR model RB211-524G2-T-19, -524G3-T-19, -
524H-T-36, and -524H2-T-19; and RB211 Trent 553-61, 553A2-61, 556-
61, 556A2-61, 556B-61, 556B2-61, 560-61, 560A2-61; RB211 Trent 768-
60, 772-60, 772B-60; and RB211 Trent 875-17, 877-17, 884-17, 884B-
17, 892-17, 892B-17, and 895-17 turbofan engines that have a high-
pressure (HP) compressor stage 1 to 4 rotor disc with a part number 
(P/N) listed in Table 1 of this AD. These engines are installed on, 
but not limited to, Boeing 747, 767, and 777 series airplanes and 
Airbus A330 and A340 series airplanes.

 Table 1--Affected HP Compressor Stage 1 to 4 Rotor Disc P/Ns by Engine
                                  Model
------------------------------------------------------------------------
                                            HP compressor stage 1 to 4
              Engine model                        rotor disc P/N
------------------------------------------------------------------------
(1) RB211-524G2-T-19, -524G3-T-19, -     FW20195, FK25502, or FW23711.
 524H-T-36, and -524H2-T-19.
(2) RB211 Trent 553-61, 553A2-61, 556-   FK30524.
 61, 556A2-61, 556B-61, 556B2-61, 560-
 61, and 560A2-61.
(3) RB211 Trent 768-60, 772-60, and      FK22745, FK24031, FK26185,
 772B-60.                                 FK23313, FK25502, FK32129,
                                          FW20195, FW20196, FW20197,
                                          FW20638, or FW23711.
(4) RB211 Trent 875-17, 877-17, 884-17,  FK24009, FK26167, FK32580,
 884B-17, 892-17, 892B-17, and 895-17.    FW11590, or FW61622.
------------------------------------------------------------------------

Reason

    (d) This AD results from reports that:
    During manufacture of a number of HP Compressor Stage 1 and 2 
discs with axial dovetail slots, anomalies at the disc post corners 
have been found. Fatigue crack initiation and subsequent crack 
propagation at the disc post may result in release of two blades and 
the disc post. This may potentially be beyond the containment 
capabilities of the engine casings. Thus, these anomalies present at 
the disc posts constitute a potentially unsafe condition.

We are issuing this AD to detect cracks in the high-pressure 
compressor (HPC) Stage 1 and 2 disc posts, which could result in 
failure of the disc post and release of HPC blades, release of 
uncontained engine debris, and damage to the airplane.

Actions and Compliance

    (e) Unless already done, do the following actions.
    (1) Clean and perform a fluorescent penetrant inspection of the 
HP compressor stage 1 to 4 rotor discs at the first shop visit after 
accumulating 1000 cycles since new on the stage 1 to 4 rotor disks 
or at the next shop visit after the effective date of this AD, 
whichever occurs later. Use paragraph 3.A through 3.E.(11) of the 
Accomplishment Instructions of Rolls-Royce Alert Service Bulletin 
(ASB) RB.211-72-AF964, Revision 1, dated June 6, 2008 to do the 
inspections.
    (2) Thereafter at every engine shop visit, perform the 
inspection specified by paragraph (e)(1) of this AD.

Definitions

    (f) For the purpose of this AD, an ``engine shop visit'' is 
whenever the engine high-pressure compressor module is separated 
from the intermediate case.

Other FAA AD Provisions

    (g) Alternative Methods of Compliance (AMOCs): The Manager, 
Engine Certification Office, FAA, has the authority to approve

[[Page 24796]]

AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19.

Related Information

    (h) See European Aviation Safety Agency Airworthiness Directive 
2009-0073R1, dated April 8, 2009, for related information.
    (i) Contact Alan Strom, Aerospace Engineer, Engine Certification 
Office, FAA, Engine and Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: alan.strom@faa.gov; 
telephone (781) 238-7143; fax (781) 238-7199, for more information 
about this AD.

Material Incorporated by Reference

    (j) You must use Rolls-Royce Alert Service Bulletin RB.211-72-
AF964, Revision 1, dated June 6, 2008, 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 plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; 
phone: 011 44 1332 242424, fax: 011 44 1332 249936; e-mail: 
royce.com">tech.help@rolls-royce.com.
    (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: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Burlington, Massachusetts, on April 12, 2011.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2011-10517 Filed 5-2-11; 8:45 am]
BILLING CODE 4910-13-P