Document ID: FAA-2007-28059-0007
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce plc Turbofan Engines
Posted Date: 2011-10-18T04:00Z

[Federal Register Volume 76, Number 201 (Tuesday, October 18, 2011)]
[Proposed Rules]
[Pages 64283-64285]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-26821]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28059; Directorate Identifier 2007-NE-13-AD]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce plc (RR) Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede an existing airworthiness directive 
(AD) that applies to all RR RB211-Trent 553-61, 553A2-61, 556-61, 
556A2-61, 556B-61, 556B2-61, 560-61, 560A2-61, 768-60, 772-60, 772B-60, 
875-17, 877-17, 884-17, 884B-17, 892-17, 892B-17, and 895-17 turbofan 
engines. The existing AD currently requires inspecting the 
intermediate-pressure (IP) compressor rotor shaft rear balance land for 
cracks. Since we issued that AD, we received reports of one RB211-Trent 
700 and two additional RB211-Trent 800 IP compressor rotor shafts that 
have been found cracked. This proposed AD would continue to require 
initial inspections, add additional inspections, and an optional 
terminating action. The cracking identified above could lead to IP 
compressor rotor shaft failure, uncontained engine failure, and damage 
to the airplane. We are proposing this AD to correct the unsafe 
condition on these products.

DATES: We must receive comments on this proposed AD by December 2, 
2011.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    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 e-mail from 
http://www.rolls-royce.com/contact/civil_team.jsp. You may review 
copies of the referenced service information at the FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803. For information on the availability of this material at the FAA, 
call 781-238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Alan Strom, Aerospace Engineer, Engine 
Certification Office, FAA, 12 New England Executive Park, Burlington, 
MA; phone: 781-238-7143; fax: 781-238-7199; e-mail: alan.strom@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2007-
28059; Directorate Identifier 2007-NE-13-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    On August 25, 2008, we issued AD 2008-18-08, Amendment 39-15665 (73 
FR 52201, September 9, 2008), for all Rolls-Royce plc RB211-Trent 553-
61, 553A2-61, 556-61, 556A2-61, 556B-61, 556B2-61, 560-61, 560A2-61, 
768-60, 772-60, 772B-60, 875-17, 877-17, 884-17, 884B-17, 892-17, 892B-
17, and 895-17 turbofan engines. That AD requires a onetime eddy 
current inspection (ECI) of the rear balance land of the IP compressor 
rotor shaft for cracks. That AD resulted from reports of

[[Page 64284]]

cracking on the rear balance land of IP compressor rotor shafts. We 
issued that AD to detect cracking on the rear balance land of the IP 
compressor rotor shaft. Cracking on the rear balance land on the IP 
compressor rotor shaft can lead to failure of the rotor shaft and 
damage to the engine.

Actions Since Existing AD Was Issued

    Since we issued AD 2008-18-08, (73 FR 52201, September 9, 2008), RR 
reports that they have introduced an optional terminating action to the 
repetitive inspections required by that AD. RR also reported that for 
those operators not adopting the optional terminating action, improved 
inspection methods for the RB211-Trent 700 and RB211-Trent 800 turbofan 
engines are necessary. Also, EASA issued AD 2010-0266, dated December 
21, 2010, and AD 2010-0266R1, dated January 6, 2011, to require 
repetitive on-wing and in-shop ECIs on RB211-Trent 700 and RB211-Trent 
800 engines and repetitive in-shop visual inspections on the RB211-
Trent 500, RB211-Trent 700, and RB211-Trent 800 engines. EASA issued 
their ADs because RR had reported finding additional cracks on the IP 
compressor rotor shaft of two in-service RB211-Trent 800 engines and on 
one in-service RB211-Trent 700 engine. The cracking had initiated from 
frettage marks caused by balance weights. RR reports that stress 
analysis has shown that the cracking presents a possible threat to the 
rotor integrity. We evaluated the data supplied by EASA and RR, and 
concur that the improved inspections for cracks on the balance land of 
the IP compressor rotor shaft are required. We have evaluated the 
optional terminating action and determined it to be effective.
    These cracks, if present, could result in an unsafe condition 
leading to IP compressor rotor shaft failure and damage to the engine.

Relevant Service Information

    We reviewed RR Alert Service Bulletins (ASB) No. RB.211-72-AF260, 
Revision 5, dated July 7, 2011, ASB No. RB.211-72-AG085, Revision 2, 
dated July 7, 2011, ASB No. RB.211-72-AG264, Revision 5, dated March 
21, 2011, ASB No. RB.211-72-AG270, Revision 4, dated March 21, 2011, 
and Service Bulletin No. RB.211-72-G448, Revision 3, dated July 7, 2011 
which provide information for the inspections required by this AD.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of these same type 
designs.

Proposed AD Requirements

    This proposed AD would require:
     For the RB211-Trent 700 and RB211-Trent 800 engines, on 
wing initial and repetitive borescope inspections and when in the shop, 
repetitive ECIs for cracks on the rear balance land; and
     For the RB211-Trent 500 engines, initial and repetitive 
in-shop visual inspections or ECIs for cracks on the rear balance land.
    This proposed AD would also add an optional terminating action to 
the repetitive inspection requirements for the RB211-Trent 700 and 
RB211-Trent 800 engines.

Costs of Compliance

    We estimate that this proposed AD would affect about 136 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 6 work-hours per engine to perform the proposed inspections 
and that the average labor rate is $85 per work-hour. Based on these 
figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $69,360.

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 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),
    (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.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

    Accordingly, 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 FAA amends Sec.  39.13 by removing airworthiness directive 
(AD) 2008-18-08, Amendment 39-15665 (73 FR 52201, September 9, 2008), 
and adding the following new AD:

Rolls-Royce plc: Docket No. FAA-2007-28059; Directorate Identifier 
2007-NE-13-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by December 2, 
2011.

(b) Affected ADs

    This AD supersedes AD 2008-18-08, Amendment 39-15665, (73 FR 
52201, September 9, 2008).

(c) Applicability

    This AD applies to Rolls-Royce plc (RR) RB211-Trent 553-61, 
553A2-61, 556-61, 556A2-61, 556B-61, 556B2-61, 560-61, 560A2-61, 
768-60, 772-60, 772B-60, 875-17, 877-17, 884-17, 884B-17, 892-17, 
892B-17, and 895-17 turbofan engines.

(d) Unsafe Condition

    We are superseding AD 2008-18-08 because additional cracking on 
RB211-Trent 700 and RB211-Trent 800 intermediate-pressure (IP) 
compressor rotor shafts has been found since that AD was issued. 
This cracking could lead to IP compressor rotor shaft failure, 
uncontained engine failure, and damage to the airplane.

[[Page 64285]]

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(f) RB211-Trent 700 Series Engines--Rear Balance Land Inspections

(1) On-Wing Inspections

    Perform on-wing inspections as follows:
    (i) Within 625 cycles-in-service (CIS) after the effective date 
of this AD, borescope inspect the IP compressor rotor shaft rear 
balance land. Use RR Alert Service Bulletin (ASB) No. RB.211-72-
AG270, Revision 4, dated March 21, 2011, sections 3.A.(2)(a) through 
3.A.(2)(c) and 3.A.(3)(a) through 3.A.(3)(c), or 3.B.(2)(a) through 
3.B.(2)(c) and 3.B.(4)(a) through 3.B.(4)(c), to do the inspection.
    (ii) Thereafter, repeat the inspection within every 625 cycles-
since-last inspection (CSLI). You may count CSLI from the last 
borescope inspection or the last eddy current inspection, whichever 
has occurred last.

(2) In-Shop Inspections

    At each shop visit, eddy current inspect (ECI) and visually 
inspect the IP compressor rotor shaft rear balance land, and 
visually inspect the balance weights. Use RR ASB No. RB.211-72-
AG085, Revision 2, dated July 7, 2011, sections 3.A. through 
3.D.(3)(b)(v), except paragraphs 3.D.(3)(a)(ii) and 3.D.(3)(b)(iii) 
to do the inspections.

(3) RB211-Trent 800 Series Engines--Rear Balance Land Inspections

(1) On-Wing Inspections

    (i) Within 475 CIS after the effective date of this AD, 
borescope inspect the IP compressor rotor shaft rear balance land. 
Use RR ASB No. RB.211-72-AG264, Revision 5, dated March 21, 2011, 
sections 3.B.(2)(a) through 3.B.(2)(c) and 3.B.(4)(a) through 
3.B.(4)(c) to do the inspection.
    (ii) Thereafter, repeat the inspection within every 475 CSLI. 
You may count CSLI from the last borescope inspection or the last 
eddy current inspection, whichever has occurred last.

(2) In-Shop Inspections

    At each shop visit, ECI and visually inspect the IP compressor 
rotor rear shaft balance land, and visually inspect the balance 
weights. Use RR ASB No. RB.211-72-AG085, Revision 2, dated July 7, 
2011, sections 3.A. through 3.D.(3)(b)(v), except paragraphs 
3.D.(3)(a)(ii) and 3.D.(3)(b)(iii), to do the inspections.

(h) RB211-Trent 500 Series Engines--In-Shop Rear Balance Land 
Inspections

    At each shop visit, ECI the IP compressor rotor shaft and 
visually inspect the balance weights. Use RR ASB No. RB.211-72-
AF260, Revision 5, dated July 7, 2011 sections 3.A. through 
3.B.(3)(a)(iii) to do the visual inspection, or RR SB No. RB.211-72-
G448, Revision 3, dated July 7, 2011 section 3.D.(1) through 
3.D.(14) to do the ECI.

(i) Definition

    For the purposes of this AD, a shop visit is defined as 
introduction of an engine into a shop, and disassembly sufficient to 
expose the IP compressor module rear face.

(j) Optional Terminating Action for RB211-Trent 700 and RB211-Trent 800 
Engines

    (1) Modifying an RB211-Trent 700 engine as specified in RR SB 
No. RB.211-72-G402, Revision 2, dated July 7, 2011, or RR SB No. 
RB.211-72-G402, Revision 1, dated January 11, 2011, is terminating 
action for paragraph (f)(2) of this AD.
    (2) Modifying an RB211-Trent 800 engine as specified in RR SB 
No. RB.211-72-G401, Revision 2, dated July 5, 2011, or SB No. 
RB.211-72-G401, Revision 1, dated January 11, 2011, is terminating 
action for paragraph (h)(2) of this AD.

(k) Previous Credit

    (1) For RB211-Trent 700 series engines:
    (i) On-wing inspections done before the effective date of this 
AD using RR ASB No. RB.211-72-AG270, Revision 1, dated December 14, 
2009, or Revision 2, dated December 21, 2010, or Revision 3, dated 
February 25, 2011, meet the inspection requirements in paragraph (f) 
of this AD.
    (ii) In-shop inspections done before the effective date of this 
AD using RR ASB No. RB.211-72-AG085, Revision 1, dated September 27, 
2010, meet the inspection requirements in paragraph (g) of this AD.
    (2) For RB211-Trent 800 series engines:
    (i) On-wing inspections done before the effective date of this 
AD using RR ASB No. RB.211-72-AG264, Revision 3, dated December 21, 
2010, or Revision 4, dated February 25, 2011, meet the inspection 
requirements in paragraph (h) of this AD.
    (ii) In-shop inspections done before the effective date of this 
AD using RR ASB No. RB.211-72-AG085, Revision 1, dated September 27, 
2010, meet the inspection requirements in paragraph (i) of this AD.
    (3) For RB211-Trent 500 series engines:
    (i) In-shop visual inspections done before the effective date of 
this AD using RR ASB No. RB.211-72-AF260, Revision 4, dated July 28, 
2009, meet the inspection requirements in paragraph (j) of this AD.
    (ii) In-shop ECIs done before the effective date of this AD 
using RR ASB No. RB.211-72-G448, Revision 2, dated December 23, 
2010, meet the ECI requirements in paragraph (j) of this AD.

(l) Alternative Methods of Compliance (AMOCs)

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

(m) Related Information

    (1) For more information about this AD, contact Alan Strom, 
Aerospace Engineer, Engine Certification Office, FAA, 12 New England 
Executive Park, Burlington, MA; phone: 781-238-7143; fax: 781-238-
7199; e-mail: alan.strom@faa.gov.
    (2) 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 e-mail from http://www.rolls-royce.com/contact/civil_team.jsp. You may review copies of the referenced service 
information at the FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803. For information on the 
availability of this material at the FAA, call 781-238-7125.

    Issued in Burlington, Massachusetts, on October 6, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-26821 Filed 10-17-11; 8:45 am]
BILLING CODE 4910-13-P