2010-24888. Airworthiness Directives; Rolls-Royce plc RB211-524 Series, -535 Series, RB211 Trent 700 Series, and RB211 Trent 800 Series Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed 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 proposing this AD to detect cracks in the front combustion liner, which could result in hot section distress, uncontained multiple blade release and possible damage to the aircraft.

DATES:

We must receive comments on this proposed AD by November 19, 2010.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• Mail: Docket Management Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-0001.
• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

Contact Rolls-Royce plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; telephone: [phone]; fax: [phone] for the service information identified in this proposed AD.

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 proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone [phone]) is the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone].

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-2010-0993; Directorate Identifier 2010-NE-08-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 based on 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 with FAA personnel concerning this proposed AD. Using the search function of the Web site, anyone can find and read the comments in any of our dockets, including, if provided, the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78).

Discussion

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA Airworthiness Directive 2009-0243R1, dated November 26, 2009 (referred to after this as “the MCAI”), to correct an unsafe condition for the specified products. The MCAI states:

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.

You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Rolls-Royce plc has issued Alert Service Bulletin RB.211-72-AF458, Revision 4, dated March 9, 2009. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of the United Kingdom, and is approved for operation in the United States. Pursuant to our bilateral agreement with the United Kingdom, they have notified us of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all information provided by EASA and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

Costs of Compliance

Based on the service information, we estimate that this proposed AD would affect about 239 products of U.S. registry. We also estimate that it would take about 1.5 work-hours per product to comply with this proposed AD. The average labor rate is $85 per work-hour. No parts are required so parts would cost about $0 per product. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $30,473.

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 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 this proposed regulation:

1. Is not a “significant regulatory action” under Executive Order 12866;

2. Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

3. 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 proposed AD and placed it in the AD docket.

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.

§ 39.13

[Amended]

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

Rolls-Royce plc: Docket No. FAA-2010-0993; Directorate Identifier 2010-NE-08-AD.

Comments Due Date

(a) We must receive comments by November 19, 2010.

Affected Airworthiness Directives (ADs)

(b) None.

Applicability

(c) This AD applies to Rolls-Royce (RR) engine models RB211-524G2-T-19, RB211-524G3-T-19, RB211-524H2-T-19, RB211-524H-T-36, RB211-535E4-37, RB211-535E4-B-37, RB211-535E4-C-37, RB211-535E4-B-75, RB211 Trent 768-60, RB211 Trent 772-60, RB211 Trent 772B-60, RB211-Trent 892-17, RB211-Trent 884-17, RB211-Trent 884B-17, RB211-Trent 877-17, RB211-Trent 875-17, RB211-Trent 892-17, RB211-Trent 892B-17 and RB211-Trent 895-17 engines, that incorporate RR Service Bulletins (SBs) 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, 757 series, 767 series, and 777 series airplanes; and Tupolev Tu204 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.

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

Actions and Compliance

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

Inspection

(f) Perform a borescope inspection as specified in section 3. Accomplishment instructions, subsection A. Borescope Inspection of Rolls-Royce RB211 Alert Service Bulletin (ASB) RB.211-72-AF458 Revision 4, dated March 9, 2009, before the limits specified below:

Initial Inspection

(1) 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) in Table 1 of this AD, or

(ii) A LIFE on the effective date of this AD, that is not known, carry out the action specified in paragraph (f) of this AD within 250 cycles after the effective date of this AD.

(iii) 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

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

Table 1—Initial Inspection Thresholds and Limits

Column (a)	Column (b)	Column (c)	Column (d)
Engine Model	Initial inspection threshold	Initial inspection limit if LIFE is less than the initial inspection threshold	Repeat inspection interval
(i) RB211-524G2-T-19, 524G3-T-19 and 524H2-T-19	1,150 cycles	1,400 cycles	1,400 cycles.
(ii) RB211-524H-T-36	550 cycles	800 cycles	800 cycles.
(iii) RB211-535E4-37, E4-B-37 and E4-C-37	550 cycles	800 cycles	800 cycles.
(iv) RB211-535E4-B-75	550 cycles	800 cycles	800 cycles.
(v) RB211-Trent 768-60, 772-60 and 772B-60	1,250 cycles	1,500 cycles	1,500 cycles.
(vi) RB211-Trent 892-17, RB211-Trent 884-17, RB211-Trent 884B-17, RB211-Trent 877-17, RB211-Trent 875-17, RB211-Trent 892B-17 and RB211-Trent 895-17 engines	750 cycles	1,000 cycles	1,000 cycles.

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 combustion liner was last inspected in accordance with section 3. Accomplishment instructions, subsection A. Borescope Inspection of Rolls-Royce RB211 Series Propulsion System Series Non-Modification Service Bulletin No. RB.211-72-AF458 Revision 2, dated December 21, 2007.

FAA AD Differences

(h) This AD differs from the Mandatory Continuing Airworthiness Information (MCAI) and or service information in that the MCAI AD applies to the RB211 Trent 772C-60 engine, which isn't type certificated in the United States.

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 2009-0243R1, dated November 26, 2009, and Rolls-Royce ASB RB.211-72-AF458, Revision 4, dated March 9, 2009, for related information. Contact Rolls-Royce plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; telephone: [phone]; fax: [phone], for a copy of this service information.

(k) Contact Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; e-mail: [e-mail]; telephone [phone]; fax [phone], for more information about this AD.

Issued in Burlington, Massachusetts, on September 27, 2010.

Peter A. White,

Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service.