AD 2000-03-07

This amendment adopts a new airworthiness directive (AD) that is applicable to Rolls-Royce plc RB211-524H-36 series turbofan engines. This action requires, prior to further flight, installing an improved combustion liner with a strengthened head and improved heat shields. This amendment is prompted by a report of burn through of a combustor case that lead to burning away of the thrust reverser and translating cowl and subsequent fire damage to the engine pylon. The actions specified in this AD are intended to prevent burn through of the combustor case due to combustion liner cracking, which can result in an engine fire and damage to the aircraft.

Final rule; request for comments.

2000-03-07 ROLLS-ROYCE, plc: Amendment 39-11565. Docket 2000-NE-01-AD.
Applicability: Rolls-Royce plc (R-R) RB211-524H-36 series turbofan engines installed on but not limited to Boeing 767 series airplanes.
NOTE 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
Compliance: Required as indicated, unless accomplished previously.
To prevent burn through of the combustor case due to combustor liner cracking, which can result in an engine fire and damage to the aircraft, accomplish the following:
Installation of Improved Combustion Liner
(a) Prior to further flight, install an improved combustion liner with a strengthened head and improved heat shields, in accordance with the Accomplishment Instructions of R-R Service Bulletin (SB) No. RB.211-72-9764, Revision 3, dated January 16, 1998.
Alternative Methods of Compliance
(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Engine Certification Office. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office.
NOTE 2: Information concerning the existence of approved alternativemethods of compliance with this AD, if any, may be obtained from the Engine Certification Office.
No Ferry Flights
(c) Special flight permits will not be issued.
Incorporation by Reference
(d) The actions required by this AD shall be performed in accordance with the following R-R SB:

Document No.
Pages
Revision
Date
RB.211-72-9764
1
3
January 16, 1998

2
Original
August 20, 1993

3-6
3
January 16, 1998

7-10
Original
August 20, 1993

11
3
January 16, 1998

12-30
Original
August 20, 1993

Total pages: 30

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Rolls-Royce plc, PO Box 31, Derby, England; telephone: International Access Code 011, Country Code 44, 1332-249428, fax International Access Code 011, Country Code 44, 1332-249223. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.
(e) This amendment becomes effective on March 2, 2000.

The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom (UK), recently notified the Federal Aviation Administration (FAA) that an unsafe condition may exist on Rolls-Royce plc (R-R) RB211-524H-36 series turbofan engines. The CAA received a report of burn through of a combustor case that lead to burning away of the thrust reverser and translating cowl and subsequent fire damage to the engine pylon. The investigation revealed that front combustion liner diffuser case bleed struts and front section inner and outer liners demonstrate cracking after extended use. Additionally, combustion liners have exhibited burning of the heat shield inner ramp corners. This condition, if not corrected, could result in burn through of the combustor case due to combustion liner cracking, which can result in an engine fire and damage to the aircraft.
Service Information
R-R has issued Service Bulletin (SB) No. RB.211-72-9764, Revision 3, dated January 16, 1998, that specifies procedures for installing improved combustion liners with a strengthened head and improved heat shields. The CAA classified this SB as mandatory and issued airworthiness directive (AD) 009-01-98 in order to assure the airworthiness of these engines in the UK.

Bilateral Airworthiness Agreement
This engine model is manufactured in the UK and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the CAA has kept the FAA informed of the situation described above. The FAA has examined the findings of the CAA, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.
Required Actions
Since an unsafe condition has been identifiedthat is likely to exist or develop on other engines of the same type design, the AD requires, prior to entry into service, installing an improved combustion liner with a strengthened head and improved heat shields. At the present time, there are no affected engines installed on aircraft of US registry. Also, the CAA has advised the FAA that all engines in the active fleet have had the improved combustor liner installed. However, some spare engines may not have had the improved combustion liner installed. The actions would be required to be accomplished in accordance with the SB described previously.
Immediate Adoption
There are currently no domestic operators of this engine model. Accordingly, a situation exists that requires the immediate adoption of this regulation. Notice and opportunity for prior public comment hereon are impracticable, and good cause exists for making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.
Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted willbe available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2000-NE-01-AD." The postcard will be date stamped and returned to the commenter.
Regulatory Impact
The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order (EO) 13132.
The FAA has determined that this regulationis an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under EO 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES. List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.