[Federal Register Volume 61, Number 220 (Wednesday, November 13, 1996)]
[Proposed Rules]
[Pages 58147-58148]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-28983]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-ANE-56]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc RB.211-524 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to Rolls-Royce plc RB.211-524 series 
turbofan engines. This proposal would require initial and repetitive 
borescope inspections of the head section and meterpanel assembly of 
the combustion liner, and replacement, if necessary, with serviceable 
parts. In addition, this AD would propose an optional installation of a 
front combustion liner with a strengthened head section as a 
terminating action to the inspection requirements. This proposal is 
prompted by reports of engine fires due to premature engine combustor 
distress. The actions specified by the proposed AD are intended to 
prevent engine combustor liner deterioration due to thermal fatigue, 
which can result in combustor liner and case burn-through and engine 
fire.

DATES: Comments must be received by January 13, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-ANE-56, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location between 8:00 a.m. and 4:30 p.m., Monday through Friday, 
except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Rolls-Royce North America, Inc., 2001 South Tibbs Ave., 
Indianapolis, IN 46241; telephone (317) 230-3995, fax (317) 230-4743. 
This information may be examined at the FAA, New England Region, Office 
of the Assistant Chief Counsel, 12 New England Executive Park, 
Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Eugene Triozzi, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (617) 
238-7148, fax (617) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal 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 95-ANE-56.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, New England Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 95-ANE-56, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, recently notified the Federal 
Aviation Administration (FAA) that an unsafe condition may exist on 
Rolls-Royce plc (R-R) RB.211-524 series turbofan engines. The CAA 
received three reports of engine fires during takeoff and climb. The 
investigation revealed that the engine combustor liners had 
deteriorated, due to thermal fatigue of either the head section or 
meterpanels. In addition, the CAA received reports of premature engine 
combustor distress found during routine borescope inspections. This 
condition, if not corrected, could result in engine combustor liner 
deterioration due to thermal fatigue, which can result in combustor 
liner and case burn-through and engine fire.
    Rolls-Royce plc has issued Service Bulletin (SB) No. RB.211-72-
B482, Revision 2, dated March 11, 1996, that specifies procedures for 
borescope inspections; and SB No. RB.211-72-9764, Revision 2, dated 
November 10, 1995, that specifies procedures for installing a front 
combustion liner with a strengthened head section manufactured of C263 
material. The CAA classified SB No. RB.211-72-B482, Revision 2, dated 
March 11, 1996, as mandatory and issued AD 005-07-95, dated March 11, 
1996, in order to assure the airworthiness of these engines in the 
United Kingdom.
    This engine model is manufactured in the United Kingdom 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.

[[Page 58148]]

    Since an unsafe condition has been identified that is likely to 
exist or develop on other engines of the same type design registered in 
the United States, the proposed AD would require initial and repetitive 
borescope inspections of the head section and meterpanel assembly of 
the combustion liner, and replacement, if necessary, with serviceable 
parts. In addition, this AD would propose an optional installation of a 
front combustion liner with a strengthened head section C263 material 
as a terminating action to the inspection requirements. The actions 
would be required to be accomplished in accordance with the SB's 
described previously.
    There are approximately 250 engines of the affected design in the 
worldwide fleet. There are currently no domestic operators of Rolls-
Royce plc RB.211-524G or -524H series turbofan engines. The FAA 
estimates that it would take approximately 8 work hours per engine to 
accomplish the proposed inspections, and that the average labor rate is 
$60 per work hour. Based on these figures, the cost impact per engine 
per inspection is estimated to be $480.
    The regulations proposed herein would not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that 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) if promulgated, 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. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

Rolls-Royce plc: Docket No. 95-ANE-56.

    Applicability: Rolls-Royce plc (R-R) Models RB.211-524G and -
524H turbofan engines that have not been modified in accordance with 
R-R Service Bulletin (SB) No. RB.211-72-9764, Revision 2, dated 
November 10, 1995, installed on but not limited to Boeing 747-400 
and 767-300 series aircraft.

    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 (d) 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 engine combustor liner deterioration due to 
thermal fatigue, which can result in combustor liner and case burn-
through and engine fire, accomplish the following:
    (a) Perform initial and repetitive borescope inspections of the 
engine combustor liner head section in accordance with the intervals 
listed in Section 1.C. Compliance (1), and the procedures described 
in Section 1.D. Action (1) of R-R SB No. RB.211-72-B482, Revision 2, 
dated March 11, 1996. Prior to further flight, remove combustors 
that do not meet the return to service criteria specified in Section 
1.E. Acceptance Limits of the SB and replace with serviceable parts.
    (b) Perform initial and repetitive borescope inspections of the 
meterpanel in accordance with the intervals listed in Section 1.C. 
Compliance (2), and the procedures described in Section 1.D. Action 
(2) of R-R SB No. RB.211-72-B482, Revision 2, dated March 11, 1996. 
Prior to further flight, remove combustors that do not meet the 
return to service criteria specified in Section 1.E. Acceptance 
Limits of the SB and replace with serviceable parts.
    (c) Installation of a front combustion liner with a strengthened 
head section in C263 material in accordance with R-R SB No. RB.211-
72-9764, Revision 2, dated November 10, 1995, constitutes 
terminating action to the inspection requirements of this AD.
    (d) 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. The 
request should be forwarded 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 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Engine Certification Office.

    (e) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the aircraft to a location where 
the requirements of this AD can be accomplished.

    Issued in Burlington, Massachusetts, on October 30, 1996.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 96-28983 Filed 11-12-96; 8:45 am]
BILLING CODE 4910-13-P