Airworthiness directives: Royce GmbH,

[Federal Register: February 24, 1999 (Volume 64, Number 36)]

[Rules and Regulations]

[Page 9056-9058]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr24fe99-2]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-74-AD; Amendment 39-11050; AD 98-24-03]

RIN 2120-AA64

Airworthiness Directives; BMW Rolls-Royce GmbH Models BR700- 710A1-10 and BR700-710A2-20 Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule, request for comments.

SUMMARY: This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-24-03 that was sent previously to all known U.S. owners and operators of BMW Rolls-Royce GmbH (BRR) Models BR700-710A1-10 and BR700-710A2-20 turbofan engines by individual letters. This AD requires repetitive visual inspections of the fairing and fasteners for correct installation and damage, and verification that the engine core fairing fasteners are torqued to the higher torque value. This amendment is prompted by a report of an engine compressor core fairing failure during engine ground runs. The actions specified by this AD are intended to prevent engine compressor or combustion core fairing detachment and damage to the engine bypass duct, resulting in engine failure and damage to the aircraft.

DATES: Effective March 11, 1999, to all persons except those persons to whom it was made immediately effective by priority letter AD 98-24-03, issued on November 12, 1998, which contained the requirements of this amendment.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of March 11, 1999.

Comments for inclusion in the Rules Docket must be received on or before April 26, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, Attention: Rules Docket No. 98-ANE-74-AD, 12 New England Executive Park, Burlington, MA 01803-5299. Comments may also be sent via the Internet using the following address: ``9-ad- engineprop@faa.gov''. Comments sent via the Internet must contain the docket number in the subject line.

The applicable service information may be obtained from BMW Rolls- Royce GmbH, Eschenweg 11, D-15827 Dahlewitz, Germany; telephone 011-49- 33-7086-1883; fax 011-49-33-7086-3276. This information may be examined 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.

FOR FURTHER INFORMATION CONTACT: Diane Cook, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (781) 238- 7133, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: On November 12, 1998, the Federal Aviation Administration (FAA) issued priority letter airworthiness directive (AD) 98-24-03, applicable to BMW Rolls-Royce GmbH (BRR) Models BR700- 710A1-10 and BR700-710A2-20 turbofan engines, which requires visual inspections of the fairing and fasteners to ensure proper installation and for cracks or damage, and if cracked or damaged, replacement with serviceable parts, and also requires that the engine core fairing fasteners be torqued to a higher torque value. That action was prompted by a report of an engine compressor core fairing failure during engine ground runs on a BRR Model BR700-710A1-10 turbofan engine installed on a Gulfstream G-V model aircraft. Preliminary investigation indicates that the upper right compressor core fairing became detached and lodged in the engine bypass duct. The engine bypass duct was substantially damaged, resulting in engine removal. Following the event, additional in-field engine inspections of the compressor and combustion core fairings found some engine core fairing fasteners that were cracked, loose, not engaged, or no longer engageable.

The FAA received a comment to the Priority Letter AD recommending that

[[Page 9057]]

the language of Paragraph (a) in the compliance section be changed to clarify the intent. The commenter expressed concern that Paragraph (a) may be interpreted as requiring the removal and disassembly of the fairing and fasteners in order to visually inspect for cracks. The FAA disagrees. The language in Paragraph (a) is adequate without adding clarification. The intent of this paragraph not to remove or disassemble the fairings or fasteners but to visually inspect the fairings and fasteners for correct installation. Any damage or cracked hardware found during this visual inspection should be replaced.

Although the investigation continues, the FAA has determined that if this event occurred during flight, the damaged bypass duct could be potentially hazardous to the aircraft. This condition, if not corrected, could result in engine compressor or combustion core fairing detachment and damage to the engine bypass duct, resulting in engine failure and damage to the aircraft.

The FAA has reviewed and approved the technical contents of BRR Service Bulletin (SB) BR700-72-900062, Revision 2, dated November 3, 1998, that describes visual inspections to ensure proper installation of the engine compressor and combustion core fairings (also referred to as the engine core fairing) and increases the torque limits for the fairing fasteners.

Since the unsafe condition described is likely to exist or develop on other engines of the same type design, the FAA issued priority letter AD 98-24-03 to prevent engine failure and damage to the aircraft. The AD requires, prior to further flight, and thereafter at 50 hours time in service (TIS) intervals, visual inspection of the fairing and fasteners for correct installation and for cracks and damage, and verification that the engine core fairing fasteners are torqued to the higher torque value. These actions are required to be accomplished in accordance with the SB described previously.

Since it was found that immediate corrective action was required, notice and opportunity for prior public comment thereon were impracticable and contrary to the public interest, and good cause existed to make the AD effective immediately by individual letters issued on November 12, 1998, to all known U.S. owners and operators of BRR Models BR700-710A1-10 and BR700-710A2-20 turbofan engines. These conditions still exist, and the AD is hereby published in the Federal Register as an amendment to Section 39.13 of part 39 of the Federal Aviation Regulations (14 CFR part 39) to make it effective to all persons.

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 in triplicate 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 will be 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 filedin 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 98-ANE-74-AD.'' The postcard will be date stamped and returned to the commenter.

The regulations adopted herein will 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a ``significant regulatory action'' under Executive Order 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.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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:

   98-24-03 BMW Rolls-Royce GmbH: Amendment 39-11050. Docket 98-ANE- 74-AD.

   Applicability: BMW Rolls-Royce GmbH (BRR) Model BR700-710A1-10 and BR700-710A2-20 turbofan engines installed on, but not limited to, Gulfstream Aerospace G-V and Bombardier BD-700-1A10 model 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 (c) 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 compressor and combustion core fairing detachment which could result in damage to the engine bypass duct, engine failure and damage to the aircraft, accomplish the following:

   (a) Prior to further flight, visually inspect the engine compressor and combustion core

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   fairings and fasteners to ensure correct installation and for cracks or damage, and if cracked or damaged, replace with serviceable parts. Torque all the fasteners to the increased torque value, in accordance with BRR Service Bulletin (SB) BR700-72-900062, Revision 1, dated October 29, 1998, or Revision 2, dated November 3, 1998.

   (b) Thereafter, at intervals not to exceed 50 hours time in service (TIS) since last inspection, visually inspect the engine compressor and combustion core fairings and fasteners to ensure correct installation and for cracks or damage and, if cracked or damaged, replace with serviceable parts. Torque all the fasteners to the increased torque value, in accordance with BRR SB BR700-72- 900062, Revision 2, dated November 3, 1998.

   (c) 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 alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Engine Certification Office.

   (d) The actions required by this AD shall be done in accordance with the following BRR SB:

   Document No.

   Pages Revision

   Date

   BR700-72-900062............................

   1-8

   2 November 3, 1998.

   Total pages: 8.

   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 BMW Rolls-Royce GmbH, Eschenweg 11, D-15827 Dahlewitz, Germany; telephone 011-49-33-7086-1883; fax 011-49-33-7086-3276. 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 March 11, 1999, to all persons except those persons to whom it was made immediately effective by priority letter AD 98-24-03, issued November 12, 1998, which contained the requirements of this amendment.

   Issued in Burlington, Massachusetts, on February 16, 1999. David A. Downey, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service.

   [FR Doc. 99-4368Filed2-23-99; 8:45 am]

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