[Federal Register Volume 64, Number 158 (Tuesday, August 17, 1999)]
[Proposed Rules]
[Pages 44666-44667]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-21332]



[[Page 44666]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-74-AD]


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise an existing airworthiness 
directive (AD) applicable to BMW Rolls-Royce GmbH (BRR) Models BR700-
710A1-10 and BR700-710A2-20 turbofan engines. The existing AD currently 
requires initial and repetitive visual inspections of the engine 
compressor and combustion core fairings (also referred to as the engine 
core fairings) and fasteners for correct installation and damage, and 
verification that the engine core fairing fasteners are torqued to a 
higher torque value. This action would increase the repetitive 
inspection interval to 150 hours time-in-service (TIS) following an 
initial inspection and follow-on inspection at the current 50 hours TIS 
interval. This action also would require an initial inspection and 
follow-on inspection at a 50 hours TIS interval following any engine 
core fairing or fastener removal, repair, or replacement. Repair of 
engine core fairings has been added as an alternate to engine core 
fairing replacement, and an inspection for loose engine core fairing(s) 
has been included to verify correct installation on the engine. This 
proposal is prompted by results of repetitive inspections that indicate 
that the inspection interval can be increased safely. The actions 
specified by the proposed 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 airplane.

DATES: Comments must be received by September 16, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
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-ane-
[email protected]''. Comments sent via the Internet must contain the 
docket number in the subject line. 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 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.

FOR FURTHER INFORMATION CONTACT: Keith Mead, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7744, fax (781) 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 98-ANE-74-AD.'' 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 Regional Counsel, 
Attention: Rules Docket No. 98-ANE-74-AD, 12 New England Executive 
Park, Burlington, MA 01803-5299.

Discussion

    On February 16, 1999, the Federal Aviation Administration (FAA) 
issued airworthiness directive (AD) 98-24-03, Amendment 39-11050 (64 FR 
9056, February 24, 1999), following a priority letter AD issued 
November 12, 1998, applicable to BMW Rolls-Royce GmbH (BRR) Models 
BR700-710A1-10 and BR700-710A2-20 turbofan engines. That AD requires 
initial and repetitive visual inspections of the engine compressor and 
combustion core fairings (also referred to as the engine core fairings) 
and fasteners for correct installation and damage, and verification 
that the engine core fairing fasteners are torqued to the 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 aircraft. That 
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 airplane.
    Since the issuance of that AD, the Luftfahrt-Bundesamt (LBA), which 
is the airworthiness authority for Germany, has notified the FAA that 
they have determined, based on ongoing investigations and results of 
successful repetitive inspections, that the inspection interval can be 
safely increased. They also determined that if an engine core fairing 
was removed, an initial inspection and follow-on inspection at the 
current 50 hour TIS interval would be required to insure correct 
installation, before the 150 hour repetitive time-in-service (TIS) 
interval is permitted. They also instituted an inspection requirement 
for loose engine core fairings to verify proper installation and 
allowed the use of repaired engine core fairings. The LBA issued AD 
1998-467/2 following publication of BRR Service Bulletin (SB) No. 
BR700-72-900062, Revision 3, dated March 24,1999, that increases the 
repetitive inspection intervals.
    This engine model is manufactured in Germany 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 LBA has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
LBA, reviewed all available information, and

[[Page 44667]]

determined that AD action is necessary for products of this type design 
that are certificated for operation in the United States.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would revise AD 98-24-03 to increase the repetitive 
inspection interval to 150 hours time-in-service (TIS) following a 
successful initial inspection and one follow-on inspection at the 
current 50 hours TIS inspection interval. Any engine core fairings or 
fasteners that have been removed, repaired, or replaced will require an 
initial inspection before flight and one follow-on inspection at the 50 
hours TIS interval before the 150 hour TIS inspection interval is 
allowed.
    There exists no adverse economic impact because this proposed rule 
only increases the repetitive inspection interval.
    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 removing Amendment 39-11050 (64 FR 
9056, February 24, 1999), and by adding a new airworthiness directive, 
to read as follows:

BMW Rolls-Royce GmbH: Docket No. 98-ANE-74-AD. Revises AD 98-24-03, 
Amendment 39-11050.

    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 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 (e) 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 (also 
referred to as the engine 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 core 
fairings and fasteners to ensure correct installation and for 
cracks, loose fairings, or fasteners, and if loose, cracked, 
damaged, or improperly installed, repair or 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, or 
Revision 3, dated March 24, 1999.
    (b) Thereafter, except as provided in paragraphs (c) or (d) of 
this AD, at intervals not to exceed 50 hours time-in-service (TIS) 
since last inspection, visually inspect the engine core fairings and 
fasteners for cracks, loose fairings, or fasteners, and, if loose, 
cracked, or damaged, repair or 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, or Revision 3, dated March 24, 1999.
    (c) Following an initial inspection in accordance with paragraph 
(a) of this AD, and one follow-on inspection in accordance with 
paragraph (b), if both inspections found no cracks, damage, loose 
fairings or fasteners the repetitive inspection interval may be 
increased to 150 hours TIS since last inspection in accordance with 
the procedures described in paragraph (b) of this AD.
    (d) Reinspection and retorquing prior to further flight is 
required in accordance with paragraph (a) of this AD, following any 
engine core fairing or fastener which has been removed, repaired or 
replaced. One successful follow-on inspection and retorque in 
accordance with paragraph (b) of this AD must be accomplished before 
the repetitive 150 hour TIS inspection interval described in 
paragraph (c) of this AD is permitted.
    (e) 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.

    Issued in Burlington, Massachusetts, on August 11, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 99-21332 Filed 8-16-99; 8:45 am]
BILLING CODE 4910-13-U