[Federal Register Volume 62, Number 58 (Wednesday, March 26, 1997)]
[Proposed Rules]
[Pages 14363-14365]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-7682]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 97-NM-06-AD]
RIN 2120-AA64
Airworthiness Directives; Lockheed Model L-1011 Series Airplanes
Equipped With Rolls-Royce Model RB.211-524 Series Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to certain Lockheed Model L-
1011 series airplanes, that currently requires several modifications of
the engine high speed gearboxes. This action would require that a new
modification be installed in lieu of one of those previously required.
This proposal is prompted by a report indicating that one of the
currently required modifications is not completely effective because it
can create interference problems between the fireloop and a fuel line.
The actions specified by the proposed AD are intended to reduce the
possibility of a fire in the high speed gear boxes, and to ensure that
any fire which may occur is readily detected by the flight crew.
DATES: Comments must be received by May 5, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-06-AD, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056. Comments may be inspected at this location
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal
holidays.
The service information referenced in the proposed rule may be
obtained from Lockheed Aeronautical Systems Support Company, Field
Support Department, Dept. 693, Zone 0755, 2251 Lake Park Drive, Smyrna,
Georgia 30080; and Rolls-Royce plc, Technical Publications Department,
P.O. Box 17, Parkside, Coventry CV1 2LZ, England. This information may
be examined at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Thomas Peters, Aerospace Engineer,
Systems and Flight Test Branch, ACE-116A, FAA, Atlanta Aircraft
Certification Office, Small Airplane Directorate, Campus Building, 1701
Columbia Avenue, Suite 2-160, College Park, Georgia 30337-2748;
telephone (404) 305-7367; fax (404) 305-7348.
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 shall 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.
[[Page 14364]]
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 97-NM-06-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, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 97-NM-06-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On February 1, 1994, the FAA issued AD 94-03-10, amendment 39-8817
(59 FR 6535, February 11, 1994), applicable to certain Lockheed Model
L-1011 series airplanes, to require several modifications of the engine
high speed gear boxes:
1. Installation of an additional fire detection system on the high
speed gearbox on the number 1, 2, and 3 engines;
2. Installation of a new vent tube in the gear compartment of the
high speed gearbox on the number 1, 2, and 3 engines; and
3. Modification of the breather duct of the high speed gearbox on
the number 2 engine.
That AD was prompted by a report of an oil fire that occurred in
the engine high speed gearbox on a Rolls Royce RB211-524 series on one
airplane. The fire burned a hole through the gearbox in the vicinity of
the breather rotor. Investigation revealed that the fire was caused by
problems associated with the failure of a roller bearing in the
gearbox. Failure of any of the roller bearings in the engine high speed
gearbox can lead to ignition of the gearbox oil. An internal gearbox
fire could eventually breach the gearbox, due to melting of the
magnesium in the gearbox housing, and could damage adjacent components.
The requirements of that AD are intended to reduce the possibility
of fire in the engine high speed gearbox, and to ensure that, if a fire
occurs, it is readily detected by the flight crew.
Actions Since Issuance of Previous Rule
Since the issuance of AD 94-03-10, the FAA has received a report
indicating that one operator, who had installed the required fire
detection system on its affected airplanes, identified an interference
problem between the fireloop (fire rail sensor assembly) and the
flexible fuel supply tube when the installation was completed. This
interference allows these two components to come into contact with each
other, which renders the modification less effective than intended in
minimizing the possibility of a fire in the engine high speed gearbox.
Explanation of Relevant Service Information
The FAA has reviewed and approved Lockheed Service Bulletin 093-26-
039, Revision 1, dated April 10, 1996, which describes procedures for
installing an additional fire detection loop in the number. 1, 2, and 3
high speed gearboxes on Rolls Royce RB.211-524 series engines. It also
describes new procedures for revising the routing of the fire detector
sensor assembly, with associated clipping changes to alleviate the lack
of clearance.
Explanation of Requirements of Proposed Rule
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 supersede AD 94-03-10. It would continue to require
installation of a new vent tube in the high speed gearbox on the number
1, 2, and 3 engines, and modification of the breather duct of the high
speed gearbox on the number 2 engine.
This proposed AD also would continue to require the installation of
an additional fire detection system on the high speed gearbox on the
number 1, 2, and 3 engines; however, it would require that the
installation be accomplished in accordance with the revised service
bulletin, described previously, which incorporates the new routing
procedures. This proposed requirement would mean that operators who
already have complied with the installation required by AD 94-03-10
must perform additional procedures relative to rerouting the
installation assembly.
Cost Impact
There are approximately 92 Lockheed Model L-1011 series airplanes
of the affected design in the worldwide fleet. The FAA estimates that
28 airplanes of U.S. registry would be affected by this proposed AD.
The installation of a new vent tube in the high speed gear box,
which is currently required by AD 94-03-10, takes approximately 3 work
hours to accomplish, at an average labor rate of $60 per work hour.
Required parts are estimated to cost $500 per airplane.
Based on these figures, the cost impact of this action on U.S.
operators is estimated to be $19,040, or $680 per airplane.
The modification of the breather duct on the high speed gearbox on
the number 2 engine, which is currently required by AD 94-03-10,
requires approximately 6 work hours to accomplish, at an average labor
rate of $60 per work hour. Required parts are estimated to cost $10,000
per airplane. Based on these figures, the cost impact of this action on
U.S. operators is estimated to be $290,080, or $10,360 per airplane.
The installation of the additional fire detecting loop in
accordance with the revised Lockheed service bulletin would require
approximately 9 work hours per airplane to accomplish, at an average
labor rate of $60 per work hour. If the airplane is equipped with a
Walter Kidde fire detection system, required parts are estimated to
cost $2,100 per airplane. If the airplane is equipped with a Graviner
fire detection system, required parts are estimated to cost $8,100 per
airplane. Based on these figures, the cost impact of this proposed
requirement on U.S. operators is estimated to be between $73,920 and
$241,920 for the fleet, or between $2,640 and $8,640 per airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the current or proposed
requirements of this AD action, and that no operator would accomplish
those actions in the future if this AD were not adopted. However, the
FAA has been advised that at least 19 airplanes of U.S. registry
already have been modified to incorporate the breather duct on the high
speed gearbox on the number 2 engine. Therefore, the future cost impact
of this proposed AD is reduced by at least $196,840.
Regulatory Impact
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
[[Page 14365]]
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 39-8817 (59 FR
6535, February 11, 1994), and by adding a new airworthiness directive
(AD), to read as follows:
LOCKHEED: Docket 97-NM-06-AD. Supersedes AD 94-03-10, Amendment 39-
8817.
Applicability: Model L-1011 series airplanes, equipped with
Rolls-Royce Model RB211-524 series engines; certificated in any
category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes 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 reduce the possibility of a fire in the engine high speed
gearbox, and to insure that, if a fire occurs, it is readily
detected by the flight crew, accomplish the following:
(a) Within 16,000 flight hours or 48 months after March 14,
1994, (the effective date of AD 94-03-10, amendment 39-8817),
whichever occurs first, accomplish both paragraphs (a)(1) and (a)(2)
of this AD:
(1) Install a new vent tube in the gear compartment of the high
speed gearbox on the number 1, number 2, and number 3 engines, in
accordance with Rolls-Royce Service Bulletin RB.211-72-4666,
Revision 4, dated May 16, 1986.
Note 2: Installation of a new vent tube prior to the effective
date of this AD in accordance with Rolls-Royce Service Bulletin
RB.211-72-4666, Revision 3, dated October 14, 1977, is considered
acceptable for compliance with this AD.
(2) Modify the breather duct of the high speed gearbox on the
number 2 engine in accordance with Lockheed Service Bulletin 093-71-
067, Revision 2, dated December 12, 1988.
Note 3: Modification of the breather duct prior to the effective
date of this AD in accordance with Lockheed Service Bullion 093-71-
067, Revision 1, dated April 1, 1986, is considered acceptable for
compliance with this AD.
(b) Install an additional fire detection system on the high
speed gearbox on the number 1, number 2, and number 3 engines in
accordance with paragraph (b)(1), (b)(2), or (b)(3) of this AD, as
applicable:
(1) For airplanes on which an additional fire detection system
has not been installed: Within 6,000 flight hours or 18 months after
the effective date of this AD, whichever occurs first, install the
system in accordance with Lockheed Service Bulletin 093-26-039,
Revision 1, dated April 10, 1996.
(2) For airplanes on which an additional fire detection system
has been installed prior to the effective date of this AD and in
accordance with Lockheed Service Bulletin 093-26-039, dated November
11, 1992: Within 6,000 flight hours or 18 months after the effective
date of this AD, whichever occurs first, modify the system in
accordance with Lockheed Service Bulletin 093-26-039, Revision 1,
dated April 10, 1996.
(3) For airplanes on which an additional fire detection system
has been installed prior to the effective date of this AD and in
accordance with Lockheed Service Bulletin 093-26-039, Revision 1,
dated April 10, 1996: No further action is required by this
paragraph.
(c)(1) 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, Atlanta Aircraft Certification
Office (ACO), FAA, Small Airplane Directorate. Operators shall
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Atlanta ACO.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Atlanta ACO.
(2) Alternative methods of compliance, approved previously in
accordance with AD 94-03-10, amendment 39-8817, are approved as
alternative methods of compliance with this AD.
(d) 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 airplane to a location where
the requirements of this AD can be accomplished.
Issued in Renton, Washington, on March 20, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-7682 Filed 3-25-97; 8:45 am]
BILLING CODE 4910-13-U