[Federal Register Volume 62, Number 148 (Friday, August 1, 1997)]
[Rules and Regulations]
[Pages 41262-41265]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-20192]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-ANE-36; Amendment 39-10091; AD 97-05-11 R1]
RIN 2120-AA64
Airworthiness Directives; AlliedSignal Inc. ALF502 and LF507
Series Turbofan Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment revises an existing airworthiness directive
(AD), applicable to AlliedSignal Inc. ALF502 and LF507 series turbofan
engines, that currently requires initial and repetitive inspections of
the oil system chip detectors and oil filter bypass valve, and optional
installation of an improved oil filter bypass valve, to ensure the
[[Page 41263]]
integrity of the reduction gear system and overspeed protection system.
This amendment adds an initial inspection threshold for the oil
maintenance requirements that was inadvertently omitted from AD 97-05-
11, and makes editorial corrections. Paragraphs (b) through (f) of AD
97-05-11 have been rearranged in this AD to make these corrections.
This amendment is prompted by the inadvertent omission of the initial
inspection threshold. The actions specified by this AD are intended to
prevent No. 4 and 5 duplex bearing failure, which can result in a Stage
4 low pressure turbine (LPT) rotor failure, an uncontained engine
failure, and damage to the aircraft.
DATES: Effective August 18, 1997.
The incorporation by reference of certain publications listed in
the regulations was approved by the Director of the Federal Register as
of April 16, 1997.
Comments for inclusion in the Rules Docket must be received on or
before September 30, 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. 96-ANE-36, 12 New England
Executive Park, Burlington, MA 01803-5299. Comments may also be sent
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain
the docket number in the subject line.
The service information referenced in this AD may be obtained from
AlliedSignal Aerospace, Attn: Data Distribution, M/S 64-3/2101-201,
P.O. Box 29003, Phoenix, AZ 85038-9003; telephone (602) 365-2493, fax
(602) 365-5577. This information may be examined at the FAA, New
England Region, Office of the Assistant Chief 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: Raymond Vakili, Aerospace Engineer,
Los Angeles Aircraft Certification Office, FAA, Transport Airplane
Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone
(562) 627-5262; fax (562) 627-5210.
SUPPLEMENTARY INFORMATION: On July 17, 1987, the Federal Aviation
Administration (FAA) issued airworthiness directive (AD) 87-06-52 R1,
Amendment 39-5688 (52 FR 31979, August 25, 1987), applicable to
AlliedSignal Inc. (formerly Avco Lycoming Textron) ALF502R series
turbofan engines, to require initial and repetitive inspections of the
oil system chip detectors and oil filter bypass valve, and optional
installation of an improved oil filter bypass valve, to ensure the
integrity of the reduction gear system and overspeed protection system.
The optional installation of the improved oil filter bypass valve
provides terminating action for the repetitive oil filter bypass valve
spring compression test also required by AD 87-06-52 R1. That action
was prompted by reports of power turbine (PT) overspeed and uncontained
PT blade failure resulting from reduction gear system decouple and
inaccurate PT overspeed signal generation. That condition, if not
corrected, could result in No. 4 and 5 duplex bearing failure, which
can result in a Stage 4 low pressure turbine (LPT) rotor failure, an
uncontained engine failure, and damage to the aircraft.
Since the issuance of AD 87-06-52 R1, the FAA has received reports
of four additional failures of the Stage 4 low pressure turbine (LPT)
rotor on AlliedSignal Inc. ALF502 series turbofan engines. The LPT
failures were caused by failure of the No. 4 and 5 duplex bearing,
causing bearing seizure and LPT shaft separation between the two
bearings forward of the Stage 4 LPT rotor. In one incident the Stage 4
LPT shaft separation caused an uncontained rotor failure.
On March 27, 1997, the FAA issued AD 97-05-11, Amendment 39-9955
(62 FR 15378, April 1, 1997), to supersede AD 87-06-52 R1 to require
more stringent oil system inspection requirements, including inspection
of the full flow chip detector, oil filter impending bypass button, oil
acid number, oil color, and oil quantity.
Since the issuance of AD 97-05-11, the FAA has determined that the
initial inspection threshold for the oil maintenance requirements were
inadvertently omitted. This amendment adds the initial inspection
threshold for the oil maintenance requirements and corrects the service
bulletin numbers referenced in the AD.
The FAA has reviewed and approved the technical contents of
AlliedSignal Inc. Service Bulletins (SBs): No. ALF502L 79-0171,
Revision 1, dated November 27, 1996; No. LF507-1F 79-5, Revision 1,
dated November 27, 1996; No. LF507-1H 79-5, Revision 1, dated November
27, 1996; and No. ALF502R 79-9, Revision 1, dated November 27, 1996.
These SBs describe procedures for oil system inspection. In addition,
FAA has reviewed and approved the technical content of Textron Lycoming
SB No. ALF 502R-79-0162, Revision 2, dated September 8, 1987, to ensure
that portions of the accomplishment instructions paragraph of this SB
continues to provide the terminating action for the oil filter bypass
valve compression spring test. Also, the FAA has reviewed and approved
the technical contents of Avco Lycoming Textron SB No. ALF 502R-72-
0160, Revision 2, dated May 26, 1987, and Revision 1, dated March 23,
1987, that describe procedures for chip detector inspections. Finally,
the FAA has reviewed and approved the technical contents of Avco
Lycoming Textron SB No. ALF 502R-79-0162, Revision 1, dated May 26,
1987, and Original, dated March 23, 1987, that describe procedures of
inspection of the oil filter bypass valve.
Since an unsafe condition has been identified that is likely to
exist or develop on other engines of this same type design, this AD
revises AD 97-05-11 to add the initial inspection threshold for the oil
maintenance requirements which was inadvertently omitted from AD 97-05-
11, Amendment 39-9955, paragraphs (b) through (e), and corrects the
editorial errors in paragraph (a)(1) and (c). Paragraphs (b) through
(f) are re-arranged as a result of these corrections. The actions are
required to be accomplished in accordance with the SBs described
previously.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that 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
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.
[[Page 41264]]
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 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 96-ANE-36.'' 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 removing Amendment 39-9955 (62 FR
15378, April 1, 1997) and by adding a new airworthiness directive,
Amendment 39-10091, to read as follows:
97-05-11 R1 AlliedSignal Inc.: Amendment 39-10091. Docket 96-ANE-36.
Revises AD 97-05-11, Amendment 39-9955.
Applicability: AlliedSignal Inc. and Textron Lycoming Model
ALF502 and LF507 series turbofan engines, installed on but not
limited to British Aerospace BAe146-100A, BAe146-200A, BAe146-300A,
AVRO 146-RJ70A, AVRO 146-RJ85A, AVRO 146-RJ100A, and Canadair Model
CL-600-1A11 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 (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 No. 4 and 5 duplex bearing failure, which can result
in a Stage 4 low pressure turbine (LPT) rotor failure, an
uncontained engine failure, and damage to the aircraft, accomplish
the following:
(a) For ALF502R series engines equipped with oil filter bypass
valve, part number (P/N) 2-303-432-01, accomplish the following:
(1) Inspect the engine oil filter bypass valve for leakage
within the next 25 engine hours or 25 flights in service, whichever
occurs first, from the effective date of this AD, in accordance with
Avco Lycoming Textron Service Bulletin (SB) No. ALF 502R-79-0162,
Original, dated March 23, 1987, or Revision 1, dated May 26, 1987.
Prior to further flight, remove from service oil filters exhibiting
any leakage and replace with serviceable parts.
(2) Thereafter, inspect the oil filter bypass valve for any
leakage in accordance with Avco Lycoming Textron SB No. ALF 502R-79-
0162, Original, dated March 23, 1987, or Revision 1, dated May 26,
1987, at intervals not to exceed 50 engine hours or 50 flights in
service since last inspection, whichever occurs first, and at the
same time accomplish the following:
(i) Visually inspect the following engine chip detectors for
metal contamination:
(A) For engines with a full flow chip detector installed,
inspect the full flow chip detector.
(B) For engines without a full flow chip detector installed,
inspect the chip detectors located in the accessory gearbox, Number
2 bearing scavenge line, and Number 4/5 bearing scavenge line.
(ii) For engines with engine chip detectors exhibiting Condition
3, or Condition 2, or Condition 1 where the oil filter bypass
indicator is extended, prior to further flight, remove oil filter
bypass valves exhibiting any leakage and replace with a serviceable
part.
Note 2: Chip detector conditions are described in Avco Lycoming
Textron SB No. ALF502R-72-0160, Revision 1, dated March 23, 1987,
Figures 1, 2 and 3.
(3) At the next engine shop visit, or within 2,500 engine hours
after the effective date of this AD, whichever occurs first, conduct
the oil filter bypass valve spring compression force check, in
accordance with Avco Lycoming Textron SB No. ALF 502R-79-0162,
Original, dated March 23, 1987. Oil filter bypass valves which do
not comply with the spring compression force limits contained in
Avco Lycoming Textron SB No. ALF 502R-79-0162, Original, dated March
23, 1987, must be removed and replaced with oil filter bypass valve,
P/N 2-303-432-02. Replacement of oil filter bypass valve, P/N 2-303-
432-01, with the improved oil filter bypass valve, P/N 2-303-432-02,
constitutes terminating action for the inspection requirements of
paragraphs (a)(1) and (a)(2) of this AD.
(4) For the purpose of this AD, an engine shop visit is defined
as engine maintenance that entails any of the following:
(i) Separation of a major engine flange (lettered or numbered)
other than flanges mating with major sections of the nacelle
reverser. Separation of flanges purely for purposes of shipment,
without subsequent internal maintenance, is not a ``shop visit.''
(ii) Removal of a disk, hub, or spool.
(iii) Removal of the fuel nozzles.
(b) For ALF502R, ALF502L, LF507-1F, and LF507-1H series engines,
equipped with the No. 4 and 5 duplex bearing assembly numbers 2-141-
930-01, 2-141-930-02, or 2-141-930-03, perform the repetitive oil
system maintenance and inspections in accordance with the intervals
and procedures described in the Accomplishment Instructions
paragraphs of the applicable AlliedSignal Inc. SBs referenced in
paragraphs (b)(1), (b)(2), (b)(3), and (b)(4) of this AD, within the
next 25 engine hours or 25 flights in service, whichever occurs
first, from the effective date of this AD.
(1) For ALF502R series engines, in accordance with AlliedSignal
Inc. SB No. ALF502R 79-9, Revision 1, dated November 27, 1996.
(2) For ALF502L series engines, in accordance with AlliedSignal
Inc. SB No. ALF502L 79-0171, Revision 1, dated November 27, 1996.
(3) For LF507-1F series engines, in accordance with AlliedSignal
Inc. SB No. LF507-1F-79-5, Revision 1, dated November 27, 1996.
[[Page 41265]]
(4) For LF507-1H series engines, in accordance with AlliedSignal
SB No. LF507-1H-79-5, Revision 1, dated November 27, 1996.
(c) An alternative method of compliance or adjustment of the
initial compliance time that provides an acceptable level of safety
may be used if approved by the Manager, Los Angeles Aircraft
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, Los Angeles Aircraft
Certification Office.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles Aircraft Certification Office.
(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 aircraft to a location where
the requirements of this AD can be accomplished.
(e) The actions required by this AD shall be done in accordance
with the accomplishment instructions paragraphs of the following
documents:
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Document No. Pages Revision Date
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Avco Lycoming Textron SB No. ALF 1-7 2 May 26, 1987.
502R-72-0160.
Total Pages: 7.
Avco Lycoming Textron SB No. ALF 1-7 1 March 23, 1987.
502R-72-0160.
Total Pages: 7.
Avco Lycoming Textron SB No. ALF 1-5 2 September 8, 1987.
502R-79-0162.
Total Pages: 5.
Avco Lycoming Textron SB No. ALF 1-4 1 May 26, 1987.
502R-79-0162.
Total Pages: 4.
Avco Lycoming Textron SB No. ALF 1-6 Original March 23, 1987.
502R-79-0162.
Total Pages: 6.
AlliedSignal Inc. SB No. ALF502R 79- 1 1 November 27, 1996.
9
2 Original June 29, 1995.
3-7 1 November 27, 1996.
8 Original June 29, 1995.
9-12 1 November 27, 1996.
13,14 Original June 29, 1995.
Total Pages: 14.
AlliedSignal Inc. SB No. LF507-1F 79- 1 1 November 27, 1996.
5.
2 Original June 29, 1995.
3-7 1 November 27, 1996.
8 Original June 29, 1995.
9-12 1 November 27, 1996.
13,14 Original June 29, 1995.
Total Pages: 14.
AlliedSignal Inc. SB No. LF507-1H 79- 1 1 November 27, 1996.
5.
2 Original June 29, 1995.
3-7 1 November 27, 1996.
8 Original June 29, 1995.
9-12 1 November 27, 1996.
13,14 Original June 29, 1995.
Total Pages: 14.
AlliedSignal Inc. SB ALF502L 79-0171 1 1 November 27, 1996.
2 Original November 3, 1995.
3-7 1 November 27, 1996.
8 Original November 3, 1995.
9-12 1 November 27, 1996.
13,14 Original November 3, 1995.
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Total Pages: 14
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 AlliedSignal Aerospace, Attn: Data
Distribution, M/S 64-3/2101-201, P.O. Box 29003, Phoenix, AZ 85038-
9003; telephone (602) 365-2493, fax (602) 365-5577. Copies may be
inspected at the FAA, New England Region, Office of the Assistant Chief
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.
(f) This amendment becomes effective on August 18, 1997.
Issued in Burlington, Massachusetts, on July 23, 1997.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 97-20192 Filed 7-31-97; 8:45 am]
BILLING CODE 4910-13-U