[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: ``<a href="/cdn-cgi/l/email-protection#60594d01044d6a050e07090e0510120f10200601014e040f144e070f16">9-ad-
<span class="__cf_email__" data-cfemail="b2d7dcd5dbdcd7c2c0ddc2f2d4d3d39cd6ddc69cd5ddc4">[email protected]</span></a>''. 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:

----------------------------------------------------------------------------------------------------------------
            Document No.                     Pages               Revision                      Date             
----------------------------------------------------------------------------------------------------------------
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


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