[Federal Register Volume 61, Number 197 (Wednesday, October 9, 1996)]
[Rules and Regulations]
[Pages 52876-52877]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-25168]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-ANE-68; Amendment 39-9743; AD 96-18-17]
RIN 2120-AA64


Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and 
-5 Auxiliary Power Units

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to AlliedSignal Inc. (formerly Garrett) TSCP700-4B, -4E, and 
-5 auxiliary power units (APUs), that requires removal from service of 
certain high pressure turbine (HPT) disks identified by serial number, 
and replacement with serviceable parts. This amendment is prompted by 
the discovery of a material defect in certain HPT disk forgings that 
may result in HPT disk rupture prior to reaching the disk cyclic life 
limit. The actions specified by this AD are intended to prevent an HPT 
disk rupture.

DATES: Effective December 9, 1996.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of December 9, 1996.

ADDRESSES: The service information referenced in this AD may be 
obtained from AlliedSignal Engines, P.O. Box 52181, Phoenix, AZ 85072-
2181; telephone (800) 338-3378, fax (602) 231-4402. This information 
may be examined at the Federal Aviation Administration (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: Robert Baitoo, Aerospace Engineer, Los 
Angeles Aircraft Certification Office, FAA, Transport Airplane 
Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone 
(310) 627-5245; fax (310) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to AlliedSignal Inc. (formerly 
Garrett) Models TSCP700-4B, -4E, and -5 auxiliary power units (APUs) 
was published in the Federal Register on March 26, 1996 (61 FR 13113). 
That action proposed to require removal from service of certain high 
pressure turbine (HPT) disks identified by serial number, and 
replacement with serviceable parts, prior to accumulating 7,500 cycles 
since new (CSN), or 3 years after the effective date of this AD, 
whichever occurs first. The actions are required to be accomplished in 
accordance with AlliedSignal Aerospace Service Bulletin (SB) No. 
TSCP700-49-A7168, dated November 7, 1995.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    Four commenters support the rule as proposed.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.
    There are approximately 31 APUs of the affected design in the 
worldwide fleet. The FAA estimates that 20 APUs installed on aircraft 
of U.S. registry will be affected by this AD, that it will take no 
additional work hours if the disk is replaced during overhaul. The 
manufacturer has advised the FAA that they will supply required parts 
at no charge to the operator. The FAA has therefore determined that 
this AD will impose no additional cost on U.S. operators.
    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

[[Page 52877]]

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.
    For the reasons discussed above, I certify that this action (1) Is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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:

96-18-17  AlliedSignal Inc.: Amendment 39-9743. Docket 95-ANE-68.

    Applicability: AlliedSignal Inc. (formerly Garrett) Models 
TSCP700-4B, -4E, and -5 auxiliary power units (APUs), with high 
pressure turbine (HPT) disks identified by serial number in 
AlliedSignal Aerospace Service Bulletin (SB) No. TSCP700-49-A7168, 
dated November 7, 1995. These APUs are installed on, but not limited 
to, McDonnell Douglas DC-10, KC-10 (military), and MD-11 series, and 
Airbus A300 series aircraft.

    Note: This airworthiness directive (AD) applies to each APU 
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 APUs 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 (d) 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 an HPT disk rupture, accomplish the following:
    (a) Prior to accumulating 7,500 cycles since new (CSN), or 3 
years after the effective date of this AD, whichever occurs first, 
remove from service affected HPT disks and replace with a 
serviceable part.
    (b) The definition of a disk cycle may be found in the 
applicable AlliedSignal Inc. APU Component Maintenance Manual.
    (c) Auxiliary power unit maintenance records may be used to 
determine if the HPT disk installed in the APU has a serial number 
listed in AlliedSignal Aerospace SB No. TSCP700-49-A7168, dated 
November 7, 1995.
    (d) 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, Los Angeles Aircraft Certification 
Office. The request should be forwarded through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, Los Angeles Aircraft Certification Office.

    Note: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Los Angeles Aircraft Certification 
Office.

    (e) 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.
    (f) The actions required by this AD shall be done in accordance 
with the following AlliedSignal Aerospace SB:

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             Document No.               Pages             Date          
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TSCP700-49-A7168.....................     1-8  Nov. 7, 1995.            
Total Pages: 8.                                                         
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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 Engines, P.O. Box 
52181, Phoenix, AZ 85072-2181; telephone (800) 338-3378, fax (602) 
231-4402. 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.
    (g) This amendment becomes effective on December 9, 1996.

    Issued in Burlington, Massachusetts, on September 20, 1996.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 96-25168 Filed 10-8-96; 8:45 am]
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