[Federal Register Volume 61, Number 250 (Friday, December 27, 1996)]
[Rules and Regulations]
[Pages 68141-68143]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-32181]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-ANE-27; Amendment 39-9855; AD 96-25-12]
RIN 2120-AA64


Airworthiness Directives; Sundstrand T-62T-40C Series Auxiliary 
Power Units

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to Sundstrand T-62T-40C series auxiliary power units 
(APUs). This action requires removal from service of certain compressor 
wheels in accordance with a drawdown schedule, and replacement with 
serviceable parts, and establishes a new cyclic life limit for the 
existing compressor wheels. This amendment is prompted by reports of 
compressor wheel ruptures. The actions specified in this AD are 
intended to prevent compressor wheel rupture, which could result in an 
uncontained APU failure and damage to the aircraft.

DATES: Effective January 13, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 13, 1997.
    Comments for inclusion in the Rules Docket must be received on or 
before February 25, 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-27, 12 New England 
Executive Park, Burlington, MA 01803-5299.
    The service information referenced in this AD may be obtained from 
Sundstrand Aerospace, 4400 Ruffin Rd., P.O. Box 85757, San Diego, CA 
92186-5757; telephone (619) 627-6303, fax (619) 627-6473. 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: 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: The Federal Aviation Administration (FAA) 
has received three reports of compressor wheels, installed on 
Sundstrand T-62T-40C series auxiliary power units (APUs), that ruptured 
prior to the published cyclic life limit. Of the three ruptures, two 
were uncontained. The investigation revealed that the compressor wheels 
ruptured due to low cycle fatigue. This condition, if not corrected, 
could result in compressor wheel rupture, which could result in an 
uncontained APU failure and damage to the aircraft.
    The FAA has reviewed and approved the technical contents of 
Sundstrand Aerospace Service Bulletin (SB) No. SB-T-62T-49-120, 
Revision 2, dated November 5, 1996, Revision 1, dated September 9, 
1996, and Original, dated July 22, 1996, that describe procedures for 
removal from service of certain compressor wheels in accordance with a 
drawdown schedule, and replacement with new design serviceable parts, 
and establishes a new cyclic life limit for existing compressor wheels.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other APUs of the same type design, this AD is 
being issued to prevent compressor wheel rupture. This AD requires 
removal from service of certain compressor wheels in accordance with a 
drawdown schedule, and replacement with serviceable parts, and 
establishes a new cyclic life limit for existing compressor wheels. The 
actions are required to be accomplished in accordance with the SB 
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

[[Page 68142]]

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.
    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-27.'' 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 USC 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

96-25-12  Sundstrand Aerospace: Amendment 39-9855. Docket 96-ANE-27.

    Applicability: Sundstrand Aerospace Models T-62T-40C series 
auxiliary power units (APUs), with compressor wheel, Part Numbers 
(P/Ns) 162690-1, 165111-1, and 167200-1. These APUs are installed on 
but not limited to Aerospatiale Super Puma, Boeing 707 series, 
British Aerospace HS 748 series, Cessna 650 series, Convair 650 and 
880 series, Dassault Aviation Falcon 20, 50 and 200 series, de 
Havilland DHC-7 and DHC-8 series, Embraer 120 series, Fokker F .27 
series, Gulfstream Aerospace Corporation 159, 1159, and G-III 
series, Hawker 700 series, Lockheed Jetstar 731 series, Raytheon 
Corporate Jets, Inc. BAe 125 series, Sabreliner Corporation NA-265 
series aircraft.

    Note 1: 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 (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 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 compressor wheel rupture, which could result in an 
uncontained APU failure and damage to the aircraft, accomplish the 
following:
    (a) Remove from service compressor wheels in accordance with the 
procedures described in the Accomplishment Instructions of 
Sundstrand Aerospace Service Bulletin (SB) No. SB-T-62T-49-120, 
Revision 2, dated November 5, 1996, Revision 1, dated September 9, 
1996, or Original, dated July 22, 1996, and the drawdown schedule 
described in Table 2 of Revision 2 only, dated November 5, 1996, and 
replace with serviceable parts.
    (b) This AD establishes a new life limit of 6,000 cycles for 
existing uninstalled compressor wheels, identified as Sundstrand P/
Ns 162690-1, 165111-1, and 167200-1.
    (c) 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 2: 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.

    (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) Thereafter, except as provided in paragraphs (c) and (d) of 
this AD, no alternative replacement time may be approved for 
compressor wheels, identified as Sundstrand P/Ns 162690-1, 165111-1, 
and 167200-1.
    (f) The actions required by this AD shall be done in accordance 
with the following Sundstrand Aerospace SBs:

------------------------------------------------------------------------
           Document No.               Revision   Pages        Date      
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SB-T-62-T-49-120..................            2    1-9  Nov. 5, 1996    
    Total pages: 9................                                      
SB-T-62-T-49-120..................            1    1-9  Sept. 9, 1996   
    Total pages: 9................                                      
SB-T-62-T-49-120..................     Original    1-9  July 22, 1996   
    Total pages: 9................                                      
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[[Page 68143]]

    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 Sundstrand Aerospace, 4400 
Ruffin Rd., P.O. Box 85757, San Diego, CA 92186-5757; telephone 
(619) 627-6303, fax (619) 627-6473. 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 January 13, 1997.

    Issued in Burlington, Massachusetts, on December 4, 1996.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 96-32181 Filed 12-26-96; 8:45 am]
BILLING CODE 4910-13-U