AD Amdt-39-13879

final rule

Airworthiness Directives; Hamilton Sundstrand Power Systems T-62T Series Auxiliary Power Units (APUs)

AD Number
Amdt-39-13879
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2003-NE-61-AD
FR Citation
69 FR 68767
Technical illustration of an aircraft fuel pump, filter, valve, and lines
Problem area Fuel system

Unsafe Condition

Reports of leaks caused by cracked bypass buttons that protruded beyond the internal o-ring seal, leading to a potential fire or explosion from a fuel leak.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Install a bracket onto the fuel filter housing assembly to prevent a failed bypass button from protruding beyond the internal o-ring seal. Use specific Alert Service Bulletins (ASBs) for installation instructions. Perform a one-time inspection for proper gap adjustment if brackets were previously installed using certain ASBs.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 500 hours time-in-service or 6 months after the effective date of this AD, whichever occurs earlier.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Hamilton Sundstrand Power Systems Models T-62T-46C12 and T-62T-40C14 (APS 500R) APUs with fuel filter housing assemblies, part numbers 4951627, 4951960, or 4952039, installed. These APUs are installed on, but not limited to, Bombardier DHC-8-400 airplanes and Embraer EMB-135 and -145 series airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

The FAA is adopting a new airworthiness directive (AD) for Hamilton Sundstrand Power Systems Models T-62T-46C12 and T-62T-40C14 (APS 500R) APUs with fuel filter housing assembly, part number (P/N) 4951627, 4951960, or 4952039, installed. This AD requires installation of a bracket to prevent a failed bypass button from protruding beyond the internal o-ring seal. This AD results from reports of leaks caused by cracked bypass buttons that protruded beyond the o-ring seal. We are issuing this AD to prevent a fire or explosion caused by a fuel leak from a failed bypass button on the fuel filter housing.

Document Text

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[Federal Register Volume 69, Number 227 (Friday, November 26, 2004)]
[Rules and Regulations]
[Pages 68767-68769]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 04-25792]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-61-AD; Amendment 39-13879 AD 2004-24-03]
RIN 2120-AA64


Airworthiness Directives; Hamilton Sundstrand Power Systems T-62T 
Series Auxiliary Power Units (APUs)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
Hamilton Sundstrand Power Systems Models T-62T-46C12 and T-62T-40C14 
(APS 500R) APUs with fuel filter housing assembly, part number (P/N) 
4951627, 4951960, or 4952039, installed. This AD requires installation 
of a bracket to prevent a failed bypass button from protruding beyond 
the internal o-ring seal. This AD results from reports of leaks caused 
by cracked bypass buttons that protruded beyond the o-ring seal. We are 
issuing this AD to prevent a fire or explosion caused by a fuel leak 
from a failed bypass button on the fuel filter housing.

DATES: This AD becomes effective January 3, 2005. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of January 3, 2005.

ADDRESSES: You can get the service information identified in this AD 
from Hamilton Sundstrand Technical Publications Department, P.O. Box 
7002, Rockford, IL 61125-7002, U.S.A.
    You may examine the AD docket at the FAA, New England Region, 
Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA. You may examine the service information, at the FAA, 
New England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.

FOR FURTHER INFORMATION CONTACT: Roger Pesuit, Aerospace Engineer, Los 
Angeles Aircraft Certification Office, FAA, Transport Airplane 
Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone 
(562) 627-5251, fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed airworthiness directive (AD). The proposed AD applies 
to Hamilton Sundstrand Power Systems Models T-62T-46C12 and T-62T-40C14 
(APS 500R) APUs with fuel filter housing assembly, P/N 4951627, 
4951960, or 4952039 installed. We published the proposed AD in the 
Federal Register on May 7, 2004 (69 FR 25525). That action proposed to 
require installation of a bracket to prevent a failed bypass button 
from protruding beyond the internal o-ring seal.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Request To Add Alert Service Bulletin Reference

    Two commenters request that for APUs Model T-62T-40C14 (APS 500R),

[[Page 68768]]

we add EMBRAER Alert Service Bulletin (ASB) No. 145-49-A027, dated 
January 6, 2004, as another means of complying with the AD. We do not 
agree. That ASB does not contain instructions for installing the 
bracket, but only instructs the operator to use Hamilton Sundstrand ASB 
No. ASB-4504112-49-22, for installing the bracket. Because of this, we 
have not incorporated by reference that ASB.

Request To Reference the Latest ASB Revision

    One commenter requests that we reference the latest revision of 
Hamilton Sundstrand ASB No. ASB-4504112-49-22, which is Revision 1, 
dated January 5, 2004. The commenter states that the original ASB 
specified a gap dimension of 0.32 inch-to-0.65 inch, which is incorrect 
and unachievable. ASB Revision 1 corrects the gap dimension to the 
proper value of 0.50 inch, plus or minus 0.015 inch. Also, ASB Revision 
1 increases the recommended compliance threshold from within 400 hours 
time-in-service (TIS) to within 500 hours TIS.
    We agree that the latest ASB Revision should be referenced, which 
is Revision 2, dated October 4, 2004. The 500 hours TIS threshold is 
consistent with EMBRAER ASB No. 145-49-A027, dated January 6, 2004. ASB 
Revision 2 requires, as does this AD, that brackets installed using 
Hamilton Sundstrand ASB No. ASB-4504112-49-22, Original issue, be 
inspected one time for proper gap and adjusted if necessary. ASB 
Revision 2 also introduces as an alternative, the installation of a 
different part number fuel filter assembly for APU Model T-62-T-40C14, 
that is designed to prevent bypass button failure. We have added that 
alternative as optional terminating action for APU Model T-62-T-40C14.
    We are allowing previous credit for brackets installed using 
Hamilton Sundstrand ASB No. ASB-4504112-49-22, Original, dated December 
2, 2003, or Revision 1, dated January 5, 2004, before the effective 
date of this AD. We have incorporated the changes described previously 
in this AD.

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are about 552 Hamilton Sundstrand APUs of the affected design 
in the worldwide fleet. We estimate that 448 APUs installed on 
airplanes of U.S. registry will be affected by this AD. We also 
estimate that it would take about 1 work hour per APU to perform the 
actions, and that the average labor rate is $65 per work hour. Required 
parts will cost about $517 per APU. The manufacturer indicated that 
they might provide the parts at no cost. Based on these figures, we 
estimate the total cost of the AD to U.S. operators to be $260,736.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will not have a 
substantial direct effect 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.
    For the reasons discussed above, I certify that this AD:
    (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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-NE-61-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2004-24-03 Hamilton Sundstrand Power Systems: Amendment 39-13879. 
Docket No. 2003-NE-61-AD.

Effective Date

    (a) This AD becomes effective January 3, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Hamilton Sundstrand Power Systems Models 
T-62T-46C12 and T-62T-40C14 (APS 500R) auxiliary power units (APUs) 
with fuel filter housing assemblies, part numbers (P/Ns) 4951627, 
4951960, or 4952039, installed. These APUs are installed on, but not 
limited to, Bombardier DHC-8-400 airplanes and Empresa Brasileira de 
Aeronautica S.A. (EMBRAER) EMB-135 and -145 series airplanes.

Unsafe Condition

    (d) This AD results from reports of leaks caused by cracked 
bypass buttons that protruded beyond the o-ring seal. We are issuing 
this AD to prevent a fire or explosion caused by a fuel leak from a 
failed bypass button on the fuel filter.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within 500 hours time-in-service or 6 months after the 
effective date of this AD, whichever occurs earlier, unless the 
actions have already been done.

Installation of Bracket on APU Model T-62T-46C12

    (f) Install a bracket onto the fuel filter housing assembly on 
APU Model T-62T-46C12. Use 2.A through 2.D of the Accomplishment 
Instructions of Hamilton Sundstrand Alert Service Bulletin (ASB) No. 
ASB-4503067-49-9, dated December 2, 2003, to install the bracket.

Installation of Bracket on APU Model T-62T-40C14 (APS 500R)

    (g) Install a bracket onto the fuel filter housing assembly on 
APU Model T-62T-40C14 (APS 500R). Use 2.B. and 2.D.(1) of the 
Accomplishment Instructions of Hamilton Sundstrand ASB No. ASB-
4504112-49-22, Revision 2, dated October 4, 2004, to install the 
bracket.

Previous Credit

    (h) Previous credit is allowed for brackets installed using 
Hamilton Sundstrand ASB No. ASB-4503067-49-9, dated December 2, 
2003, Hamilton Sundstrand ASB No. ASB-4504112-49-22, Original, dated 
December 2, 2003, or Revision 1, dated January 5, 2004, before the 
effective date of this AD.

One-Time Inspection for Proper Gap

    (i) For brackets previously installed using Hamilton Sundstrand 
ASB No. ASB-4504112-49-22, Original, dated December 2, 2003, perform 
a one-time inspection for proper gap and if necessary, adjust the 
gap between the bracket and bypass button. Use 2.B. and 2.D.(1) of 
the Accomplishment

[[Page 68769]]

Instructions of Hamilton Sundstrand ASB No. ASB-4504112-49-22, 
Revision 2, dated October 4, 2004 to inspect and adjust the gap.

Optional Terminating Action for APU Model T-62T-40C14 (APS 500R)

    (j) For APU Model T-62T-40C14 (APS 500R), installation of a part 
number fuel filter assembly that is not listed in this AD 
constitutes optional terminating action to the requirements of this 
AD.

Alternative Methods of Compliance

    (k) The Manager, Los Angeles Aircraft Certification Office, has 
the authority to approve alternative methods of compliance for this 
AD if requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

    (l) You must use the Alert Service Bulletins listed in Table 1 
of this AD to perform the bracket installations required by this AD. 
The Director of the Federal Register approved the incorporation by 
reference of the documents listed in Table 1 of this AD in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You can get a 
copy from Hamilton Sundstrand Technical Publications Department, 
P.O. Box 7002, Rockford, IL 61125-7002, U.S.A. You can review copies 
at the FAA, New England Region, Office of the Regional Counsel, 12 
New England Executive Park, Burlington, MA; or at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to: 
<a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>. Table 1 follows:

                                      Table 1.--Incorporation by Reference
----------------------------------------------------------------------------------------------------------------
                                    Page number(s) shown   Revision level shown
    Alert service bulletin No.           on the page           on the page            Date shown on the page
----------------------------------------------------------------------------------------------------------------
Hamilton Sundstrand ASB-4503067-49- All.................  Original.............  December 2, 2003.
 9.
Hamilton Sundstrand ASB-4504112-49- All.................  2....................  October 4, 2004.
 22.
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Related Information

    (m) None.

    Issued in Burlington, Massachusetts, on November 15, 2004.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 04-25792 Filed 11-24-04; 8:45 am]
BILLING CODE 4910-13-P

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