[Federal Register Volume 65, Number 46 (Wednesday, March 8, 2000)]
[Rules and Regulations]
[Pages 12085-12088]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-5009]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-NE-34-AD; Amendment 39-11607; AD 2000-04-24]
RIN 2120-AA64
Airworthiness Directives; Honeywell International (formerly
AlliedSignal Inc.) 36-300(A), 36-280(B), and 36-280(D) Series 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 Honeywell International (formerly AlliedSignal Inc.) 36-
300(A), 36-280(B), and 36-280(D) series Auxiliary Power Units (APUs).
This amendment requires installation of an external load compressor
containment shield, or installation of a load compressor impeller with
lower stress concentrations. This amendment is prompted by reports of
load compressor impeller failures. The actions specified by this AD are
intended to prevent an
[[Page 12086]]
uncontained APU failure and damage to the airplane.
DATES: Effective May 8, 2000.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of May 8, 2000.
ADDRESSES: The service information referenced in this AD may be
obtained from Honeywell International, Inc., Attn: Data Distribution,
M/S 64-3/2101-201, PO Box 29003, Phoenix, AZ 85038-9003; telephone 602-
365-2493, fax 602-365-5577. This information may be examined at the
Federal Aviation Administration (FAA), New England Region, Office of
the Regional 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: 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: 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 Honeywell International (formerly
AlliedSignal Inc.) 36-300(A), 36-280(B), and 36-280(D) series Auxiliary
Power Units (APUs) was published in the Federal Register on September
8, 1999 (64 FR 48723). That action proposed to require installation of
an external load compressor containment shield at the next shop visit,
or 6 months after the effective date of this AD, whichever occurs
first. An additional compliance option would be installation of a load
compressor impeller, part number (P/N) 3822270-5, to extend cyclic
service life to 26,000 cycles-since-new (CSN) before mandatory
installation of the containment shield. Operators cannot operate with a
load compressor installed, P/N 3822270-5, past 26,000 CSN unless they
have installed an external containment shield. That action was prompted
by three incidents where the load compressor impellers separated,
resulting in uncontained APU failures and debris entering the APU
compartment. That condition, if not corrected, could result in an
uncontained APU failure and damage to the airplane.
Comments Received
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Expand the Applicability
One commenter requests to add load compressor impeller, P/Ns
3822270-1 and 3822270-3, to the applicability in addition to P/Ns
3822270-4 and 3822270-5. Both load compressor impellers, P/Ns 3822270-1
and 3822270-3, are affected by the same damper ring groove condition as
the impellers already affected by the proposal. The FAA does not
concur. While impellers, P/Ns 3822270-1 and 3822270-3, are subject to
the same failure mode as P/N 3822270-4 load compressor impellers
affected by this AD, all load compressor impellers, P/Ns 3822270-1 and
3822270-3, were required to be reworked to the P/N 3822270-4
configuration by AD 92-21-05. The FAA has added a note referring to the
requirement of AD 92-21-05 to remind operators that the old load
compressor impeller designs shall no longer be used in service.
Clarification of Cyclic Determination
One commenter requests clarification in how to determine the number
of cycles on load compressor impellers in service. The commenter wishes
to use its existing system for determining the number of cycles on the
load compressor impellers instead of the method described by the
manufacturer in its applicable service bulletin (SB). The FAA concurs.
Since the AD does not require the use of the SB's cycle counting
methodology, operators may use their own approved system to calculate
cycles. A note has been added following paragraph (b) to address
acceptable methods of determining part cycles.
Subsequent Serial Number (S/N) Parts
The same commenter notes that the AlliedSignal Inc. SB does not
list all P/N 3822270-5 impellers in service. The FAA concurs. When the
SB was written all subsequent S/N parts that would be produced could
not have been anticipated. Since all S/Ns are affected, the
applicability paragraph in this final rule has been rewritten to
clarify that this AD applies to APUs with P/N 3822270-4 or -5 impellers
installed. The applicability paragraph of the AD takes precedence over
the AlliedSignal Inc. SB's list of S/Ns. For parts not listed
specifically in the SB, the SB provides a procedure to obtain the
required information.
Clarification of Compliance Times
The same commenter requests clarification on the compliance times
for load compressor impellers, P/N 3822270-5. The commenter notes there
appears to be contradictory requirements between paragraphs (b) and (c)
of the proposal. Paragraph (b) of the proposal allows operating
impellers, P/N 3822270-5, above 26,000 CSN, for six months after the
effective date of the AD. Paragraph (c) requires that an external
containment shield be in place before operating the APU past 26,000
CSN. The FAA concurs. Paragraph (c) of this final rule has been
modified to clarify that the calendar time requirement applies along
with the cycle time limit.
Can an Operator Remove the Containment Shield With a Lower Time
Impeller Installed?
The same commenter requests clarification on the possibility of
removal of the external load compressor containment shield when a lower
time impeller is installed. The same commenter also asks why APUs
containing P/N 3822270-5 load compressor impellers are not managed to a
26,000 CSN life limit. The commenter states that the proposal does not
specifically prohibit removing the external containment shield when P/N
3822270-5 load compressor impellers with less than 26,000 CSN are
installed. Operating to a 26,000 CSN limit would be preferred to
incorporation of an external load compressor containment shield because
it would avoid the potential for APU damage in the event that an
impeller does fail. The FAA concurs in part. The commenter may choose,
within the requirements of this final rule, to operate with low time P/
N 3822270-5 impellers installed without external load compressor
containment shields, or with P/N 3822270-5 impellers with more than
26,000 CSN and external load compressor containment shields installed.
Extend Calendar End-Date
One commenter requests an extension from six months to two years
for the calendar end-date for APUs containing P/N 3822270-5 load
compressor impellers. The commenter believes that there is inadequate
information available to accurately determine the actual number of
cycles on load compressor impellers. The commenter therefore believes
that the only practical means of complying with the AD is the calendar
method. Extension from six months to two years would allow for orderly
scheduling of the installation of the containment shield with scheduled
maintenance intervals. The FAA concurs in part. Although detailed load
[[Page 12087]]
compressor impeller cycle times are not known for all APUs, the
AlliedSignal SB procedure provides a method for assigning cyclic times
which are reasonable based upon review of APU operating history. The
FAA has determined that for impellers, P/N 3822270-5, an extension of
the calendar end-date from six months to one year would be reasonable
to allow incorporation of the containment shield with scheduled
maintenance intervals while maintaining an adequate safety level.
APU Model Numbers
The APUs affected by this AD are sometimes referred to as GTCP36-
300(A), GTCP36-280(B) and GTCP36-280(D) series APUs. The presence or
absence of the letters ``GTCP'' preceding the model number does not
affect the applicability of this AD on those APUs. The FAA has added a
note to clarify that the AD applies to the specified APU series whether
or not the letters ``GTCP'' appear on the dataplate.
New Company Name
Since publication of the proposal, AlliedSignal has adopted the
Honeywell International, Inc. name. This final rule has been altered
accordingly to refer to the new company name with AlliedSignal Inc.
listed as the former company name.
Concur With Proposal
One commenter concurs with the rule as proposed.
Conclusion
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 with the changes described
previously. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Economic Analysis
There are approximately 1,044 APUs of the affected design in the
worldwide fleet. The FAA estimates that 465 APUs installed on airplanes
of US registry will be affected by this AD, that it will take
approximately 6 work hours per Model 36-300(A) APU (85 units) to
accomplish the proposed actions, and 8 work hours per Model 36-280(D)
APU (380 units), and that the average labor rate is $60 per work hour.
Required parts will cost approximately $3,103 per APU. Fifteen
installations on domestic Boeing 737 aircraft (Model 36-280(B)) will
require a tube assembly kit, which would cost approximately $1,042. The
manufacturer has informed the FAA that it may offset some of these
costs thereby lowering the total cost to operators. Based on these
figures, the total cost impact of the AD on US operators is estimated
to be $1,725,270.
Regulatory Impact
The regulations adopted herein 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. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
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:
2000-04-24 Honeywell International (formerly Allied Signal Inc.):
Amendment 39-11607. Docket 99-NE-34-AD.
Applicability: Honeywell International (formerly AlliedSignal
Inc.) 36-300(A), 36-280(B), and 36-280(D) series Auxiliary Power
Units (APUs), with load compressor impellers, part numbers (P/Ns)
3822270-4, or 3822270-5, installed. These APUs are installed on but
not limited to Airbus Industrie A319, A320, and A321 series; Boeing
737-300, -400, -500 series; and McDonnell Douglas MD-80 series
airplanes.
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 (f) 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.
Note 2: The presence or absence of the letters ``GTCP''
preceding the model series does not affect the applicability of this
AD to the specified model APUs.
Note 3: AD 92-21-05 requires that all APUs with load compressor
impellers, P/Ns 3822270-1 or 3822270-3, be reworked to
the -4 configuration.
Compliance: Required as indicated, unless accomplished
previously.
To prevent an uncontained APU failure and damage to the
airplane, accomplish the following:
Load Compressor Impellers, P/N 3822270-4
(a) For APUs with load compressor impellers, P/N 3822270-4, at
the next shop visit, or within 6 months after the effective date of
this AD, whichever occurs first, accomplish either of the following:
(1) Install an external load compressor containment shield in
accordance with AlliedSignal Inc. Service Bulletins (SBs) No.
GTCP36-49-7471, dated April 20, 1999, GTCP36-49-7472, dated March
31, 1999, or GTCP36-49-7473, dated March 31, 1999, as applicable; or
(2) Install load compressor impeller, P/N 3822270-5.
Load Compressor Impellers, P/N 3822270-5
(b) For APUs with load compressor impellers, P/N 3822270-5,
install an external load compressor containment shield within one
year after the effective date of this AD, or prior to the impeller
exceeding 26,000 cycles-since-new (CSN), whichever occurs later, in
accordance with AlliedSignal Inc. SBs No. GTCP36-49-7471, dated
April 20, 1999, GTCP36-49-7472, dated March 31, 1999, or GTCP36-49-
7473, dated March 31, 1999, as applicable.
Note 4: Operators may use their own FAA-approved tracking system
for determining load compressor impeller cyclic count in lieu of the
procedure described in the AlliedSignal Inc. SBs referenced in this
AD.
[[Page 12088]]
Cyclic Limit without External Containment Shield
(c) Following one year after the effective date of this AD,
operators cannot operate with a load compressor, P/N 3822270-5,
installed, past 26,000 cycles unless they have installed an external
load compressor containment shield.
Definition
(d) For the purpose of this AD, a shop visit is defined as when
the APU is inducted into a shop for any reason.
Alternative Methods of Compliance
(e) 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. Operators shall submit their request through an appropriate
FAA Principal Maintenance Inspector, who may add comments and then
send it to the Manager, Los Angeles Aircraft Certification Office.
Note 5: 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.
Ferry Flights
(f) 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 airplane to a location where
the requirements of this AD can be accomplished.
Incorporation by Reference
(g) The actions required by this AD shall be done in accordance
with the following AlliedSignal Inc. SBs: GTCP36-49-7471, dated
April 20, 1999, GTCP36-49-7472, dated March 31, 1999, and GTCP36-49-
7473, dated March 31, 1999. 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
Honeywell International, Inc., Attn: Data Distribution, M/S 64-3/
2101-201, PO 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 Regional 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.
(h) This amendment becomes effective on May 8, 2000.
Issued in Burlington, Massachusetts, on February 25, 2000.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 00-5009 Filed 3-7-00; 8:45 am]
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