[Federal Register Volume 61, Number 206 (Wednesday, October 23, 1996)]
[Proposed Rules]
[Pages 54961-54963]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-27122]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-199-AD]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-9, DC-9-80,
and C-9 (Military) Series Airplanes, and Model MD-88 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain McDonnell Douglas Model
DC-9, DC-9-80, and C-9 (military) series airplanes, and Model MD-88
airplanes. This proposal would require modification of certain non-
regulating shutoff valves on the engine starter. This proposal is
prompted by reports of uncontained failures of engine starters during
flight and maintenance, which resulted from the application of
excessive pressure on the engine starter that was associated with the
installation of non-regulating shutoff valves on the starter. The
actions specified by the proposed AD are intended to prevent such
uncontained failures of the engine starters, which could create a fire
hazard in the engine nacelle.
DATES: Comments must be received by December 2, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-
[[Page 54962]]
199-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments
may be inspected at this location between 9:00 a.m. and 3:00 p.m.,
Monday through Friday, except Federal holidays.
The service information referenced in the proposed rule may be
obtained from AlliedSignal Aerospace, Technical Publications, Dept. 65-
70, P.O. Box 52170, Phoenix, Arizona 85072-2170. This information may
be examined at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Robert Baitoo, Aerospace Engineer,
Propulsion Branch, ANM-140L, FAA, Los Angeles Aircraft Certification
Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone
(310) 627-5245; fax (310) 627-5210.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed rule by submitting such written data, views, or arguments as
they may desire. Communications shall identify the Rules Docket number
and be submitted in triplicate to the address specified above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule. The proposals contained in this notice may be changed in
light of the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with
the substance of this proposal 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-NM-199-AD.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 96-NM-199-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received reports indicating that uncontained failures
of engine starters on some McDonnell Douglas Model DC-9-80 series
airplanes have occurred during flight and during maintenance. In the
former circumstance, the failure of the engine starter occurred when
the pneumatic augmentation valve failed in the open position. In the
latter circumstance, the engine was being used as a source of
compressed air for testing the pneumatic ducts, and the pneumatic
augmentation valve was placed in the open position.
In each of these uncontained failures, the valve on the engine
starter was a converted non-regulating shutoff valve. This non-
regulating shutoff valve initially had been produced as a regulating
and shutoff valve; it was later converted to its non-regulating
configuration in accordance with procedures described in a service
bulletin issued by the valve manufacturer, AlliedSignal Aerospace
(formerly Garrett).
An evaluation revealed that elimination of the regulating feature
from the engine starter valve can result in the application of
excessive pressure on the starter. This condition, if not corrected,
could cause an uncontained failure of the starter and, consequently,
could create a fire hazard in the engine nacelle.
Since these non-regulating shutoff valves can be installed on any
McDonnell Douglas Model DC-9, DC-9-80, and C-9 (military) series
airplanes, and Model MD-88 airplanes, all of these models may be
subject to this same unsafe condition.
Explanation of Relevant Service Information
The FAA has reviewed and approved AlliedSignal Aerospace Service
Bulletin 979410-80-1611, dated November 27, 1995, which describes
procedures for modification of certain converted or first production
non-regulating shutoff valves on the engine starter by installation of
a pressure regulator on the valve. Accomplishment of this modification
entails reworking the valve into a regulating and shutoff valve.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would require modification of certain converted or first
production non-regulating shutoff valves on the engine starter. The
actions would be required to be accomplished in accordance with the
service bulletin described previously.
Differences Between Proposed Rule and Relevant Service Information
The proposed AD and the referenced service bulletin differ as to
the compliance times specified in each: The proposed AD would require
that the modification be accomplished within 12 months after the
effective date of the AD; however, the service bulletin recommends that
the modification be accomplished within 8 months.
In developing an appropriate compliance time for this action, the
FAA considered not only the safety implications, but the average
utilization rate of the affected fleet, the availability of required
modification parts, and normal maintenance schedules of affected
operators for timely accomplishment of the modification. After
evaluating these factors, the FAA has determined that a 12-month
compliance period is appropriate in that:
1. It will allow the modification to be performed during a
regularly scheduled maintenance interval at a main base, where
necessary tooling and trained personnel will be available. This will
minimize any costs that would be associated with the necessary
disruption of fight schedules in order to special schedule airplanes
for accomplishment of the modification.
2. It also will provide adequate time for the valve manufacturer to
ensure that ample modification kits are available for the U.S. fleet;
for operators to order and receive the kits; and for the fleet to be
modified in an orderly and timely manner.
Cost Impact
There are approximately 1,970 Model DC-9, DC-9-80, and C-9
(military) series airplanes and Model MD-88 airplanes of the affected
design in the worldwide fleet. The FAA estimates that 1,100 airplanes
of U.S. registry would be affected by this proposed AD, that it would
take approximately 16 work hours per airplane to accomplish the
proposed actions, and that the average labor rate is $60 per work hour.
Required parts would cost approximately $400 per airplane. Based on
these figures, the cost impact of the proposed AD on U.S. operators is
estimated to be $1,496,000, or $1,360 per airplane.
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished any of the proposed requirements of
this AD action, and that no operator would
[[Page 54963]]
accomplish those actions in the future if this AD were not adopted.
Regulatory Impact
The regulations proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this proposed
regulation (1) Is not a ``significant regulatory action'' under
Executive Order 12866; (2) is not a ``significant rule'' under the DOT
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
and (3) if promulgated, 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 copy of the draft
regulatory evaluation prepared for this action is contained in the
Rules Docket. A copy of it may be obtained by contacting the Rules
Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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:
McDonnell Douglas: Docket 96-NM-199-AD.
Applicability: Model DC-9, DC-9-80, and C-9 (military) series
airplanes and Model MD-88 airplanes, on which a converted or first
production non-regulating shutoff valve having AlliedSignal
Aerospace part number (P/N) 979410-1-1 or 979410-2-1 has been
installed on the engine starter; certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes 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 (b) 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 the application of excessive pressure on the engine
starter, which could cause uncontained failure of an engine starter
and, consequently, could create a fire hazard in the nacelle of the
engine, accomplish the following:
(a) Within 12 months after the effective date of this AD, modify
any converted or first production non-regulating shutoff valve, P/N
979410-1-1 or 979410-2-1, on the engine starter by installing a
pressure regulator on the valve in accordance with AlliedSignal
Aerospace Service Bulletin 979410-80-1611, dated November 27, 1995.
(b) 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 (ACO), FAA, Transport Airplane Directorate. 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 ACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
(c) Special flight permits may be issued in accordance with
section 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.
Issued in Renton, Washington, on October 16, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-27122 Filed 10-22-96; 8:45 am]
BILLING CODE 4910-13-U
