[Federal Register Volume 59, Number 235 (Thursday, December 8, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-30141]
[[Page Unknown]]
[Federal Register: December 8, 1994]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-181-AD]
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).
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 inspection to detect chafing on
the FIREX pipe assembly of the number one engine; and either
replacement of the chafed pipe assemblies with new pipe assemblies and
modification of the FIREX and the pneumatic sense pipe assembly clamp
marriage; or repair of the chafed pipe assemblies. This proposal is
prompted by reports of incidents in which the pneumatic sense pipe
chafed against the FIREX supply pipe of the number one engine. The
actions specified by the proposed AD are intended to prevent the
chafing of the FIREX supply pipe, which could result in a hole in the
pipe and subsequently prevent the proper distribution of the fire
extinguishing agent within the nacelle in the event of a fire.
DATES: Comments must be received by February 6, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-181-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 McDonnell Douglas Corporation, P.O. Box 1771, Long Beach,
California 90801-1771, Attention: Business Unit Manager, Technical
Administrative Support, Dept. L51, M.C. 2-98. 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, Transport Airplane Directorate, 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 94-NM-181-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. 94-NM-181-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received several reports of incidents in which a
pneumatic sense pipe chafed against the FIREX supply pipe of the number
one engine on McDonnell Douglas Model DC-9 series airplanes. These
pipes are located aft of the pressure bulkhead and inboard of longeron
15 left. In one incident, a 0.2 inch (5 mm) hole was worn into the
FIREX supply pipe. Investigation revealed that, due to vibration, the
pneumatic pipe and/or FIREX pipe assembly can move from its original
position during flight operations or landing. Chafing of the FIREX
supply pipe assembly could eventually create a hole in the pipe. Such a
hole, if not detected and corrected, could prevent the proper
distribution of the fire extinguishing agent within the nacelle in the
event of a fire.
The FAA has reviewed and approved McDonnell Douglas DC-9 Service
Bulletin 26-25, Revision 1, dated September 30, 1994, which describes
procedures for inspection to detect chafing of the FIREX pipe assembly
of the number one engine; and either replacement of the chafed pipe
assemblies with new pipe assemblies and modification of the FIREX and
the pneumatic sense pipe assembly clamp marriage, or repair of the
chafed pipe assemblies. Accomplishment of the modification will
reposition the clamp marriage to a more effective location and will
provide adequate separation between the FIREX and pneumatic pipe
assemblies.
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 inspection to detect chafing on FIREX pipe
assembly of the number one engine; and either replacement of the chafed
pipe assemblies with new pipe assemblies and modification of the FIREX
and the pneumatic sense pipe assembly clamp marriage, or repair of the
chafed pipe assemblies. The actions would be required to be
accomplished in accordance with the service bulletin described
previously.
[Note: As a result of recent communications with the Air
Transport Association (ATA) of America, the FAA has learned that, in
general, some operators may misunderstand the legal effect of AD's
on airplanes that are identified in the applicability provision of
the AD, but that have been altered or repaired in the area addressed
by the AD. Under these circumstances, at least one operator appears
to have incorrectly assumed that its airplane was not subject to an
AD. On the contrary, all airplanes identified in the applicability
provision of an AD are legally subject to the AD. If an airplane has
been altered or repaired in the affected area in such a way as to
affect compliance with the AD, the owner or operator is required to
obtain FAA approval for an alternative method of compliance with the
AD, in accordance with the paragraph of each AD that provides for
such approvals. A note has been included in this notice to clarify
this requirement.]
There are approximately 1,954 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 1,097 airplanes
of U.S. registry would be affected by this proposed AD, that it would
take approximately 1 work hour per airplane to accomplish the proposed
actions, and that the average labor rate is $60 per work hour. The cost
of required parts would be nominal. Based on these figures, the total
cost impact of the proposed AD on U.S. operators is estimated to be
$65,820, or $60 per airplane.
The total 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 accomplish
those actions in the future if this AD were not adopted.
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. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
McDonnell Douglas: Docket 94-NM-181-AD.
Applicability: Model DC-9-10, -20, -30, -40, and -50 series
airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83),
and DC-9-87 (MD-87) series airplanes; Model MD-88 airplanes; and
Model C-9 (Military) series airplanes; as listed in McDonnell
Douglas DC-9 Service Bulletin 26-25, Revision 1, dated September 30,
1994; certificated in any category.
Note 1: This AD applies to each airplane 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 airplanes that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must use the authority
provided in paragraph (b) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition; or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent the chafing of a hole in the FIREX supply pipe of the
number one engine, which could prevent the proper distribution of
the fire extinguishing agent within the nacelle in the event of a
fire, accomplish the following:
(a) Within 8 months after the effective date of this AD, perform
an inspection to detect chafing of the FIREX pipe assembly of the
number one engine, in accordance with McDonnell Douglas DC-9 Service
Bulletin 26-25, Revision 1, dated September 30, 1994.
(1) If any chafing is detected, prior to further flight, either
replace the chafed pipe assemblies with new pipe assemblies and
modify the FIREX and the pneumatic sense pipe assembly clamp
marriage; or repair chafed pipe assemblies; in accordance with the
service bulletin.
(2) If no chafing is detected, prior to further flight, modify
the FIREX and the pneumatic sense pipe assembly clamp marriage, in
accordance with the service bulletin.
(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
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.
Issued in Renton, Washington, on December 2, 1994.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-30141 Filed 12-7-94; 8:45 am]
BILLING CODE 4910-13-U
