[Federal Register Volume 60, Number 73 (Monday, April 17, 1995)]
[Proposed Rules]
[Pages 19188-19190]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-9351]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-36-AD]
Airworthiness Directives; McDonnell Douglas Model DC-9 Series
Airplanes and C-9 (Military) 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 Model DC-9 series
airplanes and C-9 (military) airplanes. This proposal would require an
inspection of the driver links of the thrust reverser door to determine
whether the driver links are chamfered, an inspection to detect damage
of the overcenter links, and follow-on corrective actions, if
necessary; and replacement or rework of the driver links. This proposal
is prompted by reports of a thrust reverser door that failed to operate
properly due to improperly manufactured (missing chamfers on the)
driver links. The actions specified by the proposed AD are intended to
prevent damage to the overcenter links due to missing chamfers on the
driver links, which may result in uncommanded opening of the thrust
reverser door, and subsequently, adversely affecting controllability of
the airplane.
DATES: Comments must be received by June 9, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-36-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; or at the FAA, Transport Airplane Directorate,
Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California.
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 95-NM-36-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. 95-NM-36-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
Recently, an operator of McDonnell Douglas Model DC-9 series
airplanes reported that the thrust reverser door would not close after
an airplane landed. Subsequently, this same operator reported that the
thrust reverser door, on the same airplane, opened partially after
takeoff. Investigation revealed that driver links of the thrust
reverser on this airplane were bent or broken, apparently due to a
manufacturing defect. These driver links were missing chamfers, which
caused damage to the adjoining overcenter links, and eventually led to
the failure of the overcenter link assembly. This condition, if not
corrected, could result in uncommanded opening of the thrust reverser
door, which may adversely affect controllability of the airplane.
The FAA has reviewed and approved McDonnell Douglas DC-9 Alert
Service Bulletin A78-67, dated February 27, 1995, which describes
procedures for a one-time visual inspection of the driver links of the
thrust reverser door to determine whether the driver links are
chamfered. For driver links that are not chamfered, this alert service
bulletin describes procedures for removal of the driver link and an
inspection to determine serviceability of the driver link. This alert
service bulletin also describes procedures for a one-time visual
inspection to detect damage of the overcenter links, and an inspection
to detect damage of the drive mechanism, if necessary. Additionally,
this alert service bulletin describes procedures for replacement or
rework of the driver links.
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 a one-time visual inspection of the driver
links of the thrust reverser door to determine whether the driver links
are chamfered, and a one-time [[Page 19189]] visual inspection to
detect damage of the overcenter links, and follow-on corrective
actions, if necessary; and replacement or rework of the driver links.
The actions would be required to be accomplished in accordance with the
alert service bulletin described previously.
The proposed AD would also require that operators submit a report
of the findings of the inspection required by this proposal. The
information obtained from these reports will enable the FAA to
determine how widespread the problem is in the fleet and if additional
action is warranted.
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. The FAA
points out that 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 long-standing requirement.
There are approximately 892 airplanes of the affected design in the
worldwide fleet. The FAA estimates that 557 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 inspections and
approximately 10 work hours per airplane to accomplish the proposed
replacement/rework, and that the average labor rate is $60 per work
hour. Required replacement/rework parts would cost approximately $4,100
per airplane. Based on these figures, the total cost impact of the
proposed AD on U.S. operators is estimated to be $2,651,320, or $4,760
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 95-NM-36-AD.
Applicability: Model DC-9-10, -20, -30, -40, and -50 series
airplanes, and C-9 (military) airplanes, as listed in McDonnell
Douglas DC-9 Alert Service Bulletin A78-67, dated February 27, 1995,
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 (e) 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 uncommanded opening of the thrust reverser door,
which may adversely affect controllability of the airplane,
accomplish the following:
(a) Within 3 months after the effective date of this AD, perform
a visual inspection of the actuating mechanisms of the upper and
lower doors of the thrust reverser on the left and right engines to
determine whether the driver links are chamfered, in accordance with
McDonnell Douglas DC-9 Alert Service Bulletin A78-67, dated February
27, 1995.
(1) If all the driver links are chamfered, prior to further
flight, perform a visual inspection to detect damage of the
overcenter links (including the bearings, races, and attaching
hardware), in accordance with the alert service bulletin.
(i) If no damage to the overcenter links is detected, no further
action is required by this paragraph.
(ii) If any damage to the overcenter links is detected, prior to
further flight, replace the damaged overcenter links with new or
serviceable overcenter links.
(iii) If any damage to the bearings, races, or attaching
hardware of the overcenter links is detected, prior to further
flight, perform a visual inspection to detect damage of the drive
mechanism of the thrust reverser, in accordance with the alert
service bulletin. If any damage to the drive mechanism is detected,
prior to further flight, repair or replace the damaged parts with
new or serviceable parts, in accordance with the Chapter 78 of the
DC-9 Overhaul Manual.
(2) If any driver link is not chamfered, prior to further
flight, remove the driver link and perform dimensional and
flourescent penetrant inspections to determine serviceability of the
driver link, in accordance with the alert service bulletin.
(i) If the driver link is serviceable, prior to further flight,
machine chamfer the driver link, or replace the driver link with a
new or serviceable part, in accordance with the alert service
bulletin.
(ii) If the driver link is not serviceable, prior to further
flight, replace it with a new or serviceable driver link, in
accordance with the alert service bulletin.
(b) Within 3 months after the effective date of this AD, perform
a visual inspection to detect damage of the overcenter links
(including the bearings, races, and attaching hardware, in
accordance with the McDonnell Douglas DC-9 Alert Service Bulletin
A78-67, dted February 27, 1995.
(1) If no damage to the overcenter links is detected, no further
action is required by this paragraph.
(2) If any damage to the overcenter links is detected, prior to
further flight, replace the damaged overcenter links with new or
serviceable overcenter links.
(3) If any damage to the bearings, races, or attaching hardware
of the overcenter links is detected, prior to further flight,
perform a [[Page 19190]] visual inspection to detect damage of the
drive mechanism of the thrust reverser, in accordance with the alert
service bulletin. If any damage to the drive mechanism is detected,
prior to further flight, repair or replace the damaged parts with
new or serviceable parts, in accordance with the Chapter 78 of the
DC-9 Overhaul Manual.
(c) Within 10 days after accomplishing the visual inspection of
the driver links of the thrust reverser door to determine whether
the driver links are chamfered, as required by paragraph (a) of this
AD, submit a report of the inspection results (both positive and
negative findings) to the Manager, FAA, Transport Airplane
Directorate, Los Angeles Aircraft Certification Office (ACO), 3960
Paramount Boulevard, Lakewood, California 90712; telephone (310)
627-5245; fax (310) 627-5210; Attention: Robert Baitoo. Information
collection requirements contained in this regulation have been
approved by the Office of Management and Budget (OMB) under the
provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et
seq.) and have been assigned OMB Control Number 2120-0056.
(d) As of the effective date of this AD, no person shall
install, on any airplane, a driver link or overcenter link assembly
of a thrust reverser that has not been previously inspected, and
replaced or reworked, in accordance with McDonnell Douglas DC-9
Alert Service Bulletin A78-67, dated February 27, 1995.
(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 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.
(f) Special flight permits may be issued in accordance with
Secs. 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 April 10, 1995.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-9351 Filed 4-14-95; 8:45 am]
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