[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]
BILLING CODE 4910-13-U