[Federal Register Volume 61, Number 73 (Monday, April 15, 1996)]
[Proposed Rules]
[Pages 16413-16414]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-9236]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-221-AD]


Airworthiness Directives; McDonnell Douglas Model DC-9-80 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-9-80 series airplanes and Model MD-88 airplanes. This proposal would 
require a one-time inspection to detect cracking of the main landing 
gear (MLG) pistons, and repair or replacement of the pistons with new 
or serviceable parts, if necessary. This proposal is prompted by 
reports of failure of the MLG pistons that occurred during towing of 
the airplanes. The actions specified by the proposed AD are intended to 
prevent fatigue cracking of the MLG pistons, which could result in 
failure of the pistons and subsequent damage to the airplane structure 
or injury to airplane occupants.

DATES: Comments must be received by June 10, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-221-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, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Technical Publications 
Business Administration, Department C1-L51 (2-60). 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: Brent Bandley, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone 
(310) 627-5237; 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-221-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-221-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received two reports of failure of the main landing 
gear (MLG) pistons that occurred during towing of a McDonnell Douglas 
Model DC-9-82 series airplane and a Model MD-88 airplane. In both 
cases, the fracture surface extended around the barrel section at the 
piston/axle transition. The fractures originated at a fatigue crack. 
Fatigue cracking occurred due to vibration-induced high stress loads on 
the pistons and a blending induced stress concentration in the 
transition area of the piston/axle transition. Such vibration occurs 
primarily during landing and rejected takeoff during moderate to heavy 
braking. Fatigue cracking of the MLG pistons, if not detected and 
corrected in a timely manner, could result in failure of the pistons 
and subsequent damage to the airplane structure or injury to airplane 
occupants.
    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletin MD80-32-277, Revision 01, dated February 23, 1996, which 
describes procedures for a one-time dye penetrant and magnetic particle 
inspection to detect cracking of the MLG pistons, and repair or 
replacement of cracked pistons with new or serviceable parts.
    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 dye penetrant and magnetic 
particle inspection to detect cracking of the MLG pistons, and repair 
or replacement of the pistons with new or serviceable parts, if 
necessary. The actions would be required to be accomplished in 
accordance with the service bulletin described previously.
    This is considered to be interim action until final action is 
identified, at which time the FAA may consider further rulemaking. -

[[Page 16414]]

    There are approximately 1,119 Model DC-9-80 series airplanes and 
Model MD-88 airplanes of the affected design in the worldwide fleet. 
The FAA estimates that 609 airplanes of U.S. registry would be affected 
by this proposed AD, that it would take approximately 2 work hours per 
airplane to accomplish the proposed actions, and that the average labor 
rate is $60 per work hour. Based on these figures, the cost impact of 
the proposed AD on U.S. operators is estimated to be $73,080, or $120 
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 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. 106(g), 40113, 44701.


Sec. 39.13  [Amended] -

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

McDonnell Douglas: Docket 95-NM-221-AD.

     -Applicability: Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 
(MD-83), and DC-9-87 (MD-87) series airplanes, and Model MD-88 
airplanes; as listed in McDonnell Douglas Service Bulletin MD80-32-
277, Revision 01, dated February 23, 1996; 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 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.

    -Compliance: Required as indicated, unless accomplished 
previously. -
    To prevent fatigue cracking of the main landing gear (MLG) 
pistons, which could result in failure of the pistons and subsequent 
damage to the airplane structure or injury to airplane occupants, 
accomplish the following: -
    (a) Perform a one-time dye penetrant and magnetic particle 
inspection to detect cracking of the MLG pistons, in accordance with 
McDonnell Douglas Service Bulletin MD80-32-277, Revision 01, dated 
February 23, 1996, at the later of the times specified in paragraphs 
(a)(1) and (a)(2) of this AD. -
    (1) Prior to the accumulation of 4,000 total landings on the MLG 
piston. -
    (2) Within 1,500 landings or 12 months after the effective date 
of this AD, whichever occurs first. -
    (b) If no cracking is found, no further action is required by 
this AD. -
    (c) If any cracking is found that is within the limits specified 
in McDonnell Douglas Service Bulletin MD80-32-277, Revision 01, 
dated February 23, 1996, prior to further flight, repair in 
accordance with the service bulletin. -
    (d) If any cracking is found that is outside the limits 
specified in McDonnell Douglas Service Bulletin MD80-32-277, 
Revision 01, dated February 23, 1996, prior to further flight, 
replace the MLG piston with a new or serviceable part in accordance 
with the service bulletin. -
    (e) As of the effective date of this AD, no person shall install 
an MLG piston having part number 5935347-1 through 5935347-509 
inclusive on any airplane unless that piston has been inspected in 
accordance with McDonnell Douglas Service Bulletin MD80-32-277, 
Revision 01, dated February 23, 1996, and found to be crack-free; or 
unless it is repaired or modified in accordance with the service 
bulletin. -
    (f) 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.

    (g) 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 April 9, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-9236 Filed 4-12-96; 8:45 am]
BILLING CODE 4910-13-U