AD 2001-09-18

[Federal Register Volume 66, Number 91 (Thursday, May 10, 2001)]
[Rules and Regulations]
[Pages 23840-23845]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-11674]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-164-AD; Amendment 39-12225; AD 2001-09-18]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-9-80 Series 
Airplanes and Model MD-88 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to certain McDonnell Douglas Model DC-9-80 series 
airplanes and Model MD-88 airplanes, that currently requires 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 amendment requires, among other actions, repetitive 
dye penetrant and magnetic particle inspections to detect cracks of the 
MLG pistons; repair and replacement of discrepant parts; and 
installation of a preventative modification; as applicable. This 
amendment also provides for an optional terminating action for certain 
MLG pistons. This amendment is prompted by additional reports of 
failure of the MLG pistons during towing of the airplanes. The actions 
specified by this AD are intended to prevent fatigue cracking of the 
MLG pistons, which could result in

[[Page 23841]]

failure of the pistons and subsequent damage to the airplane structure 
or injury to airplane occupants.

DATES: Effective June 14, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 14, 2001.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Aircraft Group, Long Beach Division, 
3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data 
and Service Management, Dept. C1-L5A (D800-0024). This information may 
be examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, Los Angeles Aircraft Certification Office, 
3960 Paramount Boulevard, Lakewood, California; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, Washington, 
DC.

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: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 96-19-09, 
amendment 39-9756 (61 FR 48617, September 16, 1996), which is 
applicable to certain McDonnell Douglas Model DC-9-80 series airplanes 
and Model MD-88 airplanes series airplanes, was published in the 
Federal Register on October 4, 2000 (65 FR 59146). The action proposed 
to require, among other actions, repetitive dye penetrant and magnetic 
particle inspections to detect cracks of the main landing gear (MLG) 
pistons; repair and replacement of discrepant parts; and installation 
of a preventative modification; as applicable. The action also proposed 
an optional terminating action for certain MLG pistons.

Comments Received

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Request To Revise Note 1 of the Proposed AD

    One commenter request that the following sentence be added to Note 
1 of the proposed AD: ``Modification per previous revisions of the 
referenced service bulletin or dispositions from the manufacturer that 
occurred prior to the effective date of the AD comply with the AD.''
    The FAA partially agrees. We do not agree to include the sentence 
suggested by the commenter. However, as discussed below, we have 
included new notes in the final rule to give operators credit for 
accomplishing the preventative modification before the effective date 
of this AD.

Request To Give Credit for Preventative Modifications Accomplished 
Previously

    One commenter requests that operators be given credit for 
accomplishing the preventative modification per the original version, 
or Revisions 01 through 03 of McDonnell Douglas Service Bulletin MD80-
32-277, or procedures developed and analyzed by Boeing and approved by 
the FAA before the effective date of the AD. The commenter notes that 
Revision 04 of Service Bulletin MD80-32-277 (referenced as the 
appropriate source of service information for the requirements of this 
AD) contains procedures for wet grinding and flap shot peening, which 
were not recommended in the previous revisions of the service bulletin.
    Two other commenters request that the applicability of paragraph 
(e)(2)(i) of the proposed AD include any MLG piston modified before the 
effective date of the AD per the original version, or Revisions 01 
through 03 of McDonnell Douglas Service Bulletin MD80-32-277, or 
Service Rework Drawing SR08320081.
    One of the commenters notes that one of the paragraphs in the 
Discussion section of the proposed AD states ``Operators should note 
that, although the service bulletin specifies that the manufacturer may 
be contacted for disposition of certain repair conditions, this 
proposal would require the repair of those conditions to be 
accomplished per a method approved by the FAA. The commenter requests 
that it be revised to ``* * * certain repair conditions, for all 
repairs performed after the effective date of this AD, this proposed AD 
* * * .''
    The FAA partially agrees. We find that modification of any MLG 
piston or replacement with a modified MLG per the original version, and 
Revisions 1 through 4 of the referenced service bulletin, Service 
Rework Drawing SR08320081, or any FAA-approved preventative 
modification to MLG pistons, before the effective date of this AD, is 
considered acceptable for compliance with the preventative modification 
requirements of paragraphs (a)(3), (b)(1)(iii), (b)(2), and (c)(1) of 
this AD, and with the replacement requirements of paragraphs (c)(2) and 
(d)(1) of this AD. Therefore, we have included new notes in the final 
rule to clarify this point. With the inclusion of these new notes, we 
find that the applicability of paragraph (e)(2)(i) of the final rule 
does not need to be changed. We also find that a revision to the 
Discussion section, as suggested by the commenter, is not necessary 
because that section does not reappear in the final rule.

Request To Include Reidentified Part Number

    Two commenters request that paragraph (e) of the proposed AD also 
reference the part number (P/N) for MLG pistons that were modified and 
reidentified as P/N SR09320081-3 through SR09320081-13 inclusive, 
depending on its corresponding original identity. One of the commenters 
states that it tracks the MLG pistons by the applicable ``SR'' part 
number, which are listed in McDonnell Douglas Service Bulletin MD80-32-
277, Revisions 01 through 04.
    The FAA agrees that the affected MLG piston, P/N 5935347-1 through 
5935347-509 inclusive, identified in paragraph (e) of the AD, have been 
modified and reidentified as P/N SR09320081-3 through SR09320081-13 
inclusive. We have revised paragraph (e) of the final rule to clarify 
this point.

Request For Clarification of Applicability of Paragraph (e)(2)(ii) of 
the Proposed AD

    The applicability of paragraph (e)(2)(ii) of the proposed AD reads 
``For any MLG piston that has been modified prior to the effective date 
of this AD.'' One commenter interprets this to mean pistons modified 
prior to December 7, 1999 (the issuance date of Revision 04 of 
McDonnell Douglas Service Bulletin MD80-32-277). The commenter states 
that it is reasonable to assume that some pistons may have been 
modified by Revision 04 of the referenced service bulletin since its 
issuance in December 1999.
    From this comment, the FAA infers that the commenter is requesting 
that the applicability of paragraph (e)(2)(ii) of the proposed AD be 
clarified. We agree that clarification is necessary. The commenter is 
incorrect in its interpretation that the applicability of paragraph 
(e)(2)(ii) of the AD refers to MLG pistons modified per Revision 04 of 
McDonnell Douglas Service Bulletin MD80-32-277 prior to December 7, 
1999. Our intent was that paragraph (e)(2)(ii) of the AD be applicable 
to ``For any MLG piston that has been modified

[[Page 23842]]

per service information other than Revision 04 of McDonnell Douglas 
Service Bulletin MD80-32-277 and not inspected per Revision 04 of the 
service bulletin prior to the effective date of this AD.'' We have 
revised paragraph (e)(2)(ii) of the final rule accordingly to clarify 
this point.

Requests To Give Credit for Repetitive Inspections Since Modification

    Several commenters request that the FAA give credit to operators 
that are doing repetitive inspections every 2,500 landings since 
modification of the MLG pistons per McDonnell Douglas Service Bulletin 
MD80-32-277, Revision 04, dated December 7, 1999, for the initial 
inspections required by paragraph (e)(2)(ii) of the proposed AD and the 
repetitive inspections required by paragraph (f) of the proposed AD. 
Two commenters also state that paragraph (h)(2) of the proposed AD has 
a similar requirement and request that paragraph (h)(2) of the proposed 
AD also be revised.
    Another commenter states that, based on its service history, any 
MLG piston that has been inspected every 2,500 landings provides an 
equivalent level of safety. The commenter has no objection to the 
proposed initial compliance time of within 1,500 landings or 12 months 
after the effective date of this AD for MLG pistons that have not been 
inspected.
    The FAA does not consider that a change, as requested by the 
commenters, to the final rule is necessary. Operators are given credit 
for work previously performed by means of the phrase in the 
``Compliance'' section of the AD that states, ``Required as indicated, 
unless accomplished previously.'' Therefore, in the case of paragraphs 
(f) and (h)(2) of this AD, if the required inspection has been 
accomplished prior to the effective date of this AD, this AD does not 
require that it be repeated. However, this AD does require that 
repetitive inspections be conducted thereafter at intervals not to 
exceed 2,500 landings (if no cracking is detected, as specified in 
paragraphs (f) and (i) of the final rule), and that other follow-on 
actions be accomplished when indicated.

Request To Revise A Certain Compliance Time in Paragraph (f) of the 
Proposed AD

    Several commenters request that the compliance time of ``prior to 
the accumulation of 30,000 or more total landings on the MLG piston'' 
specified in paragraph (f) of the proposed AD be changed to ``within 
30,000 landings since modification of the MLG.'' One of the commenters 
states that the subject compliance time of paragraph (f) of the 
proposed AD conflicts with paragraph (a)(3) of the proposed AD, which 
requires the preventative modification of certain MLG pistons (non-
modified) that have accumulated 30,000 or more total landings to be 
done ``within 2 years or 5,000 landings on the MLG piston after the 
effective date of this AD.'' In this scenario, the commenter contends 
that a non-modified piston has an extended service allowance and 
modified pistons have been penalized.
    Another commenter states that the proposed compliance time 
conflicts with the requirements of paragraphs (b)(1)(iii) and (e)(2) of 
the proposed AD. Paragraph (b)(1)(iii) of the proposed AD requires the 
preventative modification ``prior to the accumulation of 30,000 or more 
total landings on the MLG piston.'' Paragraph (e)(2) of the proposed AD 
requires dye penetrant and magnetic particle inspections for any MLG 
piston that has accumulated less than 30,000 landings since 
accomplishment of the modification.
    It was the FAA's intent that the replacement required by paragraph 
(f) of the proposed AD be accomplished within 30,000 landing since 
modification of the MLG. Therefore, we agree with the commenters to 
revise the compliance time of paragraph (f) of the final rule from 
``prior to the accumulation of 30,000 or more total landings on the MLG 
piston'' to ``within 30,000 landings since modification of the MLG'' 
and have revised the final rule accordingly.

Request To Revise Phrase ``Since Date of Manufacture''

    One commenter requests that the phrase ``since date of 
manufacture'' be revised to ``since date of installation'' in 
paragraphs (h)(1), (h)(2), and (h)(3) of the proposed AD. The commenter 
states that industry's standard for tracking safe-life landing gear 
components is total landings accumulated from the date of installation, 
not the date of manufacture.
    The FAA does not agree. Because MLG pistons can be taken off 
airplanes and sold to other operators, there potentially could be 
multiple installations. Operators may misinterpret ``date of 
installation'' to mean that every time a MLG piston is installed, the 
number of landings returns to zero. Therefore, we find ``date of 
manufacture'' (i.e., since new) to be the correct phrase.

Request To Reference Correct Service Bulletin for Optional Terminating 
Action

    Several commenters request that paragraph (l) of the proposed AD be 
revised to reference McDonnell Douglas Service Bulletin MD80-32-309, 
which was issued by Boeing on January 31, 2000, instead of McDonnell 
Douglas Service Bulletin MD80-32-277, Revision 04, dated December 7, 
1999. One commenter states that Service Bulletin MD80-32-277 does not 
reference any configuration beyond part number (P/N) 5935347-511 for 
replacement of prior configurations. The commenter also states that 
Service Bulletin MD80-32-309 specifies that MLG piston, P/N 5935347-
517, is an approved configuration for closing action, and that it is an 
FAA-approved alternative method of compliance for both AD's 96-19-09 
and 99-13-07.
    The FAA agrees. We have reviewed McDonnell Douglas Service Bulletin 
MD80-32-277, Revision 04, dated December 7, 1999, and acknowledge that 
it does not describe procedures for replacement of any MLG piston with 
a MLG piston, P/N 5935347-517. The correct service information for 
accomplishing the replacement specified in paragraph (l) of this AD is 
McDonnell Douglas Service Bulletin MD80-32-309, dated January 31, 2000. 
We have revised paragraph (l) of the final rule accordingly.
    Operators should note that Service Bulletin MD80-32-309 also 
describes procedures for replacement of the MLG piston due to cracking 
near the radius of the jackball fitting. However, this proposed AD does 
not address the actions associated with the jackball fitting. We may 
consider issuing a separate rulemaking action to supersede AD 99-13-07.

Request To Include Inspection of Jackball Fitting

    One commenter requests that the proposed AD require an inspection/
rework of the aft torque link lug and inspection of the jackball 
fitting. The commenter provided no explanation for its request. The FAA 
does not agree. As discussed above, the FAA may issue a separate 
rulemaking action to address any identified unsafe condition associated 
with the jackball fitting.

Question About How To Determine the Inspection Interval and Imposed 
Life Limit

    One commenter asks how to determine the inspection interval and the 
imposed life limit for MLG pistons that were previously modified per

[[Page 23843]]

McDonnell Douglas Service Bulletin MD80-32-277, when it cannot 
determine the times and cycles accumulated at the time of modification.
    The FAA finds that, if the cycle count of the MLG piston cannot be 
determined at the time of modification, operators should work with an 
appropriate FAA Principal Maintenance Inspector (PMI), the Manager of 
the Los Angeles Aircraft Certification Office (ACO), and the airplane 
manufacturer to resolve the issue.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 1,200 Model DC-9-80 series airplanes and 
Model MD-88 airplanes of the affected design in the worldwide fleet. 
The FAA estimates that 700 airplanes of U.S. registry will be affected 
by this AD.
    Should an operator be required to do the dye penetrant and magnetic 
particle inspections, it will take approximately 2 work hours per MLG 
piston to accomplish the inspections, at an average labor rate of $60 
per work hour. Based on these figures, the cost impact of these 
inspections required by this AD on U.S. operators is estimated to be 
$120 per MLG piston.
    Should an operator be required to do the preventative modification, 
it will take approximately 6 work hours per MLG piston to accomplish 
the inspections, at an average labor rate of $60 per work hour. Based 
on these figures, the cost impact of these inspections required by this 
AD on U.S. operators is estimated to be $360 per MLG piston.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.
    Should an operator elect to accomplish the optional terminating 
action that is provided by this AD action, it would take approximately 
31 work hours per MLG piston to accomplish it, at an average labor rate 
of $60 per work hour. The cost of required parts would be approximately 
$107,070 per MLG piston. Based on these figures, the cost impact of the 
optional terminating action would be $108,930 per MLG piston.

Regulatory Impact

    The regulations adopted herein will not have a substantial direct 
effect 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, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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 removing amendment 39-9756 (61 FR 
48617, September 16, 1996), and by adding a new airworthiness directive 
(AD), amendment 39-12225, to read as follows:

2001-09-18  McDonnell Douglas: Amendment 39-12225. Docket 99-NM-164-
AD. Supersedes AD 96-19-09, Amendment 39-9756.

    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 04, dated December 7, 1999; 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 (m)(1) 
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:

For Airplanes on Which Certain Pistons Have Not Been Modified: 
Inspections

    (a) For airplanes on which any MLG piston, part number (P/N) 
5935347-1 through 5935347-509 inclusive, has NOT been modified: Do 
the actions specified in paragraph (a)(1), (a)(2), or (a)(3) of this 
AD, as applicable, per the Accomplishment Instructions of McDonnell 
Douglas Service Bulletin MD80-32-277, Revision 04, dated December 7, 
1999.
    (1) For any MLG piston that has accumulated less than 5,000 
total landings since date of manufacture: Prior to the accumulation 
of 5,000 total landings on the MLG piston, or within 12 months after 
the effective date of this AD, whichever occurs later, do dye 
penetrant and magnetic particle inspections to detect cracks of the 
MLG pistons.
    (2) For any MLG piston that has accumulated 5,000 or more total 
landings since date of manufacture, but less than 30,000 total 
landings since date of manufacture: Within 1,500 landings on the MLG 
piston or 12 months after the effective date of this AD, whichever 
occurs later, do dye penetrant and magnetic particle inspections to 
detect cracks of the MLG pistons.
    (3) For any MLG piston that has accumulated 30,000 or more total 
landings since date of manufacture: Within 2 years or 5,000 landings 
on the MLG piston after the effective date of this AD, whichever 
occurs first, do the preventative modification (including 
inspections; corrective actions, if necessary; wet grind rework 
area; flap shot peen rework area; and reidentify the MLG

[[Page 23844]]

pistons); except as required by paragraph (k) of this AD. Following 
accomplishment of the preventative modification, do the actions 
specified in paragraph (e) at the time indicated in that paragraph.

    Note 2: Modification of the MLG piston per the original version, 
and Revisions 01 through 04 of McDonnell Douglas Service Bulletin 
MD80-32-277, Service Rework Drawing SR08320081, or any FAA-approved 
preventative modification to MLG pistons before the effective date 
of this AD, is considered acceptable for compliance with the 
preventative modification requirements of paragraphs (a)(3), 
(b)(1)(iii), (b)(2), and (c)(1) of this AD.

For Airplanes on Which Certain Pistons Have Not Been Modified: 
Condition 1 (No Crack)

    (b) If no crack is found during any inspection required by 
either paragraph (a)(1) or (a)(2) of this AD, do the actions 
specified in either paragraph (b)(1) or (b)(2) of this AD.
    (1) Condition 1, Option 1. Do the actions specified in either 
paragraph (b)(1)(i) or (b)(1)(ii) of this AD, and in paragraph 
(b)(1)(iii) of this AD.
    (i) Repeat the inspections required by either paragraph (a)(1) 
or (a)(2) of this AD thereafter at intervals not to exceed 1,500 
landings until the permanent modification required by paragraph 
(b)(1)(iii) of this AD has been done.
    (ii) Before further flight, do the flap shot peening per 
McDonnell Douglas Service Bulletin MD80-32-277, Revision 04, dated 
December 7, 1999. Repeat the inspections required by either 
paragraph (a)(1) or (a)(2) of this AD thereafter at intervals not to 
exceed 2,500 landings until the permanent modification required by 
paragraph (b)(1)(iii) of this AD has been done.
    (iii) Prior to the accumulation of 30,000 or more total landings 
on the MLG piston, do the preventative modification (including 
inspections; corrective actions, if necessary; wet grind rework 
area; flap shot peen rework area; and reidentify the MLG pistons), 
per the Accomplishment Instructions of McDonnell Douglas Service 
Bulletin MD80-32-277, Revision 04, dated December 7, 1999; except as 
required by paragraph (k) of this AD. Accomplishment of the 
permanent modification stops the repetitive inspection requirements 
of paragraphs (b)(1)(i) and (b)(1)(ii) of this AD. Following 
accomplishment of the preventative modification, do the actions 
specified in paragraph (e) at the time indicated in that paragraph.
    (2) Condition 1, Option 2. Before further flight, do the 
preventative modification (including inspections; corrective 
actions, if necessary; wet grind rework area; flap shot peen rework 
area; and reidentify the MLG pistons) per Condition 1, Option 2, of 
the Accomplishment Instructions of McDonnell Douglas Service 
Bulletin MD80-32-277, Revision 04, dated December 7, 1999; except as 
required by paragraph (k) of this AD. Following accomplishment of 
the preventative modification, do the actions specified in paragraph 
(e) at the time indicated in that paragraph.

For Airplanes on Which Certain Pistons Have Not Been Modified: 
Condition 2 (Any Crack Within Limits)

    (c) If any crack is found during any inspection required by 
either paragraph (a)(1) or (a)(2) of this AD, and that crack is 
within the limits specified in McDonnell Douglas Service Bulletin 
MD80-32-277, Revision 04, dated December 7, 1999, before further 
flight, do the action(s) specified in either paragraph (c)(1) or 
(c)(2) of this AD.
    (1) Do the preventative modification (including inspections; 
corrective actions, if necessary; wet grind rework area; flap shot 
peen rework area; and reidentify the MLG pistons) per the 
Accomplishment Instructions of the service bulletin; except as 
required by paragraph (k) of this AD. Following accomplishment of 
the preventative modification, do the actions specified in paragraph 
(e) or (h) of this AD, as applicable, at the time indicated in that 
paragraph.
    (2) Replace the MLG piston with a new or serviceable MLG piston 
per the service bulletin. Following accomplishment of the 
replacement, do the actions specified in paragraph (a), (e), or (h) 
of this AD, as applicable, at the time indicated in that paragraph.

    Note 3: Replacement of the MLG piston with a modified MLG per 
the original version, and Revisions 01 through 04 of McDonnell 
Douglas Service Bulletin MD80-32-277, Service Rework Drawing 
SR08320081, or any FAA-approved preventative modification to MLG 
pistons before the effective date of this AD, is considered 
acceptable for compliance with the replacement requirements of 
paragraphs (c)(2) and (d)(1) of this AD.

For Airplanes on Which Certain Pistons Have Not Been Modified: 
Condition 3 (Any Crack Outside Limits)

    (d) If any crack is found during any inspection required by 
either paragraph (a)(1) or (a)(2) of this AD that is outside the 
limits specified in McDonnell Douglas Service Bulletin MD80-32-277, 
Revision 04, dated December 7, 1999, before further flight, do the 
action(s) specified in paragraph (d)(1) or (d)(2) of this AD.
    (1) Condition 3, Option 1. Replace the MLG piston with a new or 
serviceable MLG piston per the service bulletin. Following 
accomplishment of the replacement, do the actions specified in 
paragraph (a), (e), or (h) of this AD, as applicable, at the time 
indicated in that paragraph.
    (2) Condition 3, Option 2. Repair per a method approved by the 
Manager, Los Angeles Aircraft Certification Office (ACO), FAA.

For Airplanes on Which Certain Pistons Have Been Modified: Replacement 
or Inspections and Corrective Actions, If Necessary

    (e) For airplanes on which any MLG piston, part number (P/N) 
5935347-1 through 5935347-509 inclusive, has been modified and 
reidentified as P/N SR09320081-3 through SR09320081-13 inclusive:
    (1) For any MLG piston that has accumulated 30,000 or more 
landings since accomplishment of the modification: Within 6 months 
after the effective date of this AD, replace the MLG piston with a 
new or serviceable MLG piston per the service bulletin. Following 
accomplishment of the replacement, do the actions specified in 
paragraph (a), (e), or (h) of this AD, as applicable, at the time 
indicated in that paragraph.
    (2) For any MLG piston that has accumulated less than 30,000 
landings since accomplishment of the modification: Do dye penetrant 
and magnetic particle inspections to detect cracks of the MLG 
pistons, per the Accomplishment Instructions of McDonnell Douglas 
Service Bulletin MD80-32-277, Revision 04, dated December 7, 1999; 
at the applicable time(s) specified in paragraph (e)(2)(i) or 
(e)(2)(ii) of this AD.
    (i) For any MLG piston that has been modified per paragraph 
(a)(3), (b)(1)(iii), (b)(2), or (c)(1) of this AD, or that has been 
replaced with a modified MLG piston per paragraph (c)(2) or (d)(1) 
of this AD: Inspect within 2,500 landings following accomplishment 
of the modification or replacement with a modified MLG piston.
    (ii) For any MLG piston that has been modified per service 
information other than Revision 04 of McDonnell Douglas Service 
Bulletin MD80-32-277 and not inspected per Revision 04 of the 
service bulletin prior to the effective date of this AD: Inspect 
within 1,500 landings or 12 months after the effective date of this 
AD, whichever occurs later.
    (f) If no crack is found during any inspection required by 
paragraph (e)(2) of this AD, repeat the dye penetrant and magnetic 
particle inspections required by paragraph (e)(2) of this AD 
thereafter at intervals not to exceed 2,500 landings. Within 30,000 
landings since modification of the MLG piston, replace the MLG 
piston with a new or serviceable MLG piston per the Accomplishment 
Instructions of McDonnell Douglas Service Bulletin MD80-32-277, 
Revision 04, dated December 7, 1999. Following accomplishment of the 
replacement, do the actions specified in paragraph (a), (e), or (h) 
of this AD, as applicable, at the time indicated in that paragraph.
    (g) If any crack is found during any inspection required by 
paragraph (e)(2) of this AD, before further flight, do the action(s) 
specified in either paragraph (d)(1) or (d)(2) of this AD.

For Airplanes on Which A Certain Piston Has Been Installed:

    (h) For airplanes on which any MLG piston, P/N 5935347-511, has 
been installed: Do the actions specified in paragraph (h)(1), 
(h)(2), or (h)(3) of this AD, as applicable, per the Accomplishment 
Instructions of McDonnell Douglas Service Bulletin MD80-32-277, 
Revision 04, dated December 7, 1999.
    (1) For any MLG piston that has accumulated less than 5,000 
total landings since date of manufacture: Prior to the accumulation 
of 5,000 total landings on the MLG piston, or within 12 months after 
the effective date of this AD, whichever occurs later, do dye 
penetrant and magnetic particle

[[Page 23845]]

inspections to detect cracks of the MLG pistons.
    (2) For any MLG piston that has accumulated 5,000 or more total 
landings since date of manufacture, but less than 30,000 total 
landings since date of manufacture: Within 1,500 landings on the MLG 
piston or 12 months after the effective date of this AD, whichever 
occurs later, do dye penetrant and magnetic particle inspections to 
detect cracks of the MLG pistons.
    (3) For any MLG piston that has accumulated 30,000 or more total 
landings since date of manufacture: Within 6 months after the 
effective date of this AD, replace the MLG piston with a new or 
serviceable MLG piston per the service bulletin. Following 
accomplishment of the replacement, do the actions specified in 
paragraph (a), (e), or (h) of this AD, as applicable, at the time 
indicated in that paragraph.
    (i) If no crack is found during any inspection required by 
either paragraph (h)(1) or (h)(2) of this AD, repeat the dye 
penetrant and magnetic particle inspections required by either 
paragraph (h)(1) or (h)(2) of this AD thereafter at intervals not to 
exceed 2,500 landings. Prior to the accumulation of 30,000 or more 
total landings on the MLG piston, do the actions specified in 
paragraph (d)(1) of this AD.
    (j) If any crack is found during any inspection required by 
either paragraph (h)(1) or (h)(2) of this AD, before further flight, 
do the action(s) specified in either paragraph (d)(1) or (d)(2) of 
this AD.

Exception to Actions Referenced in Service Bulletin

    (k) If any discrepancy is found during any inspection while 
accomplishing the preventative modification required by this AD, 
prior to further flight, do applicable corrective action(s) per 
McDonnell Douglas Service Bulletin MD80-32-277, Revision 04, dated 
December 7, 1999. If the service bulletin specifies to contact the 
manufacturer for appropriate action: Prior to further flight, repair 
in accordance with a method approved by the Manager, Los Angeles 
ACO. For a repair method to be approved by the Manager, Los Angeles 
ACO, as required by this paragraph, the Manager's approval letter 
must specifically reference this AD.

Optional Terminating Action

    (l) Replacement of any MLG piston with a new MLG piston, P/N 
5935347-517, per McDonnell Douglas Service Bulletin MD80-32-309, 
dated January 31, 2000, constitutes terminating action for the 
requirements of this AD for that MLG piston.

Alternative Methods of Compliance

    (m)(1) 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. 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 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (2) Alternative methods of compliance, approved previously in 
accordance with AD 96-19-09, amendment 39-9756, are approved as 
alternative methods of compliance with this AD.

Special Flight Permits

    (n) 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.

Incorporation by Reference

    (o) Except as provided by paragraphs (d)(2), (k), and (l) of 
this AD, the actions shall be done in accordance with McDonnell 
Douglas Service Bulletin MD80-32-277, Revision 04, dated December 7, 
1999. This incorporation by reference was approved by the Director 
of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 
part 51. Copies may be obtained from Boeing Commercial Aircraft 
Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, 
California 90846, Attention: Data and Service Management, Dept. C1-
L5A (D800-0024). Copies may be inspected at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 
at the FAA, Los Angeles Aircraft Certification Office, 3960 
Paramount Boulevard, Lakewood, California; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

Effective Date

    (p) This amendment becomes effective on June 14, 2001.

    Issued in Renton, Washington, on May 3, 2001.
Lirio Liu Nelson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-11674 Filed 5-9-01; 8:45 am]
BILLING CODE 4910-13-P