AD 2001-08-11

[Federal Register Volume 66, Number 81 (Thursday, April 26, 2001)]
[Rules and Regulations]
[Pages 20904-20907]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-9879]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-139-AD; Amendment 39-12188; AD 2001-08-11]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR42-200, -300, and 
-320 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to all Aerospatiale Model ATR42-300 and -320 series 
airplanes, that currently requires repetitive ultrasonic inspections to 
detect cracking of certain lugs on the main landing gear (MLG), 
replacement of cracked lugs with new or serviceable parts, and a 
follow-on inspection; and provides for an optional terminating action 
for the repetitive inspections. This amendment removes that terminating 
action and requires new repetitive inspections of the rubber sealant to 
detect shearing, and corrective action, if necessary. This action also 
requires new one-time visual and fluorescent penetrant inspections to 
detect discrepancies of certain lugs, and refurbishment of the MLG 
barrel and swing lever assemblies, which terminates the requirements of 
this AD. This action also revises the applicability of the existing AD. 
This amendment is prompted by issuance of mandatory continuing 
airworthiness information by a foreign civil airworthiness authority. 
The actions specified by this AD are intended to prevent discrepancies 
of the MLG barrel lower lugs, which could result in reduced structural 
integrity and possible collapse of the MLG.

DATES: Effective May 31, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 31, 2001.
    The incorporation by reference of certain other publications listed 
in the regulations was approved previously by the Director of the 
Federal Register as of March 7, 1997 (62 FR 7665, February 20, 1997).

ADDRESSES: The service information referenced in this AD may be 
obtained from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 
03, France. 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 Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, Washington, 
DC.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

[[Page 20905]]


SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 97-26-19, 
amendment 39-10262 (62 FR 66980, December 23, 1997), which is 
applicable to all Aerospatiale Model ATR42-300 and -320 series 
airplanes, was published in the Federal Register on November 28, 2000 
(65 FR 70815). That action proposed to remove the terminating action 
and require new repetitive inspections of the rubber sealant to detect 
shearing, and corrective action if necessary. That action also proposed 
to require new one-time visual and fluorescent penetrant inspections to 
detect discrepancies of certain lugs and refurbishment of the main 
landing gear (MLG) barrel and swing lever assemblies, which would 
terminate the requirements of the proposed AD. That action also 
proposed to revise the applicability of the existing AD to include 
Model ATR42-200 series airplanes.

Comments

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

Request To Extend Compliance Time for Refurbishment

    The commenter (the manufacturer of the subject MLG legs) requests 
an extension of the compliance time to refurbish the MLG legs, as 
specified in paragraphs (g) and (h) of the proposed AD. The commenter 
reports that those proposed compliance times have already passed for 
many of the affected airplanes. Approximately 70 MLG legs have not been 
refurbished. For certain airplanes, the proposed AD would require the 
MLG legs to be refurbished within the proposed 60-day grace period; for 
other airplanes, no grace period was provided. Furthermore, the 
refurbishment must be done by third-party maintenance vendors. They 
estimate that, based on current shop schedules and the availability of 
spare parts, it would take 36 months after December 2000 to refurbish 
all affected MLG legs in the U.S.
    The FAA concurs with the request to extend the compliance times to 
refurbish the MLG legs. In developing an appropriate compliance time, 
the FAA considered the safety implications, parts availability, and 
maintenance schedules for timely accomplishment of the refurbishment. 
In consideration of these factors, the FAA has determined that the 
revised compliance times (24 months for airplanes modified in 
accordance with Messier-Dowty Service Bulletin 631-32-133; 42 months 
for unmodified airplanes) represent an appropriate interval in which 
the refurbishment can be accomplished in a timely manner within the 
fleet and an adequate level of safety can be maintained. Paragraphs (g) 
and (h) have been revised accordingly in this final rule.

Clarification of Compliance Time for Sealant Inspection

    The FAA noted some incongruous compliance times specified in 
paragraph (e) of the proposed AD. Proposed paragraph (e)(1) referred to 
a repetitive interval of 300 landings, and proposed paragraph (e)(2) 
referred to immediate compliance for the corrective action. Both 
paragraphs conflict with the prior reference in paragraph (e) to a 400-
flight-hour repetitive interval. Paragraphs (e), (e)(1), and (e)(2) 
have been revised in this final rule to eliminate the conflicting 
requirements.

Conclusion

    After careful review of the available data, including the comment 
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 84 airplanes of U.S. registry that will be 
affected by this AD.
    The inspection that is currently required by AD 97-26-19, and 
retained in this AD, takes approximately 2 work hours per airplane to 
accomplish, at an average labor rate of $60 per work hour. Based on 
these figures, the cost impact of the currently required actions is 
estimated to be $120 per airplane, per inspection cycle.
    The new inspections and refurbishment required by this AD will take 
approximately 29 work hours per airplane, at an average labor rate of 
$60 per work hour. Required parts will cost approximately $4,822 per 
airplane. Based on these figures, the cost impact of the new 
requirements of this AD on U.S. operators is estimated to be $551,208, 
or $6,562 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.

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 39-10262 (62 FR 
66980, December 23, 1997), and by adding a new airworthiness directive 
(AD), amendment 39-12188, to read as follows:

2001-08-11  Aerospatiale: Amendment 39-12188. Docket 98-NM-139-AD. 
Supersedes AD 97-26-19, Amendment 39-10262.

    Applicability: Model ATR42-200, -300, and -320 series airplanes; 
certificated in any category; except airplanes that have been 
refurbished in accordance with Messier-Dowty Service Bulletin 631-
32-145, dated February 16, 1998.

[[Page 20906]]


    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (k)(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 detect and correct discrepancies of the main landing gear 
(MLG) barrel lower lugs, which could result in reduced structural 
integrity and possible collapse of the MLG, accomplish the 
following:

Ultrasonic Inspection

    (a) For airplanes on which the actions specified by Messier-
Dowty Service Bulletin 631-32-133, dated February 24, 1997, as 
revised by Change Notice No. 1, dated March 18, 1997, have not been 
accomplished prior to the effective date of this AD: Perform an 
ultrasonic inspection to detect fatigue cracks of the lower lugs of 
the barrel of the MLG, in accordance with Messier-Dowty Service 
Bulletin 631-32-132, dated January 21, 1997, at the applicable time 
specified in paragraph (a)(1), (a)(2), (a)(3), or (a)(4) of this AD.
    (1) For Model ATR42-300 and -320 series airplanes: Inspect 
within 2 years after the last overhaul or repair of the lower lugs 
of the barrel of the MLG; or within 60 days after March 7, 1997 (the 
effective date of AD 97-04-09, amendment 39-9933); whichever occurs 
later.
    (2) For Model ATR42-300 and -320 series airplanes: Inspect 
within 5 years after the installation of a new MLG barrel assembly, 
or within 60 days after January 7, 1998 (the effective date of AD 
97-26-19, amendment 39-10262); whichever occurs later.
    (3) For Model ATR42-200 series airplanes: Inspect within 2 years 
after the last overhaul or repair of the lower lugs of the barrel of 
the MLG, or within 60 days after the effective date of this AD, 
whichever occurs later.
    (4) For Model ATR42-200 series airplanes: Inspect within 5 years 
after the installation of a new MLG barrel assembly, or within 60 
days after the effective date of this AD, whichever occurs later.
    (b) If, during any inspection specified in paragraph (a) of this 
AD, no ultrasonic echo (as described in Messier-Dowty Service 
Bulletin 631-32-133, dated February 24, 1997, as revised by Change 
Notice No. 1, dated March 18, 1997) is detected, or if the echo is 
less than 20%: Except as required by paragraph (c) of this AD, 
repeat the ultrasonic inspection thereafter at intervals not to 
exceed 900 landings.
    (c) For airplanes that are subject to the repetitive inspection 
requirements of paragraph (b) of this AD: As of the effective date 
of this AD, repeat the inspection, as specified by Table 1 of this 
AD, until the requirements of paragraph (f) of this AD are 
accomplished. Table 1 is as follows:

                      Table 1.--Repetitive Interval
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   If the first ultrasonic inspection
 specified by paragraph (a) of this AD      Then repeat the ultrasonic
               was done--                          inspection--
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At least 24 months, and less than 42     Within 500 landings after the
 months, before the effective date of     first ultrasonic inspection,
 this AD.                                 or within 60 days after the
                                          effective date of this AD,
                                          whichever occurs later and
                                          thereafter at intervals not to
                                          exceed 500 landings.
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Less than 24 months before the           At intervals not to exceed 900
 effective date of this AD, or at any     landings, for a period not to
 time on or after the effective date of   exceed 24 months after the
 this AD.                                 first ultrasonic inspection of
                                          (a) of this AD; and thereafter
                                          at intervals not to exceed 500
                                          landings.
------------------------------------------------------------------------

    (d) If, during any inspection specified in paragraph (a) of this 
AD, the echo is greater than or equal to 20%: Prior to further 
flight, replace the MLG barrel assembly with a new or serviceable 
MLG barrel assembly, in accordance with Messier-Dowty Service 
Bulletin 631-32-132, dated January 21, 1997.
    (1) If the damaged barrel assembly is replaced with an 
overhauled or repaired assembly, within 2 years after installation 
of that overhauled or repaired part, accomplish the actions 
specified in paragraph (a) of this AD.
    (2) If the damaged barrel assembly is replaced with a new barrel 
assembly, within 5 years after installation of that new part, 
accomplish the actions specified in paragraph (a) of this AD.

Inspection of Sealant

    (e) For airplanes on which the actions specified by Messier-
Dowty Service Bulletin 631-32-133, dated February 24, 1997, as 
revised by Change Notice No. 1, dated March 18, 1997, have been 
accomplished prior to the effective date of this AD: Within 400 
flight hours after the effective date of this AD, perform a detailed 
visual inspection to detect discrepancies (including shearing or 
separation) of the rubber sealant between the bushings and the MLG 
barrel lower lugs, and between the bushing and the swinging lever 
lug, in accordance with Messier-Dowty Service Bulletin 631-32-144, 
dated January 19, 1998.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

    (1) If no discrepancy is detected, repeat the detailed visual 
inspection specified in paragraph (e) of this AD thereafter at 
intervals not to exceed 400 flight hours, until accomplishment of 
the actions required by paragraph (f) of this AD.
    (2) If any discrepancy is detected, prior to further flight, 
repeat the ultrasonic inspection and all applicable corrective 
actions specified by paragraphs (a), (b), and (d) of this AD.

Inspections and MLG Refurbishment

    (f) For all airplanes: At the applicable time specified by 
paragraph (g) or (h) of this AD, accomplish the actions required by 
paragraphs (f)(1) and (f)(2) of this AD, in accordance with Messier-
Dowty Service Bulletin 631-32-145, dated February 16, 1998, or 
Revision 1, dated May 31, 1999. Accomplishment of the inspections 
and refurbishment required by this paragraph constitutes terminating 
action for the requirements of this AD.
    (1) Perform a one-time detailed visual inspection and a one-time 
fluorescent penetrant inspection to detect discrepancies (cracks, 
corrosion, and material defects) of the barrel lower lugs (outboard 
and inboard).
    (i) If no discrepancy is found, prior to further flight, 
refurbish the lugs in accordance with the service bulletin.
    (ii) If any discrepancy is found, prior to further flight, 
refurbish the lugs in accordance with the service bulletin and 
repeat the detailed visual inspection and fluorescent penetrant 
inspection. If any discrepancy remains, prior to further flight, do 
the actions specified by either paragraph (f)(1)(ii)(A) or 
(f)(1)(ii)(B) of this AD.
    (A) Replace the damaged MLG barrel with a new or reconditioned 
barrel.
    (B) Repair in accordance with a method approved by either the 
Manager, International Branch, ANM-116, FAA, Transport Airplane 
Directorate; or the Direction Generale de l'Aviation Civile (DGAC) 
(or its delegated agent).
    (2) Refurbish the MLG (including restoring the protective 
treatments, installing new bushings, and installing new lubrication 
points of the MLG barrel and swinging lever assemblies).

[[Page 20907]]

Compliance Times for Inspections and Refurbishment

    (g) For airplanes on which the actions specified by Messier-
Dowty Service Bulletin 631-32-133, dated February 24, 1997, have not 
been accomplished prior to the effective date of this AD: Do the 
actions required by paragraph (f) of this AD within 42 months after 
the effective date of this AD.
    (h) For airplanes on which the actions specified by Messier-
Dowty Service Bulletin 631-32-133, dated February 24, 1997, have 
been accomplished prior the effective date of this AD: Do the 
actions required by paragraph (f) of this AD within 24 months after 
the effective date of this AD.

Reporting Requirement

    (i) At the applicable time specified by paragraph (i)(1) or 
(i)(2) of this AD, submit a report of the results (both positive and 
negative findings) of the initial inspections required by paragraphs 
(a) and (e) of this AD to Messier-Dowty, BP 10-78142 Velizy Cedex, 
France. 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.
    (1) For airplanes on which the inspections are accomplished 
after the effective date of this AD: Submit a report of each 
inspection within 10 days after performing the applicable 
inspection.
    (2) For airplanes on which the inspections have been 
accomplished prior to the effective date of this AD: Submit the 
report within 10 days after the effective date of this AD.

Spares

    (j) As of the effective date of this AD, no person shall install 
a bushing, part number D66349, on the MLG barrel and swinging lever 
assemblies on any airplane.

Alternative Methods of Compliance

    (k)(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, International Branch, ANM-116. 
Operators shall submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, International Branch, ANM-116.
    (2) Alternative methods of compliance approved previously in 
accordance with AD 97-26-19, amendment 39-10262, are approved as 
alternative methods of compliance with the applicable requirements 
of this AD.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (l) 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

    (m) Except as required by paragraph (f)(1)(ii)(B) of this AD: 
The actions must be done in accordance with Messier-Dowty Service 
Bulletin 631-32-132, dated January 21, 1997; Messier-Dowty Service 
Bulletin 631-32-144, dated January 19, 1998; Messier-Dowty Service 
Bulletin 631-32-145, dated February 16, 1998; and Messier-Dowty 
Service Bulletin 631-32-145, Revision 1, dated May 31, 1999; as 
applicable. Messier-Dowty Service Bulletin 631-32-145, Revision 1, 
dated May 31, 1999, contains the following list of effective pages:

------------------------------------------------------------------------
                                   Revision level
            Page No.               shown on page     Date shown on page
------------------------------------------------------------------------
1, 2, 9, 10.....................  1..............  May 31, 1999.
3-8, 11-46......................  Original.......  Feb. 16, 1998.
------------------------------------------------------------------------

    (1) The incorporation by reference of Messier-Dowty Service 
Bulletin 631-32-144, dated January 19, 1998; Messier-Dowty Service 
Bulletin 631-32-145, dated February 16, 1998; and Messier-Dowty 
Service Bulletin 631-32-145, Revision 1, dated May 31, 1999; is 
approved by the Director of the Federal Register in accordance with 
5 U.S.C. 552(a) and 1 CFR part 51.
    (2) The incorporation by reference of Messier-Dowty Service 
Bulletin 631-32-132, dated January 21, 1997, was approved previously 
by the Director of the Federal Register as of March 7, 1997 (62 FR 
7665, February 20, 1997).
    (3) Copies of any of these service bulletins may be obtained 
from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, 
France. Copies may be inspected at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

    Note 4: The subject of this AD is addressed in French 
airworthiness directive 1996-294(B) R4, dated March 10, 1999.

Effective Date

    (n) This amendment becomes effective on May 31, 2001.


    Issued in Renton, Washington, on April 16, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-9879 Filed 4-25-01; 8:45 am]
BILLING CODE 4910-13-P