[Federal Register Volume 60, Number 162 (Tuesday, August 22, 1995)]
[Rules and Regulations]
[Pages 43517-43519]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-19652]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-NM-121-AD; Amendment 39-9334; AD 95-17-05]


Airworthiness Directives; Airbus Model A310 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all Airbus Model A310 series airplanes, that requires 
inspections to detect loose self-locking nuts and damaged cotter pins 
on the actuating cylinder to drag strut attachment of the left- and 
right-hand main landing gear (MLG), and correction of discrepancies. 
This amendment also provides an optional terminating action for the 
repetitive inspections. This amendment is prompted by reports of loose 
nuts and sheared cotter pins found on in-service airplanes. The actions 
specified by this AD are intended to prevent an undampened free fall of 
the left- and right-hand MLG, which subsequently could lead to the 
inability to retract the MLG and damage to other airplane systems.

DATES: Effective September 21, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 21, 1995.

ADDRESSES: The service information referenced in this AD may be 
obtained from Messier Services, 45635 Willow Pond Plaza, Sterling, 
Virginia 20164. 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: Tim Backman, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2797; fax (206) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to all Airbus Model A310 series 
airplanes was published in the Federal Register on November 19, 1993 
(58 FR 61037). That action proposed to require repetitive inspections 
to detect loose self-locking nuts and damaged cotter pins on the 
actuating cylinder to drag strut attachment of the left- and right-hand 
main landing gear (MLG). That action also proposed to require 
replacement of loose nuts with new washers and new nuts, and torque 
tightening the nuts; replacement of damaged cotter pins with new cotter 
pins; and submission of inspection reports.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter supports the proposed rule.
    Certain commenters request that the proposed rule be revised to 
cite the latest revision of Messier Bugatti Airbus A310 Service 
Bulletin 470-32-744 as an additional source of service information. The 
FAA concurs. Since the issuance of the proposed rule, Messier Bugatti 
(the manufacturer of the MLG assembly) has issued Revision 1 of Messier 
Bugatti Airbus A310 Service Bulletin 470-32-744, dated January 13, 
1994. This revised service bulletin is essentially identical to the 
original version and does not entail any additional work. Therefore, 
the final rule has been revised to reference Revision 1 of the service 
bulletin as an additional source of service information.
    Three commenters request that the FAA revise the proposal to 
reference the accomplishment of the modification procedures described 
in Messier Bugatti Airbus A310 Service Bulletin 470-32-760 as a 
terminating modification for the repetitive inspection requirements. 
One of these commenters states that the modification described in this 
service bulletin includes a new hinge pin design that will preclude the 
previously identified problems.
    The FAA concurs. Since issuance of the proposed rule, Messier 
Bugatti has issued Airbus A310 Service Bulletin 470-32-760, dated 
December 31, 1993, as revised by Change Notice 1, dated January 28, 
1994. This service bulletin describes procedures for modification of 
the actuating cylinder/drag strut attachment of the MLG. The 
modification entails modifying the greasing duct to enable simultaneous 
rotation of the duct and cupel. The modification also entails modifying 
the anti-warping washer to provide rotation play with the actuating 
cylinder hinge pin. The modification will eliminate the risk of rupture 
of the cotter pin. Accomplishment of this modification eliminates the 
need for the repetitive inspections. Additionally, Airbus has issued 
Service Bulletin A310-32-2076, Revision 1, dated December 13, 1994, 
which references this Messier Bugatti service bulletin and is 
essentially identical to it.
    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, classified these service bulletins 
as mandatory. However, the FAA finds that the actions specified in the 
service bulletins may be provided as an optional terminating 
modification for the repetitive inspection requirements of the AD. The 
FAA has determined not to mandate the modification, since the 
inspection area is easily accessible, the discrepancies can be easily 
detected, and the inspection is easily performed without the need to 
remove any intervening structure. The FAA has added a new paragraph (c) 
to the final rule, which provides for this 

[[Page 43518]]
modification as optional terminating action for the required repetitive 
inspections.
    Additionally, since issuance of the notice, Airbus has issued 
Service Bulletin A310-32-2069, Revision 1, dated December 13, 1994, 
which references the Messier Bugatti Airbus A310 Service Bulletin 470-
32-744 that was cited in the proposal as the appropriate source of 
service information for procedures to inspect the cotter pins. The 
Airbus service bulletin is essentially identical to the corresponding 
Messier Bugatti service bulletin. The DGAC classified these service 
bulletins as mandatory in order assure the continued airworthiness of 
these airplanes in France and issued French airworthiness directive 93-
039-143(B)R2, dated December 7, 1994, in order to assure the continued 
airworthiness of these airplanes in France. The FAA has revised the 
final rule to include these Airbus service bulletins as additional 
sources of service information.
    The FAA has reviewed the requirements of the proposed paragraphs 
(a)(1) and (a)(2) and has determined that clarification is necessary. 
The actions proposed in those paragraphs were intended to be parallel 
to those recommended by the manufacturer in its referenced service 
bulletin. The intent of these requirements was to require the 
replacement of any loose nut and/or damaged cotter pin with a new nut, 
washer, and cotter pin; and to require the installation of a new cotter 
pin if no loose nut or no damaged cotter pin is found. However, as the 
proposed AD was worded, operators could incorrectly interpret the 
requirements as meaning that they must replace a loose nut only with a 
new nut, and replace a damaged cotter pin only with a new cotter pin. 
The operators also could incorrectly interpret the wording to mean that 
the installation of a new cotter pin would not be necessary if a loose 
nut or damaged cotter pin were found. In light of this, the FAA has 
determined that the wording of proposed paragraphs (a)(1) and (a)(2) 
must be revised to clarify its intent. These paragraphs of the final 
rule contain the clarifying wording.
    The FAA has recently reviewed the figures it has used over the past 
several years in calculating the economic impact of AD activity. In 
order to account for various inflationary costs in the airline 
industry, the FAA has determined that it is necessary to increase the 
labor rate used in these calculations from $55 per work hour to $60 per 
work hour. The economic impact information, below, has been revised to 
reflect this increase in the specified hourly labor rate.
    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.
    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 added to this final rule to clarify this long-standing 
requirement.
    The FAA estimates that 21 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 1 work hour per 
airplane to accomplish the required actions, and that the average labor 
rate is $60 per work hour. Based on these figures, the total cost 
impact of the AD on U.S. operators is estimated to be $1,260, or $60 
per airplane, per inspection cycle.
    The total cost impact figure discussed above is 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.
    Should an operator elect to accomplish the optional terminating 
action that is provided by this AD action, the number of hours required 
to accomplish it will be approximately 7 work hours per airplane, at an 
average labor rate of $60 per work hour. Required parts will cost 
approximately $1,968 per airplane. Based on these figures, the total 
cost impact of the optional terminating action on U.S. operators would 
be $2,388 per airplane.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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 USC 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

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

95-17-05  Airbus Industrie: Amendment 39-9334. Docket 93-NM-121-AD.

    Applicability: All Model A310 series airplanes, 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 (d) of this AD 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 

[[Page 43519]]
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 an undampened free fall of the left- and right-hand 
main landing gear (MLG), which subsequently could lead to the 
inability to retract the MLG and damage to other airplane systems, 
accomplish the following:
    (a) Within 60 days after the effective date of this AD, perform 
an inspection to detect loose self-locking nuts and damaged (sheared 
or marked) cotter pins on the actuating cylinder to drag strut 
attachment of the left- and right-hand MLG, in accordance with 
Messier Bugatti Airbus A310 Service Bulletin 470-32-744, dated March 
31, 1993, or Revision 1, dated January 13, 1994; or Airbus Service 
Bulletin A310-32-2069, Revision 1, dated December 13, 1994. Repeat 
this inspection thereafter at intervals not to exceed 500 landings.
    (1) If no nut is loose or no cotter pin is damaged, prior to 
further flight, install a new cotter pin, in accordance with the 
service bulletin. After replacement, continue to repeat the 
inspection at intervals not to exceed 500 landings
    (2) If any nut is loose or any cotter pin is damaged (sheared or 
marked), prior to further flight, replace the nut, washer, and 
cotter pin with a new nut, washer, and cotter pin; and torque 
tighten the nut; in accordance with the service bulletin. After 
replacement, continue to repeat the inspection at intervals not to 
exceed 500 landings.
    (b) Within 5 days after accomplishing the requirements of 
paragraph (a) this AD, report all inspection results, positive or 
negative, to Messier-Bugatti and Airbus Industrie in accordance with 
Messier-Bugatti Airbus A310 Service Bulletin 470-32-744, dated March 
31, 1993, or Revision 1, dated January 13, 1994. 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.
    (c) Modification of the actuating cylinder/drag strut attachment 
of the MLG, in accordance with Messier Bugatti Airbus A310 Service 
Bulletin 470-32-760, dated December 31, 1993, as revised by Change 
Notice 1, dated January 28, 1994; or Airbus Service Bulletin A310-
32-2076, Revision 1, dated December 13, 1994; constitutes 
terminating action for the repetitive inspection requirements of 
this AD.
    (d) 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, Standardization Branch, ANM-113, 
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, 
Standardization Branch, ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (e) 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.
    (f) The inspection shall be done in accordance in accordance 
with the following service bulletins, which contain the specified 
list of effective pages:

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                                                                      Revision level shown                      
   Service bulletin referenced and date             Page No.                 on page         Date shown on page 
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Messier Bugatti, 470-32-744, Mar. 31, 1993  1-7.....................  Original............  Mar. 31, 1993.      
Messier Bugatti, 470-32-744, Revision 1,    1-3, 5-6................  1...................  Jan. 13, 1994.      
 Jan. 13, 1994.                             4.......................  Original............  Mar. 31, 1993.      
Airbus, A310-32-2069, Revision 1, Dec. 13,  1-6, 8-9, 13............  1...................  Dec. 13, 1994.      
 1994.                                      7, 10-12................  Original............  July 29, 1993.      
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If accomplished, the modification shall be done in accordance with 
Messier Bugatti Airbus A310 Service Bulletin 470-32-760, dated 
December 31, 1993, as revised by Change Notice 1, dated January 28, 
1994; or Airbus Service Bulletin A310-32-2076, Revision 1, dated 
December 13, 1994, which contains the following list of effective 
pages:

------------------------------------------------------------------------
                                        Revision                        
              Page No.                level shown    Date shown on page 
                                        on page                         
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1-2, 4-8...........................  1............  Dec. 13, 1994.      
3, 9-11............................  Original.....  Dec. 14, 1993.      
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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 Messier Services, 45635 Willow Pond 
Plaza, Sterling, Virginia 20164. 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.
    (g) This amendment becomes effective on September 21, 1995.

    Issued in Renton, Washington, on August 3, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-19652 Filed 8-21-95; 8:45 am]
BILLING CODE 4910-13-U