[Federal Register Volume 65, Number 31 (Tuesday, February 15, 2000)]
[Proposed Rules]
[Pages 7465-7467]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-3533]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-343-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A319, A320, and A321 
Series 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 Airbus Model A319, A320, 
and A321 series airplanes. This proposal would require repetitive 
inspections of the sliding tube subassembly on the main landing gear 
(MLG) to detect cracks, and replacement of a cracked subassembly with a 
new subassembly. This proposal also would eventually require a more 
extensive, one-time inspection of the same area and corrective actions, 
if necessary; which would terminate the repetitive inspections. This 
proposal is prompted by issuance of mandatory continuing airworthiness 
information by a foreign civil airworthiness authority. The actions 
specified by the proposed AD are intended to prevent cracking of the 
MLG sliding tube subassembly, which could result in collapse of the 
MLG.

DATES: Comments must be received by March 16, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-343-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

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.

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 99-NM-343-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-114, Attention: Rules 
Docket No. 99-NM-343-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

[[Page 7466]]

Discussion

    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, notified the FAA that an unsafe 
condition may exist on certain Airbus Model A319, A320, and A321 series 
airplanes. The DGAC advises that, during a scheduled inspection of the 
main landing gear (MLG) on one airplane, two cracks were found in the 
base of the sliding tube. The cracks originated from the bore of the 
jacking dome bushing. The DGAC advises that a nondestructive test 
inspection may have been improperly performed causing local overheating 
between the jacking dome bushing and the sliding tube bore. This 
overheating increases the possibility of crack initiation. This 
condition, if not corrected, could result in collapse of the MLG.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A320-32-1189, dated December 23, 
1998, which describes procedures for visual inspections of the MLG 
sliding tube subassembly for cracks, and corrective action, if 
necessary. Two separate inspections are described. The service bulletin 
describes procedures for repetitive visual inspections of the sliding 
tube subassembly around the area between the jacking dome bushing and 
the high pressure inflation valve, and between the jacking dome bushing 
and the hole for the lower electrical harness assembly; and procedures 
for replacing a cracked sliding tube subassembly with a new 
subassembly. The service bulletin also describes procedures for removal 
of the jacking dome, bushing, and harness supports, and a one-time 
visual inspection to detect cracking of the sliding tube subassembly in 
the area where the jacking dome bushing was removed.
    Airbus has also revised the Aircraft Maintenance Manual to include 
cautions during accomplishment of the MLG nondestructive test 
inspection.
    Accomplishment of the actions specified in the service bulletin is 
intended to adequately address the identified unsafe condition. The 
DGAC classified the Airbus service bulletin as mandatory and issued 
French airworthiness directive 1999-358-137(B) R1, dated October 20, 
1999, in order to ensure the continued airworthiness of these airplanes 
in France.

FAA's Conclusions

    These airplane models are manufactured in France and are type 
certificated for operation in the United States under the provisions of 
Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the 
applicable bilateral airworthiness agreement. Pursuant to this 
bilateral airworthiness agreement, the DGAC has kept the FAA informed 
of the situation described above. The FAA has examined the findings of 
the DGAC, reviewed all available information, and determined that AD 
action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the Airbus service bulletins described 
previously, except as discussed below.

Differences Between NPRM and Service Bulletin/French Airworthiness 
Directive

    The proposed compliance times and repetitive intervals (stated in 
flight hours) differ from those recommended by the manufacturer's 
service bulletin (stated to coincide with operators' ``A'' and ``C'' 
checks). However, because regularly scheduled maintenance intervals 
such as ``A'' checks and ``C'' checks may vary from operator to 
operator, there would be no assurance that the inspections would be 
accomplished during the maximum intervals proposed by this AD designed 
to maintain an adequate level of safety within the fleet. The 
compliance times in the proposed AD and the French airworthiness 
directive agree.
    In addition, 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 in accordance with a 
method approved by either the FAA or the DGAC (or its delegated agent). 
In light of the type of repair that would be required to address the 
identified unsafe condition, and in consonance with existing bilateral 
airworthiness agreements, the FAA has determined that, for this 
proposed AD, a repair approved by either the FAA or the DGAC would be 
acceptable for compliance with this proposed AD.
    Further, the applicability of this proposed AD differs from that of 
the French airworthiness directive, which excludes airplanes on which 
(1) the MLG sliding tubes have never been removed, (2) the MLG sliding 
tubes have never received an NDT (NDT2) inspection, and (3) the MLG 
sliding tubes have received an NDT (NDT2) inspection with the attaching 
hardware and bushing removed from the sliding tube. Because these 
conditions may not be easily determined, the applicability of this 
proposed AD would be limited to airplanes on which Airbus Service 
Bulletin A320-32-1189 has not been accomplished.

Cost Impact

    The FAA estimates that 179 airplanes of U.S. registry would be 
affected by this proposed AD.
    It would take approximately 1 work hour per airplane to accomplish 
the proposed ``Part A'' (repetitive) inspection, at an average labor 
rate of $60 per work hour. Based on these figures, the cost impact of 
the Part A inspection proposed by this AD on U.S. operators is 
estimated to be $10,740, or $60 per airplane, per inspection cycle.
    It would take approximately 6 work hours per airplane to accomplish 
the proposed ``Part B'' (one-time) inspection, at an average labor rate 
of $60 per work hour. Based on these figures, the cost impact of the 
Part B inspection proposed by this AD on U.S. operators is estimated to 
be $64,440, or $360 per airplane.
    The cost impact figures discussed above are 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.

Regulatory Impact

    The regulations proposed herein would 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 proposal would not have federalism implications 
under Executive Order 13132.
    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

[[Page 7467]]

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:

Airbus: Docket 99-NM-343-AD.

    Applicability: Model A319, A320, and A321 series airplanes; 
manufacturer serial numbers through 0875 inclusive; certificated in 
any category; except those on which Airbus Service Bulletin A320-32-
1189, dated December 23, 1998, has not been accomplished.

    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 (c) 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 cracking of the sliding tube subassembly of the main 
landing gear (MLG), which could result in collapse of the MLG, 
accomplish the following:

Inspections

    (a) Within 500 flight hours after the effective date of this AD, 
perform a detailed visual inspection to detect cracking of the left-
hand and right-hand MLG sliding tube subassemblies, in accordance 
with paragraph 2.B.(1) of the Accomplishment Instructions of Airbus 
Service Bulletin A320-32-1189, dated December 23, 1998.
    (1) If no crack is found, repeat the inspection at intervals not 
to exceed 500 flight hours, until the requirements of paragraph (b) 
of this AD have been accomplished.
    (2) If any crack is found, prior to further flight, replace the 
sliding tube subassembly with a new subassembly, in accordance with 
the service bulletin. Thereafter, repeat the inspection at intervals 
not to exceed 500 flight hours, until the requirements of paragraph 
(b) of this AD have been accomplished.

    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.''


    (b) Within 15 months after the effective date of this AD: Remove 
the jacking dome, the stop washer, the jacking dome bushing, and the 
harness supports; and perform detailed visual inspections to detect 
discrepancies (including cracking of the left and right MLG sliding 
tube subassemblies, and overheat damage of the jacking dome 
bushing), in accordance with paragraph 2.B.(2) of the Accomplishment 
Instructions of Airbus Service Bulletin A320-32-1189, dated December 
23, 1998. Accomplishment of the requirements of this paragraph 
constitutes terminating action for the requirements of paragraph (a) 
of this AD.
    (1) If no discrepancy is found, prior to further flight, install 
a new stop washer and jacking dome bushing, in accordance with the 
service bulletin. No further action is required by this AD.
    (2) If any discrepancy is found, prior to further flight, repair 
in accordance with a method approved by the Manager, International 
Branch, ANM-116, FAA, Transport Airplane Directorate; or the 
Direction Generale de l'Aviation Civile (DGAC) (or its delegated 
agent). For a repair method to be approved by the Manager, 
International Branch, ANM-116, as required by this paragraph, the 
Manager's approval letter must specifically reference this AD.

Alternative Methods of Compliance

    (c) 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, 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, International 
Branch, ANM-116.

    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

    (d) 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.

    Note 4: The subject of this AD is addressed in French 
airworthiness directive 1999-358-137(B) R1, dated October 20, 1999.


    Issued in Renton, Washington, on February 9, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-3533 Filed 2-14-00; 8:45 am]
BILLING CODE 4910-13-U