[Federal Register Volume 63, Number 152 (Friday, August 7, 1998)]
[Proposed Rules]
[Pages 42286-42288]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-21104]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-192-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A320 Series Airplanes 
Equipped With a Bulk Cargo Door

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 all Airbus Model A320 series 
airplanes equipped with a bulk cargo door. This proposal would require 
repetitive inspections to detect fatigue cracking of the upper frame 
flanges; and repair, if necessary. This proposal also would require 
modification of the upper frame flanges of the bulk cargo door, which 
constitutes terminating action for 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 fatigue cracking 
of the upper frame flanges, which could result in reduced structural 
integrity of the airplane.

DATES: Comments must be received by September 8, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 97-NM-192-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from 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:

[[Page 42287]]

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 97-NM-192-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. 97-NM-192-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

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 all Airbus Model A320 series airplanes equipped 
with a bulk cargo door. The DGAC advises that, during full-scale 
fatigue testing on a Model A320 test article, fatigue cracking occurred 
at 89,000 simulated flights between frames 60 and 62 on the upper frame 
flanges. Such fatigue cracking, if not corrected, could result in 
reduced structural integrity of the airplane.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A320-53-1022, Revision 1, dated 
June 18, 1992, which describes procedures for repetitive high frequency 
eddy current inspections to detect fatigue cracking of the upper frame 
flanges.
    In addition, Airbus has issued Service Bulletin A320-53-1021, 
Revision 1, dated April 13, 1992, which describes procedures for a one-
time high frequency eddy current inspection to detect fatigue cracking 
of the upper frame flanges; repair, if necessary; and modification of 
the upper frame flanges. The repair entails stop drilling the cracked 
hole, and installing a new angle, shim, and plate on frame 60 and/or 
62. The modification involves reworking and flap peening the upper 
frame flanges of frames 60 and 62.
    Accomplishment of the repair or the modification would eliminate 
the need for the repetitive inspections described in Airbus Service 
Bulletin A320-53-1022, Revision 1.
    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition. The 
DGAC classified Airbus Service Bulletin A320-53-1022, Revision 1, as 
mandatory; approved Airbus Service Bulletin A320-53-1021, Revision 1; 
and issued French airworthiness directive 96-238-091(B), dated October 
23, 1996, in order to assure the continued airworthiness of these 
airplanes in France.

FAA's Conclusions

    This airplane model is manufactured in France and is type 
certificated for operation in the United States under the provisions of 
section 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 service bulletins described previously, 
except as discussed below.

Differences Between Proposed Rule and Foreign AD

    The proposed AD would differ from the parallel French airworthiness 
directive in that it would mandate the accomplishment of the 
terminating action for the repetitive inspections. The French 
airworthiness directive provides for that action as optional.
    Mandating the terminating action is based on the FAA's 
determination that long-term continued operational safety will be 
better assured by modifications or design changes to remove the source 
of the problem, rather than by repetitive inspections. Long-term 
inspections may not be providing the degree of safety assurance 
necessary for the transport airplane fleet. This, coupled with a better 
understanding of the human factors associated with numerous continual 
inspections, has led the FAA to consider placing less emphasis on 
inspections and more emphasis on design improvements. The proposed 
modification requirement is in consonance with these conditions.

Cost Impact

    The FAA estimates that 8 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 inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the inspection proposed by 
this AD on U.S. operators is estimated to be $480, or $60 per airplane, 
per inspection cycle.
    It would take approximately 4 work hours per airplane to accomplish 
the proposed modification, at an average labor rate of $60 per work 
hour. Based on these figures, the cost impact of the modification 
proposed by this AD on U.S. operators is estimated to be $1,920, or 
$240 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 substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if

[[Page 42288]]

promulgated, will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act. A copy of the draft regulatory 
evaluation prepared for this action is contained in the Rules Docket. A 
copy of it may be obtained by contacting the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (14 CFR part 39) as 
follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

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

Airbus Industrie: Docket 97-NM-192-AD.

    Applicability: Model A320 series airplanes, equipped with a bulk 
cargo door (Airbus Modification 20029), certificated in any 
category.

    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 fatigue cracking of the upper frame flanges, which 
could result in reduced structural integrity of the airplane, 
accomplish the following:
    (a) Prior to the accumulation of 20,000 total flight cycles, or 
within 1,200 flight cycles after the effective date of this AD, 
whichever occurs later: Perform a high frequency eddy current 
inspection to detect fatigue cracking of the upper frame flanges, in 
accordance with Airbus Service Bulletin A320-53-1022, Revision 1, 
dated June 18, 1992.
    (1) If no cracking is detected, accomplish either paragraph 
(a)(1)(i) or (a)(1)(ii) of this AD.
    (i) Repeat the eddy current inspection thereafter at intervals 
not to exceed 1,200 flight cycles until accomplishment of the 
requirements of paragraph (b) of this AD. Or
    (ii) Prior to further flight, modify the upper frame flanges, in 
accordance with Airbus Service Bulletin A320-53-1021, Revision 1, 
dated April 13, 1992. This modification constitutes terminating 
action for the requirements of this AD.
    (2) If any cracking is detected, prior to further flight, repair 
in accordance with Airbus Service Bulletin A320-53-1021, Revision 1, 
dated April 13, 1992. Accomplishment of the repair constitutes 
terminating action for the requirements of this AD.
    (b) Prior to the accumulation of 26,000 total flight cycles, or 
within 6,000 flight cycles after the effective date of this AD, 
whichever occurs later: Perform a high frequency eddy current 
inspection to detect fatigue cracking of the upper frame flanges, in 
accordance with Airbus Service Bulletin A320-53-1021, Revision 1, 
dated April 13, 1992.
    (1) If no cracking is detected, prior to further flight, modify 
the upper frame flanges, in accordance with the service bulletin. 
Accomplishment of this modification constitutes terminating action 
for the requirements of this AD.
    (2) If any cracking is detected, prior to further flight, repair 
in accordance with the service bulletin. Accomplishment of the 
repair constitutes terminating action for the requirements of this 
AD.
    (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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.
    (d) 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.

    Note 3: The subject of this AD is addressed in French 
airworthiness directive 96-238-091(B), dated October 23, 1996.

    Issued in Renton, Washington, on July 31, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-21104 Filed 8-6-98; 8:45 am]
BILLING CODE 4910-13-P