[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
