[Federal Register Volume 63, Number 71 (Tuesday, April 14, 1998)]
[Proposed Rules]
[Pages 18156-18158]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-9759]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-194-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A320 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 A320 series 
airplanes. This proposal would require repetitive inspections to detect 
fatigue cracking on the connecting angle between frame 56 and the 
right-hand frame support at stringer 38; and replacement of the 
connecting angle, if necessary. This proposal also provides for an 
optional 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 detect and correct fatigue 
cracking on the connecting angle, which could result in reduced 
structural integrity of the airplane.

DATES: Comments must be received by May 14, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

[[Page 18157]]

Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 97-NM-194-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:

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-194-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-194-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 certain Airbus Model A320 series airplanes. The 
DGAC advises that, during full-scale testing on a Model A320 test 
article, fatigue cracks were found at 60,500 simulated flights on the 
connecting angle between frame 56 and the right-hand frame support at 
stringer 38. This condition, if not corrected, could result in reduced 
structural integrity of the airplane.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A320-53-1084, Revision 1, dated 
November 28, 1995, which describes procedures for repetitive visual 
inspections to detect fatigue cracking on the connecting angle between 
frame 56 and the right-hand frame support at stringer 38. In addition, 
Airbus has issued Service Bulletin A320-53-1011, dated December 9, 
1994, which describes procedures for replacement of the connecting 
angle with a new part, which would eliminate the need for the 
repetitive inspections described in Airbus Service Bulletin A320-53-
1084. Accomplishment of the actions specified in the service bulletins 
is intended to adequately address the identified unsafe condition.
    The DGAC classified Airbus Service Bulletin A320-53-1084, Revision 
1, as mandatory and issued French airworthiness directive 96-237-
090(B), dated October 23, 1996, and Erratum to French airworthiness 
directive 96-237-090(B), dated February 26, 1997, in order to assure 
the continued airworthiness of these airplanes in France. The DGAC has 
also approved Airbus Service Bulletin A320-53-1011.

FAA's Conclusions

    This airplane model is manufactured in France and is 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 service bulletins described previously, 
except as discussed below. This proposed AD also would provide for 
optional terminating action for the repetitive inspections.
    Operators should note that, in consonance with the findings of the 
DGAC, the FAA has determined that the repetitive inspections proposed 
by this AD can be allowed to continue in lieu of accomplishment of a 
terminating action. In making this determination, the FAA considers 
that, in this case, long-term continued operational safety will be 
adequately assured by accomplishing the repetitive inspections to 
detect fatigue cracking before it represents a hazard to the airplane.

Differences Between Proposed Rule and Service Bulletins

    Operators should note that, unlike the procedures described in 
Airbus Service Bulletin A320-53-1084, Revision 1, dated November 28, 
1995, this proposed AD would not permit further flight if cracks are 
detected on the connecting angle between frame 56 and the right-hand 
frame support at stringer 38. The FAA has determined that, because of 
the safety implications and consequences associated with such cracking, 
any subject connecting angle that is found to be cracked must be 
replaced with a new part prior to further flight.

Cost Impact

    The FAA estimates that 5 airplanes of U.S. registry would be 
affected by this proposed AD. It would take approximately 1 work hour 
per airplane to accomplish the inspection proposed by this AD, at an 
average labor rate of $60 per work hour. Based on this figure, the cost 
impact of the inspection proposed by this AD on U.S. operators is 
estimated to be $300, or $60 per airplane, per inspection cycle.
    The cost impact figure discussed above is 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.
    Should an operator elect to perform the optional terminating 
replacement proposed by this AD, it would take approximately 3 work 
hours per airplane to accomplish the modification,

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at an average labor rate of $60 per work hour. Required parts would 
cost $136 or $153 per airplane, depending on the service kit purchased. 
Based on these figures, the cost impact of the optional terminating 
modification proposed by this AD on U.S. operators is estimated to be 
as low as $1,580, or $316 per airplane and as high as $1,665, or $333 
per airplane.

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 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-194-AD.

    Applicability: Model A320 series airplanes, on which Airbus 
Modification 20941 (reference Airbus Service Bulletin A320-53-1011, 
dated December 9, 1994) has not been accomplished, 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 detect and correct fatigue cracking on the connecting angle 
between frame 56 and the right-hand frame support at stringer 38, 
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 1,000 flight cycles after the effective date of this AD, 
whichever occurs later, perform a visual inspection for fatigue 
cracking on the connecting angle between frame 56 and the right-hand 
frame support at stringer 38, in accordance with Airbus Service 
Bulletin A320-53-1084, Revision 1, dated November 28, 1995.
    (1) If no cracking is detected, accomplish either paragraph 
(a)(1)(i) or (a)(1)(ii) of this AD.
    (i) Prior to further flight, replace the connecting angle 
between frame 56 and the right-hand frame support at stringer 38 
with a new part, in accordance with Airbus Service Bulletin A320-53-
1011, dated December 9, 1994; or
    (ii) Repeat the visual inspection thereafter at intervals not to 
exceed 12,000 flight cycles.
    (2) If any cracking is detected, prior to further flight, 
replace the connecting angle between frame 56 and the right-hand 
frame support at stringer 38 with a new part, in accordance with 
Airbus Service Bulletin A320-53-1011, dated December 9, 1994.
    (b) Accomplishment of the replacement of the connecting angle 
constitutes terminating action for the repetitive inspection 
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 96-237-090(B), dated October 23, 1996, and 
Erratum to French airworthiness directive 96-237-090(B), dated 
February 26, 1997.

    Issued in Renton, Washington, on April 7, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-9759 Filed 4-13-98; 8:45 am]
BILLING CODE 4910-13-U