[Federal Register Volume 63, Number 178 (Tuesday, September 15, 1998)]
[Rules and Regulations]
[Pages 49272-49273]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-24248]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-156-AD; Amdt. 39-10740; AD 98-18-24]
RIN 2120-AA64


Airworthiness Directives; Airbus Industrie Model A320 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 certain Airbus Model A320 series airplanes, that requires 
repetitive inspections to detect cracking in the inner flange of door 
frame 66, and corrective actions, if necessary. This amendment also 
provides for an optional terminating action for the repetitive 
inspections. This amendment is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified by this AD are intended to correct 
fatigue cracking in the inner flange of door frame 66, which could 
result in reduced structural integrity of the airplane.

DATES: Effective October 20, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 20, 1998.

ADDRESSES: The service information referenced in this AD may be 
obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. 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: 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: 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 certain Airbus Model A320 series 
airplanes was published in the Federal Register on May 12, 1998 (63 FR 
26102). That action proposed to require repetitive inspections to 
detect cracking in the inner flange of door frame 66, and corrective 
actions, if necessary. That action also proposed to provide for an 
optional terminating action for the repetitive inspections.
    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 intent of the proposed rule.

Request To Allow Flight With Known Cracks

    One commenter, the manufacturer, requests that the proposed AD be 
revised to allow operators to continue operation of an unrepaired 
airplane following detection of cracks, utilizing the follow-on 
inspections and conditions described in Airbus Service Bulletin A320-
53-1071. The commenter states that the follow-on inspection intervals 
are based on fatigue test results and calculations of the crack 
propagation rate, depending on the crack length. The commenter also 
states that the structure of the Airbus Model A320 series airplane is 
classified as damage tolerant. Additionally, the commenter notes that 
the inspection program specified in the service bulletin was developed 
in order to prevent the need for extensive repairs of the airplane.
    The FAA does not concur. It is the FAA's policy to require repair 
of known cracks prior to further flight, except in certain cases of 
unusual need, as discussed below.
    This policy is based on the fact that such damaged airplanes do not 
conform to the FAA certificated type design, and therefore, are not 
airworthy until a properly approved repair is incorporated. While 
recognizing that repair deferrals may be necessary at times, the FAA 
policy is intended to minimize adverse human factors relating to the 
lack of reliability of long-term repetitive inspections, which may 
reduce the safety of the type certificated design if such repair 
deferrals are practiced routinely.
    As noted above, the FAA's policy regarding flight with known cracks 
does allow deferral of repairs in certain cases, if there is an unusual 
need for a temporary deferral. Unusual needs include such circumstances 
as legitimate difficulty in acquiring parts to accomplish repairs. 
Under such conditions, the FAA may allow a temporary deferral of the 
repair, subject to a stringent inspection program acceptable to the 
FAA. The FAA acknowledges that the manufacturer has specified 
inspection intervals that are intended to allow continued operation 
with known cracks, and to prevent the need for extensive repairs. 
However, since the FAA is not aware of any unusual need for repair 
deferral in regard to this AD, the FAA has not evaluated these 
inspection intervals.
    Additionally, the FAA policy applies to airplanes certificated to 
damage tolerance evaluation regulations as well as those not so 
certificated. Therefore, the commenter's statement that ``the Airbus 
Model A320 airplane structure is classified as damage tolerant'' is not 
relevant to the application of the FAA's policy in this regard.
    The FAA considers the compliance times in this AD to be adequate to 
allow operators to acquire parts to have on hand in the event that a 
crack is detected during inspection. Therefore, the FAA has determined 
that, due to the safety implications and consequences associated with 
such cracking, any subject area that is found to be cracked must be 
repaired or modified prior to further flight. No change to the final 
rule is necessary.

Conclusion

    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 as proposed.

Cost Impact

    The FAA estimates that 132 Airbus Model A320 series airplanes of 
U.S. registry will be affected by this AD, that it will take 
approximately 8 work hours per airplane to accomplish the required 
inspection, and that the average labor rate is $60 per work hour. Based 
on these figures, the cost impact of the inspection required by this AD 
on U.S. operators is estimated to be $63,360, or $480 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the requirements of this AD 
action, and

[[Page 49273]]

that no operator would accomplish those actions in the future if this 
AD were not adopted.
    Should an operator elect to accomplish the modification, it would 
take approximately 5 work hours per airplane to accomplish the actions, 
at an average labor rate of $60 per work hour. Based on these figures, 
the cost impact of the optional modification provided by this AD on 
U.S. operators is estimated to be $300 per airplane.

Regulatory Impact

    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 U.S.C. 106(g), 40113, 44701.

Sec. 39.13  [Amended]

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

98-18-24 Airbus Industrie: Amendment 39-10740. Docket 97-NM-156-AD.

    Applicability: Model A320 series airplanes on which Airbus 
Modification 21778 (reference Airbus Service Bulletin A320-53-1072, 
dated November 7, 1995, as revised by Change Notice 0A, dated July 
5, 1996) 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 correct fatigue cracking in the inner flange of door frame 
66, left and right, 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 year after the effective date of this AD, whichever occurs 
later: Perform a rotating probe eddy current inspection to detect 
cracking around the edges of the gusset plate attachment holes of 
the inner flange of door frame 66, left and right, at stringer 
positions P18, P20, P22, P18, P20, and P22, in accordance with 
Airbus Service Bulletin A320-53-1071, dated November 7, 1995, as 
revised by Change Notice 0A, dated July 5, 1996. If any crack is 
detected, prior to further flight, repair in accordance with a 
method approved by the Manager, International Branch, ANM-116, FAA, 
Transport Airplane Directorate. Repeat the inspection thereafter at 
intervals not to exceed 20,000 flight cycles.
    (b) Modification of the gusset plate attachment holes of the 
inner flange of door frame 66, left and right (Airbus Modification 
21778), in accordance with Airbus Service Bulletin A320-53-1072, 
dated November 7, 1995, as revised by Change Notice 0A, dated July 
5, 1996, 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. 
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 
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.
    (e) The inspections shall be done in accordance with Airbus 
Service Bulletin A320-53-1071, dated November 7, 1995, as revised by 
Change Notice 0A, dated July 5, 1996. 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 Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. 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.

    Note 3: The subject of this AD is addressed in French 
airworthiness directive 96-234-087(B), dated October 20, 1996.

    (f) This amendment becomes effective on October 20, 1998.

    Issued in Renton, Washington, on August 28, 1998.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-24248 Filed 9-14-98; 8:45 am]
BILLING CODE 4910-13-U