[Federal Register Volume 64, Number 141 (Friday, July 23, 1999)]
[Proposed Rules]
[Pages 39946-39949]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-18861]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-91-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A310 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 A310 series 
airplanes. This proposal would require repetitive high frequency eddy 
current inspections to detect fatigue cracking at the hole in the lower 
web of the inner and outer attachment fittings of the number 3 wing 
spoilers; and corrective actions, if necessary. This proposal also 
provides for an optional modification, 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 detect and correct fatigue cracking and eventual failure of 
the attachment fittings of the number 3 wing spoilers.

DATES: Comments must be received by August 23, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-91-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:

[[Page 39947]]

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-91-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-91-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, recently notified the FAA that an 
unsafe condition may exist on certain Airbus Model A310 series 
airplanes. The DGAC advises that it has received reports of fatigue 
cracking in the attachment fittings of the number 3 wing spoilers. The 
propagation of such cracks could result in the deformation of the wing 
rear spar web and associated Titanium doubler which, if left 
undetected, could lead to fuel leaks and loss of various hydraulic and 
electrical systems.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A310-57-2078, Revision 01, dated 
January 11, 1999, which describes procedures for repetitive high 
frequency eddy current inspections to detect fatigue cracking at the 
hole in the lower web of the inner and outer attachment fittings of the 
number 3 wing spoilers, and corrective actions, if necessary. (The 
corrective actions are contained in the service bulletin described 
below.) The DGAC classified this service bulletin as mandatory and 
issued French airworthiness directive 98-483-271(B) R1, dated June 2, 
1999, in order to assure the continued airworthiness of these airplanes 
in France.
    Airbus also has issued Service Bulletin A310-75-2079, Revision 01, 
dated January 11, 1999, which describes procedures for performing a 
high frequency eddy current inspection to detect fatigue cracking of 
holes in the wing structure; reaming and cold working of those holes; 
and replacing the attachment fittings with new steel fittings.
    Accomplishment of this replacement would eliminate the need for the 
repetitive inspections described in Airbus Service Bulletin A310-57-
2078.
    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition.

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. Additionally, the FAA has determined that, for 
certain instances where cracking is detected, the repair may be 
deferred for a specified period of time. In making these 
determinations, the FAA considers that, in the case of this AD, long-
term continued operational safety will be adequately assured by 
accomplishing the repetitive inspections to detect cracking before it 
represents a hazard to the airplane, and by accomplishing repairs 
within the specified time limits.

Differences Between the Proposed AD and Service Bulletins

    The referenced service bulletins do not include any repair 
procedures for cracks found in the holes of the wing structure that is 
not part of the attachment fittings. This proposal would require that 
repair of such cracks 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 (or its 
delegated agent) would be acceptable for compliance with this proposed 
AD.

Cost Impact

    The FAA estimates that 44 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 2 work 
hours per airplane to accomplish the proposed inspection, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$5,280, or $120 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 accomplish the optional terminating 
action rather than continue the repetitive inspections, it would take 
approximately 110 work hours per airplane to accomplish the 
modification, at an average labor rate of $60 per work hour.
    Required parts will cost approximately $13,280 per airplane. Based 
on these figures, the cost impact of this optional terminating action 
is estimated to be $19,880 per airplane.

[[Page 39948]]

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 99-NM-91-AD.

    Applicability: Model A310 series airplanes, on which Airbus 
Industrie Modification 04117 or 04799 has been installed in 
production; except those airplanes on which Airbus Industrie 
Modification 11929 (reference Airbus Industrie Service Bulletin 
A310-57-2079, dated July 21, 1998, or Revision 01, dated January 11, 
1999) has been installed; 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 (e) 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 and eventual failure of 
the attachment fittings of the number 3 wing spoilers, which, if 
left undetected, could lead to fuel leaks and loss of various 
hydraulic and electrical systems, accomplish the following:

Inspection

    (a) At the applicable compliance time specified in paragraph 
(a)(1), (a)(2), or (a)(3) of this AD, perform a high frequency eddy 
current inspection to detect fatigue cracking at the hole in the 
lower web of the inner and outer attachment fittings of the number 3 
wing spoilers, in accordance with Airbus Industrie Service Bulletin 
A310-57-2078, Revision 01, dated January 11, 1999. Repeat the 
inspection thereafter at intervals not to exceed 1,200 flight 
cycles.
    (1) For airplanes that have accumulated 14,200 or fewer total 
flight cycles as of the effective date of this AD, accomplish the 
inspection required by paragraph (a) of this AD prior to the 
accumulation 10,800 total flight cycles or within 800 flight cycles 
after the effective date of this AD, whichever occurs later.
    (2) For airplanes that have accumulated more than 14,200 total 
flight cycles but fewer than 15,400 total flight cycles as of the 
effective date of this AD, accomplish the inspection required by 
paragraph (a) of this AD within 400 flight cycles after the 
effective date of this AD.
    (3) For airplanes that have accumulated 15,400 or more total 
flight cycles as of the effective date of this AD, accomplish the 
inspection required by paragraph (a) of this AD within 200 flight 
cycles after the effective date of this AD.

    Note 2: Inspection of the attachment fittings of the number 3 
wing spoilers accomplished prior to the effective date of this AD in 
accordance with the original issue of Airbus Industrie Service 
Bulletin A310-57-2078, dated July 21, 1998, is considered acceptable 
for compliance with the inspection required by paragraph (a) of this 
AD.

Replacement

    (b) If any crack is found during any inspection required by 
paragraph (a) of this AD, at the applicable compliance time 
specified in paragraph (b)(1), (b)(2), or (b)(3) of this AD, perform 
a high frequency eddy current inspection for fatigue cracking of the 
holes in the wing structure; ream and cold work those holes; and 
replace the cracked aluminum wing spoiler number 3 actuator 
attachment fitting with a new steel fitting; in accordance with 
Airbus Industrie Service Bulletin A310-57-2079, Revision 01, dated 
January 11, 1999. Accomplishment of the replacement constitutes 
terminating action for the repetitive inspection requirements of 
paragraph (a) of this AD for the replaced fitting.
    (1) If the crack is less than 0.078 inches (2.0 mm) in length, 
inspect, ream, cold work, and replace within 100 flight cycles after 
accomplishment of the inspection.
    (2) If the crack is 0.078 inches (2.0 mm) in length or greater 
and less than 0.118 inches (5.0 mm) in length, inspect, ream, cold 
work, and replace within 50 flight cycles after accomplishment of 
the inspection.
    (3) If the crack is greater than 0.118 inches (5.0 mm) in 
length, inspect, ream, cold work, and replace prior to further 
flight.

Optional Terminating Modification

    (c) Accomplishment of the high frequency eddy current inspection 
for fatigue cracking of the holes in the wing structure; reaming and 
cold working of those holes; and replacement of all aluminum wing 
spoiler number 3 actuator attachment fittings with new steel 
fittings; in accordance with Airbus Industrie Service Bulletin A310-
57-2079, Revision 01, dated January 11, 1999; constitutes 
terminating action for the repetitive inspection requirements of 
paragraph (a) of this AD.

    Note 3: Replacement of aluminum attachment fittings of the 
number 3 wing spoilers with steel fittings accomplished prior to the 
effective date of this AD in accordance with the original issue of 
Airbus Industrie Service Bulletin A310-57-2079, dated July 21, 1998, 
is considered acceptable for compliance with the applicable fitting 
replacement specified in paragraphs (b) and (c) of this AD.

Wing Repair

    (d) If any crack is found in the wing structure during any 
inspection required by paragraph (b) or specified in paragraph (c) 
of this AD, prior to further flight, repair in accordance with a 
method approved by either 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.

    Note 4: For paragraph (d) of this AD, the wing spoiler number 3 
actuator attachment fittings are not considered part of the wing 
structure.

Alternative Methods of Compliance

    (e) 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 5: Information concerning the existence of approved 
alternative methods of

[[Page 39949]]

compliance with this AD, if any, may be obtained from the 
International Branch, ANM-116.

Special Flight Permits

    (f) 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 6: The subject of this AD is addressed in French 
airworthiness directive 98-483-271(B) R1, dated June 2, 1999.

    Issued in Renton, Washington, on July 19, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-18861 Filed 7-22-99; 8:45 am]
BILLING CODE 4910-13-P