[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
