[Federal Register Volume 63, Number 80 (Monday, April 27, 1998)]
[Proposed Rules]
[Pages 20546-20548]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-11090]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-77-AD]
RIN 2120-AA64
Airworthiness Directives; Airbus Model A320 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
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
cracking in the pressurized floor pick-up angles on the rear spar of
the wing, and replacement of any cracked pick-up angle and its
associated diaphragms with improved parts. Such replacement would
terminate the repetitive inspections for that angle. 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 cracking in the
pressurized floor pick-up angles at the rear spar of the wing, which
could result in reduced structural integrity of the airframe.
DATES: Comments must be received by May 27, 1998.
[[Page 20547]]
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 98-NM-77-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 98-NM-77-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. 98-NM-77-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 or develop on certain Airbus Model A320 series
airplanes. The DGAC advises that, during fatigue testing, cracking was
found on a test article in the pressurized floor pick-up angles at the
rear spar of the wing. Such fatigue cracking, if not detected and
corrected in a timely manner, could result in reduced structural
integrity of the airframe.
Explanation of Relevant Service Information
The manufacturer has issued Airbus Service Bulletin A320-57-1090,
Revision 01, dated June 10, 1997, which describes procedures for
repetitive eddy current inspections to detect cracking in the
pressurized floor pick-up angles on the rear spar of the wing. The
manufacturer also has issued Airbus Service Bulletin A320-57-1025,
Revision 05, dated June 26, 1997, which describes procedures for
replacing any cracked pick-up angle and its associated diaphragms with
improved parts. Accomplishment of the replacement involves removing
existing fasteners, diaphragms, and pick-up angles; installing improved
pick-up angles, diaphragms, and fasteners; cold expanding certain
fastener holes; and performing a rotating probe inspection for cracking
of the fastener holes. Such replacement would eliminate the need for
the repetitive inspection requirement for that pick-up angle.
Accomplishment of the replacement is intended to adequately address the
identified unsafe condition.
The DGAC classified Airbus Service Bulletin A320-57-1090 as
mandatory and issued French airworthiness directive CN 97-084-097 (B),
dated March 12, 1997, in order to assure the 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
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 inspections specified in Airbus Service Bulletin A320-57-1090,
Revision 01, 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 cracking before it represents a hazard to the airplane.
Differences Between Proposed Rule and Service Bulletin
Operators should note that, unlike the procedures described in
Airbus Service Bulletin A320-57-1090, this proposed AD would not permit
further flight if cracks are detected in any pressurized floor pick-up
angle. The FAA has determined that, because of the safety implications
and consequences associated with such cracking, any subject pressurized
floor pick-up angle that is found to be cracked must be replaced prior
to further flight.
Operators also should note that, although Airbus Service Bulletin
A320-57-1025 specifies that the manufacturer may be contacted for
disposition of certain repair conditions associated with accomplishment
of the replacement, this proposal would require the repair of those
conditions to 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 would be acceptable for
compliance with this proposed AD.
[[Page 20548]]
Cost Impact
The FAA estimates that 120 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 8 work
hours per airplane (including access and close) 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 $57,600, or $480 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 that would be provided by this proposed AD action, it would take
approximately 140 work hours to accomplish, at an average labor rate of
$60 per work hour. The cost of required parts would be approximately
$10,103 per airplane. Based on these figures, the cost impact of that
optional terminating action would be $18,503 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 98-NM-77-AD.
Applicability: Model A320 series airplanes, as listed in Airbus
Service Bulletin A320-57-1090, Revision 01, dated June 10, 1997;
certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
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 (d) 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 cracking in the pressurized floor pick-up
angles at the rear spar of the wing, which could result in reduced
structural integrity of the airframe, accomplish the following:
(a) Prior to the accumulation of 20,000 total flight cycles, or
within 60 days after the effective date of this AD, whichever occurs
later: Perform an eddy current inspection to detect cracking in the
pressurized floor pick-up angles on the rear spar of the wing, in
accordance with Airbus Service Bulletin A320-57-1090, Revision 01,
dated June 10, 1997.
(1) If no cracking is found, repeat the inspection thereafter at
intervals not to exceed 10,000 flight cycles.
(2) If any cracking is found during any inspection required by
this AD, prior to further flight, replace each cracked pick-up angle
and its associated diaphragms with improved parts, in accordance
with Airbus Service Bulletin A320-57-1025, Revision 05, dated June
26, 1997. For all pick-up angles not replaced with improved angles,
repeat the inspection thereafter at intervals not to exceed 10,000
flight cycles.
(b) Replacement of a pick-up angle and its associated diaphragms
with improved parts, in accordance with Airbus Service Bulletin
A320-57-1025, Revision 05, dated June 26, 1997, constitutes
terminating action for the repetitive inspection requirements for
that pick-up angle.
(c) If any crack is detected during any inspection required by
this AD, and the applicable service bulletin specifies to contact
Airbus for appropriate action: 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 (or its delegated
agent).
(d) 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 request 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.
(e) 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 3: The subject of this AD is addressed in French
airworthiness directive CN 97-084-097 (B), dated March 12, 1997.
Issued in Renton, Washington, on April 21, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-11090 Filed 4-24-98; 8:45 am]
BILLING CODE 4910-13-U