[Federal Register Volume 60, Number 238 (Tuesday, December 12, 1995)]
[Proposed Rules]
[Pages 63665-63667]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-30212]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-78-AD]
Airworthiness Directives; Airbus Model A300-600 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 A300-600
series airplanes. This proposal would require inspections to detect
corrosion and cracking of the lower horizontal-stabilizer cutout
longeron, the corner fitting, the skin strap, and the outer skin; and
repair, if necessary. This proposal is prompted by cracking found at
the lower corner of the horizontal-stabilizer cutout longeron during a
full scale fatigue test. The actions specified by the proposed AD are
intended to prevent such cracking, which could result in reduced
structural integrity of the horizontal stabilizer cutout longeron.
DATES: Comments must be received by January 23, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-78-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: Charles Huber, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
277-2589; fax (206) 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. 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
[[Page 63666]]
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 95-NM-78-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-103, Attention: Rules
Docket No. 95-NM-78-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 A300-600 series
airplanes. The DGAC advises that, during a full-scale fatigue test,
cracking was found on the test airplane at the lower corner of the
horizontal-stabilizer cutout longeron, between frame (FR) 87 and FR89
and between stringer (STGR) 24 and STGR27, left- and right-hand. The
cracking was found after 87,675 simulated flights. Such fatigue
cracking, if not corrected, could result in reduced structural
integrity of the horizontal stablizer cutout longeron.
Airbus has issued Service Bulletin A300-53-6042, Revision 1, dated
February 20, 1995, which describes procedures for repetitive visual and
eddy current inspections to detect corrosion and cracking of the lower
horizontal-stabilizer cutout longeron, the corner fitting, the skin
strap, and the outer skin between FR87 and FR89 and between STGR24 and
STGR27, left- and right-hand; and repair, if necessary. The service
bulletin also describes procedures for repetitive rotating probe
inspections to detect cracks in the fastener holes at the same
locations, and repair, if necessary. The service bulletin also
describes procedures for certain follow-on actions, which include
installing a new corner fitting, installing a new longeron, and
performing a cold working procedure repairing cracks of certain
measurements. The DGAC classified this service bulletin as mandatory
and issued French airworthiness directive (CN) 94-269-171(B)R1, dated
March 29, 1995, in order to assure the continued airworthiness of these
airplanes in France.
This airplane model is manufactured in France and is type
certificated for operation in the United States under the provisions of
section 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.
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 repetitive visual
and eddy current inspections to detect corrosion and fatigue cracking
of the lower horizontal-stabilizer cutout longeron, the corner fitting,
the skin strap, and the skin between FR87 and FR89 and between STGR24
and STGR27, left-hand and right-hand. The proposed AD would also
require repetitive rotating probe inspections to detect cracks in the
fastener holes at the same locations; and repair or certain a follow-on
actions, if necessary. The actions would be required to be accomplished
in accordance with the service bulletin described previously. Certain
repairs would be required to be accomplished in accordance with a
method approved by the FAA.
Operators should note that certain requirements of this proposed AD
would differ from actions recommended in the referenced Airbus service
bulletin. The service bulletin specifies that inspection thresholds and
intervals may be adjusted based on certain average flight operations of
the airplane. However, the FAA has determined that such adjustments
would not address the unsafe condition in a timely manner. Therefore,
this proposed AD does not permit such adjustments. In developing the
appropriate compliance time for the proposed rule, the FAA considered
not only the manufacturer's recommendation, but the safety implications
involved with cracking of the horizontal-stabilizer cutout longeron and
the number of landings that had been accumulated when cracking was
detected. In light of these factors, the FAA finds the compliance times
specified in the proposed AD for initiating the required actions to be
warranted, in that they represent an appropriate interval of time
allowable for the affected airplanes to continue to operate without
compromising safety.
Additionally, the service bulletin specifies that operators need
not count touch-and-go landings in determining the total number of
landings between two consecutive inspections, even if those landings
are less than five percent of the landings between inspection
intervals. Since the fatigue cracking that was found in the lower
horizontal stabilizer cutout longeron is aggravated by landing, the FAA
finds that all touch-and-go landings must be counted in determining the
total number of landings between two consecutive inspections.
The FAA estimates that 2 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 268 work
hours per airplane to accomplish the proposed actions, 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
$32,160 to $16,080 per airplane.
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.
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:
[[Page 63667]]
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Airbus Industries: Docket 95-NM-78-AD.
Applicability: Model A300-600 series airplanes on which Airbus
Modification No. 6146 has not 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
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 use the authority
provided in paragraph (f) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in this AD. Such
a request should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alternation, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent reduced structural integrity of the horizontal
stabilizer cutout longeron due to fatigue cracking, accomplish the
following:
(a) Prior to the accumulation of 18,000 total landings, or
within 2,000 landings after the effective date of this AD, whichever
occurs later: Perform a visual and an eddy current inspection to
detect cracks and/or corrosion of Areas 1 and 2 of the lower
horizontal stabilizer cutout longeron, as defined in Airbus Service
Bulletin A300-53-6042, Revision 1, and dated February 20, 1995.
Perform the inspections in accordance with the service bulletin.
(b) Perform a visual and an eddy current inspection to detect
cracks and/or corrosion of Area 3 of the lower horizontal-stabilizer
cutout longeron, as defined in Airbus Service Bulletin A300-53-6042,
Revision 1, dated February 20, 1995. Perform these inspections in
accordance with the service bulletin, at the later of the times
specified in paragraph (b)(1) and (b)(2) of this AD.
(1) Prior to the accumulation of 24,000 total landings, but not
before the accumulation of 18,000 total landings; or
(2) Prior to the accumulation of 2,000 landings after the
effective date of this AD.
(c) If no cracking is detected during any inspection required by
this AD: Prior to further flight, cold work and ream the vacated
fastener holes, in accordance with Airbus Service Bulletin A300-53-
6042, Revision 1, dated February 20, 1995; and perform the
requirements of paragraph (c)(1) or (c)(2) of this AD, as
applicable.
(1) For airplanes on which no cracking is found in Area 1 or 2:
Repeat the inspections required by paragraph (a) of this AD
thereafter at intervals not to exceed 6,000 flight cycles.
(2) For airplanes on which no cracking is found in Area 3:
Perform the various follow-on actions in accordance with the service
bulletin. (The follow-on actions include installing a new corner
fitting, installing a new longeron and performing a cold working
procedure.) After accomplishment of these follow-on actions, no
further action is required by this AD.
(d) If any cracking is detected during any inspection required
by this AD, perform the requirements of paragraph (d)(1) or (d)(2)
of this AD, as applicable.
(1) If any cracking is found in Area 1 or 3 that is within the
limits specified in Airbus Service bulletin A300-53-6042, Revision
1, dated February 20, 1995: Prior to further flight, repair in
accordance with the service bulletin.
(2) If any cracking is found in Area 2, or if any cracking is
found in any area and that cracking is beyond the limits described
in Airbus Service Bulletin A300-53-6042, Revision 1, dated February
20, 1995: Prior to further fight, repair in accordance with a method
approved by the Manager, Standardization Branch, ANM-113, FAA,
Transport Airplane Directorate.
(e) If any corrosion is detected during any inspection required
by this AD, prior to further flight, repair the corrosion in
accordance with Airbus Service Bulletin A300-53-6042, Revision 1,
dated February 20, 1995.
(f) 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, Standardization Branch, ANM-113.
Operators shall submit their requests through an appropriate FAA
Principal Maintenance Inspector, who may add comments and then send
it to the Manager, Standardization Branch, ANM-113.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(g) 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.
Issued in Renton, Washington, on December 6, 1995.
Darrell M. Pederson,
Acting Manger, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-30212 Filed 12-11-95; 8:45 am]
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