[Federal Register Volume 60, Number 86 (Thursday, May 4, 1995)]
[Proposed Rules]
[Pages 22011-22013]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-10988]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-NM-04-AD]
Airworthiness Directives; Airbus Model A300 and 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 all Airbus Model A300 and A300-600
series airplanes. This proposal would require repetitive eddy current
inspections to detect cracks at the aft spar web of the wings, and
repair, if necessary. This proposal is prompted by reports indicating
that cracks have been found in the rear spar web of the wings between
ribs 1 and 2 of an in-service airplane and during testing on the
fatigue test wing; the cracking occurred due to fatigue-related high
shear stress. The actions specified by the proposed AD are intended to
prevent such fatigue-related cracking, which could result in reduced
structural integrity of the wing.
DATES: Comments must be received by June 13, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-04-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: Stephen Slotte, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2797; fax (206) 227-1320.
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 95-NM-04-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-04-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 all Airbus Model A300 and A300-600 series
airplanes. The DGAC advises that cracks have been found in the rear
spar web of the wings between ribs 1 and 2 of an in-service airplane
and during testing of the fatigue test wing. In both cases, the cracks
spanned across the tip of the build slot and to the nearest adjacent
fastener hole. Investigation revealed that such cracking was caused by
fatigue-related high shear stress experienced during the landing cycle.
Further investigation revealed that the earliest damage to an in-
service airplane was found on a Model A300-B2 series airplane that had
accumulated 21,500 flight cycles. The crack in the fatigue test wing
was discovered at 50,000 simulated flight cycles, and, subsequently,
was monitored for an additional 12,000 flight cycles with no evidence
of continued crack growth from the hole. Such fatigue-related cracking,
if not detected and corrected in a timely manner, could result in
reduced structural integrity of the wing.
Airbus has issued Service Bulletin A300-57-0213, dated August 12,
1994, which is applicable to Model A300 series airplanes. This service
bulletin describes procedures for repetitive high frequency eddy
current (HFEC) inspections to detect cracks at the aft spar web of the
wings, and repair, if necesaary. The DGAC classified this service
bulletin as manadatory and issued French airworthiness directive 94-
207-168(B), dated September 14, 1994, in order to assure the continued
airworthiness of these airplanes in France.
Airbus also has issued Service Bulletin A300-57-6059, dated August
12, 1994, which is applicable to Model A300-600 series airplanes. This
service bulletin describes procedures for repetitive high frequency
eddy current (HFEC) inspections to detect cracks at the aft spar web of
the wings, and repair, if necesaary. The DGAC plans to make this
service bulletin mandatory when the Model A300-600 series airplane
fleet leader approaches the accumulation of 21,600 total flight cycles,
which is the recommended time for accomplishment of the initial
inspection.
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 [[Page 22012]] develop on other airplanes of the same type
design registered in the United States, the proposed AD would require
repetitive eddy current inspections to detect cracks at the aft spar
web of the wings, and repair, if necessary. The actions would be
required to be accomplished in accordance with the service bulletins
described previously.
Operators should note the following differences between the
procedures specified in the referenced Airbus service bulletins and the
proposed requirements of this AD:
1. Airbus Service Bulletin A300-57-0213, paragraph 1.B.(5)(c),
Accomplishment Timescale, makes allowances for airplanes that are close
to or have exceeded the specified inspection threshold to fly an
additional 1,000 or 1,800 flight cyles prior to the initial inspection,
depending upon the number of flight cycles accumulated at the time that
the operator received the service bulletin. This proposed AD, however,
would allow those airplanes to fly additional 1,400 flight cycles after
the effective date of this AD. The FAA considers that this number of
flight cycles is a reasonable number for all affected airplanes,
regardless of when the service bulletin was received.
2. Airbus Service Bulletin A300-57-0213, paragraph 1.B.(5)(d),
Accomplishment Timescale; and Airbus Service Bulletin A300-57-6059,
paragraph 1.B.(5)(c), Accomplishment Timescale; provide for adjustments
of the inspection threshold and intervals specified in the service
bulletin, under certain criteria related to the number and types of
touch-and-go flights that have been accumulated on the airplane. The
FAA considers that this criteria for adjustments may cause undue
confusion among affected operators in attempting to calculate and/or
record allowable or ``non-allowable'' types of touch-and-go flights
and, therefore, has not included those provisions of the service
bulletin in this proposed rule.
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may misunderstand the legal effect of AD's on airplanes
that are identified in the applicability provision of the AD, but that
have been altered or repaired in the area addressed by the AD. The FAA
points out that all airplanes identified in the applicability provision
of an AD are legally subject to the AD. If an airplane has been altered
or repaired in the affected area in such a way as to affect compliance
with the AD, the owner or operator is required to obtain FAA approval
for an alternative method of compliance with the AD, in accordance with
the paragraph of each AD that provides for such approvals. A note has
been included in this notice to clarify this requirement.
The FAA estimates that 89 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 3 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
total cost impact of the proposed AD on U.S. operators is estimated to
be $16,020, or $180 per airplane.
The total 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:
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 Industrie: Docket 95-NM-04-AD.
Applicability: All Model A300 and Model A300-600 series
airplanes, 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) 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, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent fatigue-related cracking in the rear spar web of the
wings, which could result in reduced structural integrity of the
wing, accomplish the following:
(a) For Model A300 B2 series airplanes: Prior to the
accumulation of 18,000 total flight cycles or within 1,400 flight
cycles after the effective date of this AD, whichever occurs later,
perform a high frequency eddy current (HFEC) inspection to detect
cracks of at the aft spar web of the wings, in accordance with
Airbus Service Bulletin A300-57-0213, dated August 12, 1994. Repeat
the inspection thereafter at intervals not to exceed 5,000 flight
cycles.
(b) For Model A300 B4-103, and B4-2C series airplanes: Prior to
the accumulation of 19,000 total flight cycles or within 1,400
flight cycles after the effective date of this AD, whichever occurs
later, perform an HFEC inspection to detect cracks at the aft spar
web of the wings, in accordance with Airbus Service Bulletin A300-
57-0213, dated August 12, 1994. Repeat the inspection thereafter at
intervals not to exceed 6,000 flight cycles.
(c) For Model A300 B4-200 series airplanes: Prior to the
accumulation of 17,000 total flight cycles or within 1,400 flight
cycles after the effective date of this AD, whichever occurs later,
perform an HFEC inspection to detect cracks at the aft spar web of
the wings, in accordance with Airbus Service Bulletin A300-57-0213,
dated August 12, 1994. Repeat the inspection thereafter at intervals
not to exceed 5,000 flight cycles.
(d) For Model A300-600 B4-601, B4-603, B4-620, B4-622, B4-605R,
B4-622R, and F4-605R series airplanes: Prior to the
[[Page 22013]] accumulation of 21,600 flight cycles, perform an HFEC
inspection to detect cracks at the aft spar web of the wings, in
accordance with Airbus Service Bulletin A300-57-6059, dated August
12, 1994. Repeat the inspection thereafter at intervals not to
exceed 5,700 flight cycles.
(e) If any crack is detected during any inspection required by
this AD, prior to further flight, repair the crack in accordance
with Airbus Service Bulletin A300-57-0213, dated August 12, 1994, or
Airbus Service Bulletin A300-57-6059, dated August 12, 1994, as
applicable; or in accordance with a method approved by the Manager,
Standardization Branch, ANM-113, FAA, Transport Airplane
Directorate.
(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,
FAA, Transport Airplane Directorate. 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 April 28, 1995.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-10988 Filed 5-3-95; 8:45 am]
BILLING CODE 4910-13-U
