[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