[Federal Register Volume 60, Number 195 (Tuesday, October 10, 1995)]
[Rules and Regulations]
[Pages 52618-52620]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-23812]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-56-AD; Amendment 39-9380; AD 95-20-02]


Airworthiness Directives; Airbus Model A300-600 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Airbus Model A300-600 series airplanes, that 
requires inspections to detect cracks in bolt holes where parts of the 
main landing gear (MLG) are attached to the rear spar, and repair, if 
necessary. This amendment is prompted by a report that cracks emanating 
from bolt holes in the rear spar were found during full-scale fatigue 
testing. The actions specified by this AD are intended to prevent 
unnecessary degradation of the structural integrity of the airframe due 
to cracks in the rear spar.

DATES: Effective November 9, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 9, 1995.

ADDRESSES: The service information referenced in this AD may be 
obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. This information may be examined at the Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 1601 Lind Avenue SW., Renton, Washington; or at the Office of 
the Federal Register, 800 North Capitol Street NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT:
Phil Forde, Aerospace Engineer, Standardization Branch, ANM-113, FAA, 
Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, 
Washington 98055-4056; telephone (206) 227-2146; fax (206) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Airbus Model A300-600 
series airplanes was published in the Federal Register on July 12, 1994 
(59 FR 35488). That action proposed to require repetitive high 
frequency eddy current (HFEC) rototest inspections to detect cracks in 
certain bolt holes where the main landing gear (MLG) forward pick-up 
fitting and the MLG rib 5 aft are attached to the rear spar, and 
repair, if necessary.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter supports the proposed rule.
    Another commenter, the Air Transport Association (ATA) of America 
on behalf of one of its members, requests that the proposed repetitive 
inspection intervals be revised, since they are more stringent 
(shorter) for airplanes on which Modification 07716 has been 
accomplished. ATA advises that it has contacted the manufacturer to ask 
that the repetitive inspections specified in Airbus Service Bulletin 
A300-57-6017, dated November 22, 1993 (which is referenced in the 
proposal as the appropriate source of service information), be reviewed 
and changed if correction is necessary. ATA requests that the FAA 
revise the final rule to incorporate such changes that the manufacturer 
may be considering.
    The FAA does not concur that the repetitive inspection requirements 
need to be changed. The Direction Generale de l'Aviation Civile (DGAC), 
which is the airworthiness authority for France, has assured the FAA 
that the repetitive intervals, although unusual, are appropriate for 
identifying the subject cracking in a timely manner. Modification 07716 
involves oversizing the bolt holes; therefore if a crack were to 
develop, it could reach critical length sooner than a crack would on an 
airplane on which that modification has not been accomplished. 
Additionally, the DGAC has advised the FAA that, although modification 
07716 provides additional fatigue life, the inspection interval as 
cited in the final rule would allow detection of further cracking 
before a crack reaches a critical length.
    However, the DGAC also has advised the FAA that the use of HFEC 
techniques to detect cracking, as specified in the proposed rule, may 
not accurately measure crack lengths as short as 1 mm (.039 inch). The 
FAA concurs with these DGAC findings. Since the issuance of that 
proposal, Airbus has issued Service Bulletin A300-57-6017, Revision 1, 
dated July 25, 1994, which describes procedures for oversizing the bolt 
holes before performing the HFEC in order to accurately detect any 
cracking. The DGAC classified this service bulletin as mandatory. The 
final rule has been changed to reference this revised service bulletin 
as the appropriate source of service information, in order to ensure 

[[Page 52619]]
that the bolt holes are oversized prior to accomplishment of the HFEC 
inspection. The FAA has determined that this minor change in inspection 
procedures will not impose an additional burden on any operator, and is 
a logical outgrowth of the notice that does not necessitate providing 
an additional opportunity for public comment.
    Paragraph (c) of the proposal required repair of cracks found in 
accordance with paragraph (a) of the proposal. Since repairs are also 
necessary for cracks found during repetitive inspections, that 
paragraph also should have required repair of cracks found in 
accordance with paragraph (b). Therefore, paragraph (c) of the final 
rule has been changed to correct this inadvertent omission by adding 
the reference to paragraph (b).
    Additionally, a note has been added to the final rule to indicate 
that accomplishment of the inspections and repair of cracking in 
accordance with Airbus Industrie Service Bulletin A300-57-6017 
(original issue), dated November 22, 1993, prior to the effective date 
of this AD, is acceptable for compliance with applicable actions 
specified in the final 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 new Note 1 
has been added to this final rule to clarify this long-standing 
requirement. (All subsequent notes in the final rule have been 
renumbered accordingly.)
    Subsequent to the issuance of the proposal, the FAA reviewed the 
figures it has used over the past several years in calculating the 
economic impact of AD activity. In order to account for various 
inflationary costs in the airline industry, the FAA has determined that 
it is necessary to increase the labor rate used in these calculations 
from $55 per work hour to $60 per work hour. The economic impact 
information, below, has been revised to reflect this increase in the 
specified hourly labor rate.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 25 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 240 work hours per 
airplane to accomplish the required actions (including time to gain 
access and close up), and that the average labor rate is $60 per work 
hour. Based on these figures, the total cost impact of the AD on U.S. 
operators is estimated to be $360,000, or $14,400 per airplane, per 
airplane cycle.
    The total cost impact figure discussed above is based on 
assumptions that no operator has yet accomplished any of the 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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 USC 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

95-20-02  Airbus Industrie: Amendment 39-9380. Docket 94-NM-56-AD.

    Applicability: Model A300-600 series airplanes; having 
manufacturer's serial numbers (MSN) 252 through 553 inclusive; and 
on which Airbus Industrie Production Modification No. 07601 has not 
been accomplished prior to delivery; 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 (d) 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, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent degradation of the structural integrity of the 
airframe due to cracks in the rear spar, accomplish the following:

    Note 2: Accomplishment of the inspections and repair of cracking 
in accordance with Airbus Industrie Service Bulletin A300-57-6017, 
dated November 22, 1993, prior to the effective date of this AD, is 
acceptable for compliance with the applicable action specified in 
this amendment.
    (a) Perform a high frequency eddy current (HFEC) rototest 
inspection to detect cracks in certain bolt holes where the main 
landing gear (MLG) forward pick-up fitting and MLG rib 5 aft are 
attached to the rear spar, in accordance with Airbus Industrie 
Service Bulletin A300-57-6017, Revision 1, (includes Appendix 1), 
dated July 25, 1994.

    Note 3: This service bulletin also references Airbus Industrie 
Service Bulletin A300-57-6020, dated November 22, 1993, as an 
additional source of service information.

    (1) For airplanes that have accumulated 17,300 total landings or 
less as of the 

[[Page 52620]]
effective date of this AD: Inspect prior to the accumulation of 17,300 
total landings, or within 1,500 landings after the effective date of 
this AD, whichever occurs later.
    (2) For airplanes that have accumulated 17,301 or more total 
landings, but less than 19,300 total landings as of the effective 
date of this AD: Inspect within 1,500 landings after the effective 
date of this AD.
    (3) For airplanes that have accumulated 19,300 or more total 
landings as of the effective date of this AD: Inspect within 750 
landings after the effective date of this AD.
    (b) If no crack is found during the inspection required by 
paragraph (a) of this AD, repeat that inspection thereafter at the 
time specified in either paragraph (b)(1) or (b)(2) of this AD, as 
applicable.
    (1) For airplanes on which Airbus Industrie Modification 07716 
(as described in Airbus Industrie Service Bulletin A300-57-6020) has 
not been accomplished, inspect at the time specified in paragraph 
(b)(1)(i) or (b)(1)(ii) of this AD, as applicable.
    (i) For airplanes having MSN 465 through 553 inclusive: Repeat 
the inspection at intervals not to exceed 13,000 landings.
    (ii) For airplanes having MSN 252 through 464 inclusive: Repeat 
the inspection at intervals not to exceed 8,400 landings.
    (2) For airplanes on which Airbus Industrie Modification 07716 
has been accomplished, inspect at the time specified in either 
paragraph (b)(2)(i) or (b)(2)(ii) of this AD, as applicable.
    (i) For airplanes having MSN 465 through 553 inclusive: Repeat 
the inspection at intervals not to exceed 11,800 landings.
    (ii) For airplanes having MSN 252 through 464 inclusive: Repeat 
the inspection within 10,700 landings following the initial 
inspection required by paragraph (a) of this AD, and thereafter at 
intervals not to exceed 7,500 landings.
    (c) If any crack is found during the inspection required by 
either paragraph (a) or (b) of this AD, prior to further flight, 
accomplish the requirements of either paragraph (c)(1) or (c)(2) of 
this AD, as applicable.
    (1) For airplanes on which Airbus Industrie Modification 07716 
has not been accomplished: Oversize the bolt hole by \1/32\ inch and 
repeat the HFEC inspection required by paragraph (a) of this AD, in 
accordance with Airbus Service Bulletin 300-57-6017, Revision 1, 
dated July 25, 1994. After accomplishing the oversizing and HFEC 
inspection, repeat the inspection as required by paragraph (b) of 
this AD at the applicable schedule specified in that paragraph.
    (i) If no cracking is detected, install the second oversize bolt 
in accordance with the service bulletin.
    (ii) If any cracking is detected, repair in accordance with a 
method approved by the Manager, Standardization Branch, ANM-113, 
FAA, Transport Airplane Directorate.
    (2) For airplanes on which Airbus Industrie Modification 07716 
has been accomplished: Repair in accordance with a method approved 
by the Manager, Standardization Branch, ANM-113. After repair, 
repeat the inspections as required by paragraph (b) of this AD at 
the applicable schedule specified in that paragraph.
    (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, 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 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (e) 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.
    (f) The inspections and installation shall be done in accordance 
with Airbus Industrie Service Bulletin A300-57-6017, Revision 1 
(includes Appendix 1), dated July 25, 1994. This incorporation by 
reference was approved by the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. Copies may be inspected at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or 
at the Office of the Federal Register, 800 North Capitol Street NW., 
suite 700, Washington, DC.
    (g) This amendment becomes effective on November 9, 1995.

    Issued in Renton, Washington, on September 20, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-23812 Filed 10-6-95; 8:45 am]
BILLING CODE 4910-13-U