AD Amdt-39-10718

[Federal Register Volume 63, Number 166 (Thursday, August 27, 1998)]
[Rules and Regulations]
[Pages 45689-45692]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 98-22818]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-NM-200-AD; Amendment 39-10718; AD 98-18-02]
RIN 2120-AA64


Airworthiness Directives; Airbus Industrie Model A300-600 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to all Airbus Industrie Model A300-600 series 
airplanes, that currently requires inspections to detect cracks in the 
center spar sealing angles adjacent to the pylon rear attachment and in 
the adjacent butt strap and skin panel, and correction of 
discrepancies. This amendment requires that the initial inspections be 
accomplished at reduced thresholds. This action also limits the 
applicability of the existing AD. This amendment is prompted by reports 
of cracking in the vertical web of the center spar sealing angles of 
the wing. The actions specified by this AD are intended to prevent 
crack formation in the sealing angles; such cracks could rupture and 
lead to subsequent crack formation in the bottom skin of the wing, and 
resultant reduced structural integrity of the center spar section of 
the wing.

DATES: Effective October 1, 1998.
    The incorporation by reference of Airbus Industrie Service Bulletin 
A300-57-6027, Revision 2, dated September 13, 1994, as listed in the 
regulations, is approved by the Director of the Federal Register as of 
October 1, 1998.
    The incorporation by reference of Airbus Industrie Service Bulletin 
No. A300-57-6027, including Appendix 1, dated October 8, 1991, as 
listed in the regulations, was previously approved by the Director of 
the Federal Register as of January 5, 1994 (58 FR 64112, December 6, 
1993).

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: 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: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 93-23-07, 
amendment 39-8741 (58 FR 64112, December 6, 1993), which is applicable 
to all Airbus Industrie Model A300-600 series airplanes, was published 
in the Federal Register on June 18, 1997 (62 FR 33040). The action 
proposed to supersede AD 93-23-07 to continue to require inspections to 
detect cracks in the center spar sealing angles adjacent to the pylon 
rear attachment and in the adjacent butt strap and skin panel, and 
correction of any discrepancies. The action proposed to require that 
the initial inspections be accomplished at reduced thresholds, and 
proposed to limit the applicability of the existing AD.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Request to Adopt ``Adjustment for Range'' Compliance Times

    One commenter, the manufacturer, requests that the proposed AD be 
revised to utilize the ``adjustment for range'' concept for required 
compliance thresholds as recommended by Airbus Industrie. The commenter 
states that, in comparison to the compliance times specified in the 
related French airworthiness directive, the compliance thresholds 
specified for paragraphs (c) and (d) of the proposed AD would 
significantly reduce compliance time for U.S. operators. The commenter 
considers this difference in the planned compliance intervals to be a 
change in the FAA's policy regarding inspections, which is not linked 
to the need to address the unsafe condition, since no technical reason 
is provided for the difference. Such a deviation is a departure from 
previously stated FAA policy, which mentions a preference for identical 
compliance times between the FAA and other airworthiness authorities 
such as the Direction Generale de l'Aviation Civile (DGAC), which is 
the airworthiness authority for France. The commenter further states 
that the proposed AD, if adopted, would unduly penalize U.S. operators 
of affected Airbus Industrie Model A300-600 series airplanes.
    The FAA does not concur. As stated in the preamble of the proposed 
AD, utilization of ``adjustment for range'' calculations may present 
difficulties in determining if the applicable actions have been 
accomplished within the appropriate compliance time. While such 
adjustable compliance times are utilized as part of the Maintenance 
Review Board program, they do not fit practically into the AD tracking 
process for operators or for Principal Maintenance Inspectors 
attempting to ascertain compliance with AD's. Based on reviews of the 
``adjustment for range'' calculations with the FAA Aircraft Evaluation 
Group, and in further consultation with the manufacturer, the FAA has 
determined that fixed compliance times should continue to be specified 
for accomplishment of the actions required by this AD. However, 
operators may request an extension of the compliance times of this AD 
in accordance with the ``adjustment for range'' formula, under the 
provisions of paragraph (g)(2) of the final rule.
    Additionally, the FAA acknowledges that a conservative estimate of 
the average flight time per flight cycle (landing) was used in 
development of the compliance times for the actions required by 
paragraphs (c) and (d) of the AD. Therefore, after additional review of 
the average flight utilization of the U.S. fleet, the FAA has 
determined that the fixed compliance thresholds may be extended 
somewhat, and that these compliance thresholds also should be specified 
in flight hours, as well as flight cycles. Accordingly, paragraphs (c) 
and (d) of the final rule have been revised to increase the compliance 
threshold specified in flight cycles, and to add a compliance threshold 
specified in flight hours. The extension of the flight cycle threshold 
is expected to provide additional flexibility for operators in planning 
for accomplishment of the required actions of this AD, and the addition 
of flight hours will not be restrictive to any U.S. operator. The cost 
impact information and Note 2 of the AD also have been revised to 
reflect these changes to the compliance thresholds and intervals of the 
final rule.

[[Page 45690]]

Request To Increase Grace Period

    One commenter requests that the grace period for accomplishment of 
the actions required by paragraph (c) of the proposed AD be increased 
from 500 to 1,000 flight cycles. This commenter states that the rule, 
as proposed, lowers the inspection threshold to 4,638 total flight 
cycles. Because its fleet of affected airplanes has already passed this 
threshold, the required actions would need to be accomplished within 
500 flight cycles after the effective date of the AD, and those actions 
cannot be accomplished in this timeframe at a line station. However, an 
increase in the grace period to 1,000 flight cycles would allow this 
operator to accomplish the required actions at a main maintenance base.
    The FAA does not concur with the request to extend the grace 
period. As discussed previously, the FAA has determined that the 
compliance threshold and intervals may be extended for accomplishment 
of the actions required by paragraphs (c) and (d) of this AD. The 
initial compliance threshold required by paragraph (c) has been revised 
from 4,638 total flight cycles to require accomplishment of the 
required actions ``Prior to accumulation of 10,600 total flight cycles 
or 22,600 total flight hours, whichever occurs first.'' With this 
extension of the compliance threshold, the FAA considers that operators 
will have adequate time to accomplish the required actions, and has 
determined that no further changes to the compliance times of the AD 
are necessary.

Conclusion

    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 described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 34 Model A300-600 series airplanes of U.S. 
registry that will be affected by this AD.
    The requirements of this AD will not add any new additional 
economic burden on affected operators, other than the costs that are 
associated with the initial inspection being required earlier than 
would have been required by AD 93-23-07 (inspection is now required 
within 10,600 total landings or 22,260 total flight hours, rather than 
12,000 total landings, for certain airplanes; and within 13,200 total 
landings or 27,720 total flight hours, rather than 15,000 total 
landings, for certain other airplanes). The current costs associated 
with AD 93-23-07 are reiterated in their entirety (as follows) for the 
convenience of affected operators.
    The costs associated with the currently required inspections entail 
8 work hours per airplane, per inspection, at an average labor rate of 
$60 per work hour. (This figure does not include the time necessary for 
gaining access and closing up.) Based on these figures, the cost impact 
of this AD on U.S. operators is estimated to be $16,320, or $480 per 
airplane, per inspection cycle.
    The cost impact figures discussed above are 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.

Regulatory Impact

    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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-8741 (58 FR 
64112, December 6, 1993), and by adding a new airworthiness directive 
(AD), amendment 39-10718, to read as follows:

98-18-02 Airbus Industrie: Amendment 39-10718. Docket 95-NM-200-AD. 
Supersedes AD 93-23-07, Amendment 39-8741.

    Applicability: Model A300-600 series airplanes, as listed in 
Airbus Service Bulletin A300-57-6027, Revision 2, dated September 
13, 1994; 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 (g) 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.

    Note 2: Paragraphs (a) and (b) of this AD restate the 
requirements for initial and repetitive inspections contained in 
paragraphs (a) and (c) of AD 93-23-07. Therefore, for operators that 
have previously accomplished at least the initial inspection in 
accordance with AD 93-23-07, paragraphs (c) and (d) of this AD 
require that the next scheduled inspection be performed within 6,000 
landings or 12,600 flight hours, whichever occurs first, after the 
last inspection performed in accordance with paragraph (a) or (c) of 
AD 93-23-07, or within 500 landings after the effective date of this 
AD, whichever occurs later.

    To prevent crack formation in the sealing angles, which could 
rupture and lead to subsequent crack formation in the bottom skin of 
the wing, and resultant reduced structural integrity of the center 
spar section of the wing, accomplish the following:

Restatement of Certain Requirements of AD 93-23-07

    (a) For those airplanes on which the modification described in 
Airbus Repair Drawing R571-40588 has not been accomplished: Perform 
high frequency eddy current (HFEC) inspections to detect cracks in 
the center spar sealing angles adjacent to Rib 8, in accordance with 
Airbus Industrie Service Bulletin No. A300-57-6027, dated

[[Page 45691]]

October 8, 1991, or Revision 2, dated September 13, 1994, at the 
time specified in paragraph (a)(1), (a)(2), or (a)(3) of this AD, as 
applicable. After the effective date of this AD, only Revision 2 of 
the service bulletin shall be used.
    (1) For airplanes that have accumulated less than 12,000 total 
landings as of January 5, 1994 (the effective date of AD 93-23-07, 
amendment 39-8741): Prior to the accumulation of 12,000 total 
landings or within 2,000 landings after January 5, 1994, whichever 
occurs later; and thereafter at intervals not to exceed 6,000 
landings until the inspections required by paragraph (c) of this AD 
are accomplished.
    (2) For airplanes that have accumulated 12,000 total landings or 
more, but less than 14,000 total landings as of January 5, 1994: 
Prior to the accumulation of 14,000 total landings or within 2,000 
landings after January 5, 1994, whichever occurs later; and 
thereafter at intervals not to exceed 6,000 landings until the 
inspections required by paragraph (c) of this AD are accomplished.
    (3) For airplanes that have accumulated 14,000 total landings or 
more as of January 5, 1994: Prior to the accumulation of 500 
landings after January 5, 1994; and thereafter at intervals not to 
exceed 6,000 landings until the inspections required by paragraph 
(c) of this AD are accomplished.
    (b) For those airplanes on which the modification specified in 
Airbus Repair Drawing R571-40588 has been accomplished: Prior to the 
accumulation of 15,000 landings after accomplishing the 
modification, or within 500 landings after January 5, 1994, 
whichever occurs later, perform a HFEC inspection to detect cracks 
in the center spar sealing angles adjacent to Rib 8, inaccordance 
with Airbus Industrie Service Bulletin No. A300-57-6027, dated 
October 8, 1991, or Revision 2, dated September 13, 1994. 
Thereafter, repeat this inspection at intervals not to exceed 6,000 
landings until the inspection required by paragraph (d) of this AD 
is accomplished.

New Requirements of this AD

    (c) For those airplanes on which Airbus Modification 08609H5276 
(Airbus Service Bulletin A300-57-6033), or the modification 
specified in Airbus Repair Drawing R571-40588 or R571-40942, has not 
been accomplished: Perform HFEC inspections to detect cracks in the 
center spar sealing angles adjacent to Rib 8, in accordance with 
Airbus Industrie Service Bulletin A300-57-6027, Revision 2, dated 
September 13, 1994, at the later of the times specified in paragraph 
(c)(1) or (c)(2), as applicable, and paragraph (c)(3) of this AD. 
Repeat the inspection thereafter at intervals not to exceed 6,000 
landings or 12,600 flight hours, whichever occurs first. 
Accomplishment of these inspections terminates the requirements of 
paragraph (a) of this AD.
    (1) For airplanes on which HFEC inspections have not been 
accomplished in accordance with AD 93-23-07: Prior to the 
accumulation of 10,600 total landings or 22,260 total flight hours, 
whichever occurs first.
    (2) For airplanes on which HFEC inspections have been 
accomplished in accordance with AD 93-23-07: Within 6,000 landings 
or 12,600 flight hours, whichever occurs first, after accomplishment 
of the last inspection performed in accordance with the requirements 
of paragraph (a) of this AD.
    (3) Within 500 landings after the effective date of this AD.
    (d) For those airplanes on which Airbus Modification 08609H5276 
(Airbus Service Bulletin A300-57-6033) or the modification specified 
in Airbus Repair Drawing R571-40588 or R571-40942 has been 
accomplished: Perform a HFEC inspection to detect cracks in the 
center spar sealing angles adjacent to Rib 8, in accordance with 
Airbus Industrie Service Bulletin No. A300-57-6027, Revision 2, 
dated September 13, 1994, at the later of the times specified in 
paragraph (d)(1) or (d)(2), as applicable, and paragraph (d)(3) of 
this AD. Repeat the inspection thereafter at intervals not to exceed 
6,000 landings or 12,600 flight hours, whichever occurs first. 
Accomplishment of this inspection terminates the requirements of 
paragraph (b) of this AD.
    (1) For airplanes on which HFEC inspections have not been 
accomplished in accordance with AD 93-23-07: Prior to the 
accumulation of 13,200 landings or 27,720 flight hours, whichever 
occurs first, after accomplishing the modification.
    (2) For airplanes on which HFEC inspections have been 
accomplished in accordance with AD 93-23-07: Within 6,000 landings 
or 12,600 flight hours, whichever occurs first, after accomplishment 
of the last inspection performed in accordance with the requirements 
of paragraph (b) of this AD.
    (3) Within 500 landings after the effective date of this AD.
    (e) If any crack is found in the center spar sealing angles, 
including cracking entirely through the sealing angle, during the 
inspections required by paragraph (a), (b), (c), or (d) of this AD: 
Prior to further flight, replace the pair of sealing angles on the 
affected wing and cold work the attachment holes, in accordance with 
Airbus Repair Drawing R571-40589 or R571-40942; and perform the 
repetitive inspections required by paragraph (c) or (d) of this AD, 
as applicable.
    (f) If any sealing angle is found to be cracked through entirely 
during the inspections required by paragraph (a), (b), (c), or (d) 
of this AD: Prior to further flight, perform additional inspections 
to detect cracks in the adjacent butt strap and skin panel, in 
accordance with paragraph 2.B.(5) of Airbus Industrie Service 
Bulletin A300-57-6027, Revision 2, dated September 13, 1994. If any 
crack is found in the adjacent butt strap and skin panel, prior to 
further flight, repair in accordance with Airbus Repair Drawing 
R571-40611.
    (g)(1) 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, 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, International 
Branch, ANM-116.
    (2) Operators may request an extension of the compliance times 
of this AD in accordance with the ``adjustment for range'' formula 
found in paragraph 1(d) of Airbus Industrie Service Bulletin A300-
57-6027, Revision 2, dated September 13, 1994. The average flight 
time per flight cycle in hours used in this formula should be for an 
individual airplane. Average flight time for a group of airplanes 
may be used if all airplanes in the group have flight times 
differing by no more than 10 percent. If compliance times are based 
on the average flight time for a group of airplanes, the individual 
airplane flight times of the group must be submitted to the Manager, 
International Branch, ANM-116, for review.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

    (h) 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.
    (i) The inspections shall be done in accordance with Airbus 
Industrie Service Bulletin No. A300-57-6027, dated October 8, 1991; 
and Airbus Industrie Service Bulletin A300-57-6027, Revision 2, 
dated September 13, 1994. Revision 2 of Airbus Industrie Service 
Bulletin A300-57-6027 contains the following list of effective 
pages:

------------------------------------------------------------------------
                                 Revision                               
                                   level                                
            Page No.             shown on        Date shown on page     
                                   page                                 
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1-7............................         2  September 13, 1994.          
8-12...........................         1  November 24, 1993.           
------------------------------------------------------------------------

    The incorporation by reference of Airbus Industrie Service 
Bulletin A300-57-6027, Revision 2, dated September 13, 1994, was 
approved by the Director of the Federal Register in accordance with 
5 U.S.C. 552(a) and 1 CFR part 51. The incorporation by reference of 
Airbus Industrie Service Bulletin No. A300-57-6027, including 
Appendix 1, dated October 8, 1991, was approved previously by the 
Director of the Federal Register as of January 5, 1994 (58 FR 64112, 
December 6, 1993). 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.

    Note 4: The subject of this AD is addressed in French 
airworthiness directive 91-253-128(B)R1, dated March 1, 1995.

    (j) This amendment becomes effective on October 1, 1998.


[[Page 45692]]


    Issued in Renton, Washington, on August 19, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-22818 Filed 8-26-98; 8:45 am]
BILLING CODE 4910-13-U