[Federal Register Volume 65, Number 73 (Friday, April 14, 2000)]
[Rules and Regulations]
[Pages 20078-20081]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-8987]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-78-AD; Amendment 39-11676; AD 2000-07-22]
RIN 2120-AA64


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 repetitive inspections to detect cracking of the doubler angle 
and discrepancies of the fasteners that connect the doubler angle and 
the bottom panel of the center wing box, and corrective actions, if 
necessary. This amendment is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified by this AD are intended to detect and 
correct fatigue cracking in the doubler angle and discrepancies of the 
fasteners that connect the doubler angle and the bottom panel of the 
center wing box. Such cracking and discrepancies could result in 
reduced structural integrity of the airplane.

DATES: Effective May 19, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 19, 2000.

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) to include an airworthiness 
directive (AD) that is applicable to certain Airbus Model A300-600 
series airplanes was published in the Federal Register on May 19, 1998 
(63 FR 27516). That action proposed to require repetitive inspections 
to detect cracking of the doubler angle and discrepancies of the 
fasteners that connect the doubler angle and the bottom panel of the 
center wing box, and corrective actions, if necessary.

Comments Received

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

No Objection to the Proposal

    One commenter, an operator, states that it does not own or operate 
the equipment affected by the proposed AD, and as such, has no comments 
to offer.

Requests To Allow Continued Flight of an Airplane With Known Cracks

    Three commenters, the manufacturer and two operators, request that 
the FAA revise the proposed AD to allow continued flight with a crack 
under 30 millimeters in length, provided that

[[Page 20079]]

repetitive inspections are accomplished. These commenters state that 
analysis has shown that the structure can sustain ultimate load with 
the pickup angle completely cracked. Two of the commenters point out 
that the doubler angle is not a principal structural element (PSE). 
These commenters suggest that the FAA follow the continued flight 
criteria and angle replacement procedures described in Airbus Service 
Bulletin A300-53-6110, dated April 8, 1997 (which was referenced in the 
proposed AD as the appropriate source of service information for 
accomplishment of the inspection, repair, and installation of new 
fasteners). One of these commenters, an operator, states that such an 
allowance would enable scheduling of repairs in a manner that will 
minimize operational impact; without such an allowance, immediate field 
repairs would cost $15 million in out-of-service and maintenance costs.
    The FAA concurs with the commenters' request to allow, under 
certain conditions, continued flight of airplanes with known cracks. 
Based on the substantiating data supplied by the commenters, and based 
on the circumstances of unusual need described above, the FAA has 
reconsidered its position regarding continued flight with known cracks 
for the affected airplanes. The FAA finds that allowing the affected 
airplanes to continue to fly with cracks that are within the limits 
specified in Airbus Service Bulletin A300-53-6110 is acceptable, 
provided that applicable corrective actions (e.g., crack stopping of 
hole, rotating probe inspection, repetitive detailed visual 
inspections, eventual modification of doubler angle) are accomplished 
as specified in Figure 1, Sheet 1, of that service bulletin. The FAA 
has revised paragraph (c) of the final rule to reflect this finding.

Request for an Alternative Method of Compliance

    One commenter suggests that, as an alternative to the modification 
required by paragraph (c) of the proposed AD, operators be allowed to 
replace the existing part with a pre-modification 11045 doubler angle 
part with the same part number. The commenter states that, unlike the 
modification, such a replacement would be more expedient because it 
would not require jacking of the airplane. The commenter also states 
that, if the subject replacement is accomplished, the inspection 
program specified in Airbus Service Bulletin A300-53-6110 would still 
be required.
    The FAA does not concur. The FAA acknowledges that the doubler 
angle could be replaced by a pre-modified 11045 part if combined with 
the inspection program specified in Airbus Service Bulletin A300-53-
6110. However, the Direction Generale de l'Aviation Civile (DGAC), 
which is the airworthiness authority for France, has not definitively 
approved such a replacement scheme. Paragraph (f) of the final rule 
contains a provision for requesting approval of an alternative method 
of compliance on a case-by-case basis. No change to the final rule is 
necessary in this regard.

Changes Made to the Proposed AD

    Since issuance of the proposed AD, Airbus Service Bulletin A300-53-
6110, Revision 01, dated December 10, 1998, has been issued. This 
revision of the service bulletin is essentially equivalent to the 
original issue, dated April 8, 1997. The FAA has revised paragraphs 
(a), (b), and (c) of the AD to require accomplishment of the actions in 
those paragraphs in accordance with Revision 01 of the service 
bulletin. However, for operators that may have accomplished required 
actions prior to the effective date of this AD in accordance with the 
original issue of the service bulletin, ``NOTE 2'' has been added to 
the final rule to give credit for such accomplishment.
    Operators should note that a fatigue rating has been added to 
Airbus Service Bulletin A300-53-6110, Revision 01, that is intended to 
allow operators to calculate an adjustable compliance threshold for 
accomplishment of the inspections described in the service bulletin. 
However, the FAA has determined that utilization of such ``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 (f) of the final rule.
    Because paragraph (c) of the final rule (which provides relief for 
corrective actions required in the event that cracking within certain 
limits is found) references paragraph (e), the FAA has revised 
paragraph (e) to address any case where a discrepancy is found during 
any inspection required by this AD and the service bulletin specifies 
to contact Airbus for appropriate action. In such a case, paragraph (e) 
requires that operators accomplish repairs prior to further flight in 
accordance with an FAA-approved method. The FAA also has determined 
that, in light of the type of actions that would be required to address 
the identified unsafe condition, and in consonance with existing 
bilateral airworthiness agreements, repair methods approved by either 
the FAA or the DGAC (or its delegated agent) would be acceptable for 
compliance with this AD. Accordingly, this provision is added to 
paragraph (e) of the final rule.
    Additionally, the FAA has added ``NOTE 3'' to the final rule to 
clarify the definition of a detailed visual inspection.

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

    The FAA estimates that 54 Model A300-600 series airplanes of U.S. 
registry will be affected by this AD, that it will take approximately 2 
work hours per airplane to accomplish the required inspections, and 
that the average labor rate is $60 per work hour. Based on these 
figures, the cost impact of the inspection proposed by this AD on U.S. 
operators is estimated to be $6,480, or $120 per airplane, per 
inspection cycle.
    The 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.

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

[[Page 20080]]

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 adding the following new 
airworthiness directive:

2000-07-22  Airbus Industrie: Amendment 39-11676. Docket 98-NM-78-
AD.

    Applicability: Model A300-600 series airplanes, on which Airbus 
Modification 11044 or Airbus Modification 11045 (reference Airbus 
Service Bulletin A300-53-6063, dated December 12, 1996) has not been 
accomplished, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (f) 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.
    To detect and correct fatigue cracking of the doubler angle and 
discrepancies of the fasteners that connect the doubler angle and 
the bottom panel of the center wing box, which could result in 
reduced structural integrity of the airplane, accomplish the 
following:

Inspections

    (a) Perform a detailed visual inspection to detect cracking of 
the doubler angle, and a detailed external visual inspection to 
detect discrepancies of the fasteners that connect the doubler angle 
and the bottom panel of the center wing box, on the left and right 
sides of the airplane, in accordance with Airbus Service Bulletin 
A300-53-6110, Revision 01, dated December 10, 1998, at the time 
specified in paragraph (a)(1) or (a)(2) of this AD, as applicable. 
Thereafter, repeat the inspections of the doubler angle and 
fasteners at intervals not to exceed 2,400 flight cycles.
    (1) For airplanes on which a detailed visual inspection has been 
performed within the last 2,400 flight cycles prior to the effective 
date of this AD, in accordance with Structural Significant Item 
(SSI) 57-10-19 of the Airbus A300-600 Maintenance Review Board (MRB) 
Document: Inspect within 2,400 flight cycles after the most recent 
SSI inspection.
    (2) For airplanes on which a detailed visual inspection has not 
been performed within the last 2,400 flight cycles prior to the 
effective date of this AD, in accordance with Structural Significant 
Item (SSI) 57-10-19 of the Airbus A300-600 Maintenance Review Board 
(MRB) Document: Inspect at the time specified in paragraph 
(a)(2)(i), (a)(2)(ii), or (a)(2)(iii), as applicable.
    (i) For airplanes that have accumulated 6,600 or more total 
flight cycles as of the effective date of this AD: Inspect within 
750 flight cycles after the effective date of this AD.
    (ii) For airplanes that have accumulated more than 3,100 total 
flight cycles, but less than 6,600 total flight cycles as of the 
effective date of this AD: Inspect within 1,500 flight cycles after 
the effective date of this AD.
    (iii) For airplanes that have accumulated 3,100 total flight 
cycles or less as of the effective date of this AD: Inspect prior to 
the accumulation of 4,600 total flight cycles.

    Note 2: Accomplishment of inspections or corrective actions 
prior to the effective date of this AD, in accordance with Airbus 
Service Bulletin A300-53-6110, dated April 8, 1997, is acceptable 
for initial compliance with the applicable paragraph of this AD.


    Note 3: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

Corrective Actions

    (b) If any discrepancy is found in a fastener that connects the 
doubler angle and the bottom panel of the center wing box during any 
detailed external visual inspection performed in accordance with 
paragraph (a) of this AD: Prior to further flight, remove the 
discrepant fastener, and perform a rotating probe inspection to 
detect discrepancies of the fastener holes, in accordance with 
Airbus Service Bulletin A300-53-6110, Revision 01, dated December 
10, 1998.
    (1) If no discrepancy is found in any fastener hole, prior to 
further flight, install a new fastener, in accordance with the 
service bulletin. Thereafter, repeat the inspections required by 
paragraph (a) of this AD at intervals not to exceed 2,400 flight 
cycles.
    (2) If any discrepancy is found in any fastener hole, prior to 
further flight, except as provided by paragraph (e) of this AD, 
repair in accordance with the service bulletin, and accomplish the 
actions required by paragraph (c) of this AD.
    (c) If any crack is found in the doubler angle during any 
detailed visual inspection performed in accordance with paragraph 
(a) of this AD, accomplish paragraph (c)(1) or (c)(2), as 
applicable, at the time specified in that paragraph.
    (1) If the cracking is within the limits specified in Figure 1, 
Sheet 1, of Airbus Service Bulletin A300-53-6110, Revision 01, dated 
December 10, 1998: Except as required by paragraph (e) of the AD, 
accomplish the applicable corrective actions (e.g., crack stopping 
of hole, rotating probe inspection, repetitive detailed visual 
inspections, eventual modification of doubler angle) specified in 
Figure 1, Sheet 1; at the times and in accordance with the 
procedures specified in the service bulletin.
    (2) If the cracking is outside the limits specified in Figure 1, 
Sheet 1 [i.e., 1.181 inches (30 millimeters) or more in length]: 
Prior to further flight, modify the doubler angle in accordance with 
Airbus Service Bulletin A300-53-6063, dated December 12, 1996. 
Accomplishment of the modification constitutes terminating action 
for the repetitive inspection requirements of this AD.

Optional Terminating Modification

    (d) Accomplishment of the modification in accordance with Airbus 
Service Bulletin A300-53-6063, dated December 12, 1996, constitutes 
terminating action for the repetitive inspection requirements of 
this AD.

Approved Repairs

    (e) If any discrepancy is found during any inspection required 
by this AD, and the service bulletin specifies to contact Airbus for 
appropriate action: Prior to further flight, repair in accordance 
with a method approved by either the Manager, International Branch, 
ANM-116, FAA, Transport Airplane Directorate, or the Direction 
Generale de l'Aviation Civile (DGAC) (or its delegated

[[Page 20081]]

agent). For a repair method to be approved by the Manager, 
International Branch, ANM-116, as required by this paragraph, the 
Manager's approval letter must specifically reference this AD.

Alternative Methods of Compliance

    (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, International Branch, ANM-116. 
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.

    Note 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (g) Special flight permits may be issued in accordance with 
Secs. 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.

Incorporation By Reference

    (h) Except as required by paragraph (e) of this AD, the actions 
shall be done in accordance with Airbus Service Bulletin A300-53-
6110, Revision 01, dated December 10, 1998, or Airbus Service 
Bulletin A300-53-6063, dated December 12, 1996; as applicable. 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.

    Note 5: The subject of this AD is addressed in French 
airworthiness directive 97-383-240(B), dated December 17, 1997.

    (i) This amendment becomes effective on May 19, 2000.

    Issued in Renton, Washington, on April 5, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-8987 Filed 4-13-00; 8:45 am]
BILLING CODE 4910-13-U