[Federal Register Volume 64, Number 203 (Thursday, October 21, 1999)]
[Proposed Rules]
[Pages 56712-56715]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-27565]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-248-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300 B2 and B4 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 certain Airbus Model A300 B2 and 
B4 series airplanes. This proposal would require repetitive inspections 
to detect cracking of the inner skin panel of the longitudinal lap 
joint; and repair, or modification and new repetitive inspections, if 
necessary. This proposal is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified by the proposed AD are intended to 
detect and correct stress corrosion cracking of the inner skin panel of 
the longitudinal lap joint, which could result in rapid 
depressurization of the airplane.

DATES: Comments must be received by November 22, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-248-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: 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:

Comments Invited

    Interested persons are invited to participate in the making of the

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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 98-NM-248-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-114, Attention: Rules 
Docket No. 98-NM-248-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, notified the FAA that an unsafe 
condition may exist on certain Airbus Model A300 B2 and B4 series 
airplanes. The DGAC advises that, on four in-service Airbus Model A300 
series airplanes, cracking of the inner skin panel of the longitudinal 
lap joint was detected between frames 67 and 70 at stringer 57. The 
cracking of the fuselage skin panel was attributed to stress corrosion. 
On two of the airplanes, corrosion was found previously in the long lap 
joints, and those areas were reworked beyond the limits provided in the 
Airbus A300 Structural Repair Manual. Subsequent stress corrosion 
cracking is attributed to the improper rework. Such cracking of the 
inner skin panel of the longitudinal lap joint, if not corrected, could 
result in rapid depressurization of the airplane.

Explanation of Relevant Service Information

    The manufacturer has issued Airbus Service Bulletin A300-53-305, 
Revision 1, dated January 29, 1999. That service bulletin describes 
procedures for repetitive external and internal eddy current 
inspections to detect cracking of the inner skin panel of the 
longitudinal lap joint between frames 65 and 72 at stringer 57, and 
repair, if necessary. For repaired areas, the service bulletin also 
specifies new repetitive inspections. The DGAC classified the service 
bulletin as mandatory and issued French airworthiness directive 98-150-
246(B), dated April 8, 1998, in order to assure the continued 
airworthiness of these airplanes in France.
    The manufacturer also has issued Airbus Service Bulletin A300-53-
306, dated September 5, 1995, which describes procedures for 
modification of the inner skin panel of the longitudinal lap joint 
between frames 65 and 72 at stringer 57 by installation of a doubler. 
That modification is intended to delay the onset of cracking of the 
inner skin panel of the longitudinal lap joint, and would eliminate the 
need to accomplish the repetitive inspections described in Airbus 
Service Bulletin A300-53-305, Revision 1, for all modified areas.
    The manufacturer also has issued Airbus Service Bulletin A300-53-
211, Revision 5, dated April 29, 1999. That service bulletin describes 
inspection criteria to detect cracking of, among other areas, the inner 
skin panel of the longitudinal lap joint between frames 65 and 72 at 
stringer 57 after it has been modified in accordance with Airbus 
Service Bulletin A300-53-306.

FAA's Conclusions

    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.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the service bulletins described previously, 
except as discussed below.

Difference Between Proposed Rule and Service Bulletins

    Operators should note that, unlike the procedures described in 
Airbus Service Bulletin A300-53-305, Revision 1, and Airbus Service 
Bulletin A300-53-211, Revision 5, this proposed AD would not permit 
further flight if a crack is detected in the inner skin panel of the 
longitudinal lap joint. The FAA has determined that, because of the 
safety implications and consequences associated with such cracking, any 
subject inner skin panel that is found to be cracked must be repaired 
or modified prior to further flight.

Difference Between Proposed Rule and Foreign Airworthiness 
Directive

    Operators should note that, although French airworthiness directive 
98-150-246(B) states that no inspections in accordance with that 
airworthiness directive are necessary after accomplishment of Airbus 
Service Bulletin A300-53-306, this proposed AD would require repetitive 
inspections in accordance with Airbus Service Bulletin A300-53-211, 
Revision 5, for areas modified in accordance with Airbus Service 
Bulletin A300-53-306. The modification described in Airbus Service 
Bulletin A300-53-306 is intended to delay the onset of cracking of the 
inner skin panel of the longitudinal lap joint. However, cracking may 
still occur in the modified area. The FAA finds that repetitive 
inspections of the modified area are necessary to ensure that any 
cracking is detected in a timely manner.

Other Relevant Rulemaking

    On May 28, 1996, the FAA issued AD 96-12-02, Amendment 39-9644 (61 
FR 28497, June 5, 1996). The applicability statement of that AD is the 
same as for this proposed AD. That AD requires measurements of the 
thickness of the inner skin of, and inspections to detect cracking of, 
the longitudinal lap joint from the inside of the fuselage at certain 
stringers, and repair, if necessary, in accordance with Airbus All 
Operator Telex (AOT) 53-05, Revision 1, dated August 16, 1993. Airbus 
Service Bulletin A300-53-305, Revision 1, specifies separate compliance 
times for airplanes on which Airbus AOT 53-05, Revision 1, has been 
accomplished. Because the actions specified in that AOT are already 
required by AD 96-12-02, this proposed AD does not specify compliance 
times for airplanes on

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which the AOT has not been accomplished.

Cost Impact

    The FAA estimates that 3 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 4 work 
hours per airplane to accomplish the proposed eddy current inspection 
(either internal or external), and that the average labor rate is $60 
per work hour. Based on these figures, the cost impact of the proposed 
AD on U.S. operators is estimated to be $720, or $240 per airplane, per 
inspection cycle.
    The 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.

Regulatory Impact

    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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

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

Airbus Industrie: Docket 98-NM-248-AD.

    Applicability: Model A300 B2 and B4 series airplanes, 
manufacturer serial numbers 003 through 156 inclusive; 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 (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 stress corrosion cracking of the inner 
skin panel of the longitudinal lap joint, which could result in 
rapid depressurization of the airplane, accomplish the following:

Initial Inspection

    (a) Within 400 flight cycles after the effective date of this 
AD, perform an external eddy current inspection for cracking of the 
inner skin panel of the longitudinal lap joint between frames 65 and 
72 at stringer 57, in accordance with Airbus Service Bulletin A300-
53-305, Revision 1, dated January 29, 1999.

Repetitive Inspections

    (b) If no cracking is detected during the inspection performed 
in accordance with paragraph (a) of this AD: Thereafter, perform an 
internal or external eddy current inspection, as specified in 
paragraphs (b)(1) and (b)(2) of this AD, as applicable; at intervals 
not to exceed 1,250 flight cycles or 7 months, whichever occurs 
first; in accordance with Airbus Service Bulletin A300-53-305, 
Revision 1, dated January 29, 1999; until the requirements of 
paragraph (e) of this AD have been accomplished.
    (1) If the most recent inspection was an internal eddy current 
inspection, perform an external eddy current inspection of the inner 
skin panel of the longitudinal lap joint.
    (2) If the most recent inspection was an external eddy current 
inspection, perform an internal eddy current inspection of the inner 
skin panel of the longitudinal lap joint.

Corrective Actions

    (c) If any cracking is detected during any inspection performed 
in accordance with paragraph (a) or (b) of this AD, prior to further 
flight, accomplish the actions required by either paragraph (c)(1) 
or paragraph (c)(2) of this AD.
    (1) Repair the inner skin panel of the longitudinal lap joint in 
accordance with Airbus Service Bulletin A300-53-305, Revision 1, 
dated January 29, 1999. Thereafter, repeat the inspection of areas 
in which no cracking is detected at the interval specified in, and 
in accordance with, paragraph (b) of this AD; and repeat the 
inspection of the repaired area at the intervals specified in the 
service bulletin, in accordance with the service bulletin. If any 
cracking is found in the repaired area during any repetitive 
inspection, prior to further flight, repair in accordance with the 
service bulletin.

    Note 2: Airbus Service Bulletin A300-53-305, Revision 1, dated 
January 29, 1999, references Airbus Structural Repair Manual Chapter 
53-17-00, as an additional source of service information to 
accomplish the repair specified in paragraph (c)(1) of this AD.

    (2) Modify the inner skin panel of the longitudinal lap joint in 
accordance with Airbus Service Bulletin A300-53-306, dated September 
5, 1995, and accomplish the requirements of paragraph (d) of this 
AD.
    (d) For airplanes modified in accordance with Airbus Service 
Bulletin A300-53-306, dated September 5, 1995: Inspect the modified 
inner skin panel of the longitudinal lap joint to detect cracking at 
the applicable threshold and repetitive intervals specified in Table 
1A, 1B, or 2 of Airbus Service Bulletin A300-53-211, Revision 5, 
dated April 29, 1999, in accordance with Airbus Service Bulletin 
A300-53-211, Revision 5. If any cracking is found during any 
repetitive inspection, prior to further flight, repair in accordance 
with Airbus Service Bulletin A300-53-211, Revision 5.

Optional Modification

    (e) Modification of the inner skin panel of the longitudinal lap 
joint in accordance with Airbus Service Bulletin A300-53-306, dated 
September 5, 1995, constitutes terminating action for the repetitive 
inspections required by paragraph (b) of this AD. Such modification 
does not terminate the repetitive inspections required by paragraph 
(d) of this AD.

Alternative Method 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 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.

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Special Flight Permits

    (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.

    Note 4: The subject of this AD is addressed in French 
airworthiness directive 98-150-246(B), dated April 8, 1998.

    Issued in Renton, Washington, on October 15, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-27565 Filed 10-20-99; 8:45 am]
BILLING CODE 4910-13-P