[Federal Register Volume 65, Number 77 (Thursday, April 20, 2000)]
[Proposed Rules]
[Pages 21154-21157]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-9898]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-240-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Industrie Model A300, A300-600, 
and A310 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Airbus Model A300, 
A300-600, and A310 series airplanes, that currently requires 
inspections to detect cracks in the lower spar axis of the nacelle 
pylon between ribs 9 and 10, and repair, if necessary. The existing AD 
also provides for optional modification of the pylon, which terminates 
the inspections for Model A300 and A310

[[Page 21155]]

series airplanes and increases the threshold and repetitive interval of 
the inspections for Model A300-600 series airplanes. This action would 
reduce the inspection threshold and require repetitive inspections 
following accomplishment of the optional modification for Model A310 
series airplanes. 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 
prevent fatigue cracking, which could result in reduced structural 
integrity of the lower spar of the pylon.

DATES: Comments must be received by May 22, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-240-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays.
    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 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 
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 99-NM-240-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. 99-NM-240-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On April 28, 1995, the FAA issued AD 95-10-03, amendment 39-9220 
(60 FR 25604, May 12, 1995), applicable to certain Airbus Industrie 
Model A300, A300-600, and A310 series airplanes, to require inspections 
to detect cracks in the lower spar axis of the nacelle pylon between 
ribs 9 and 10, and repair, if necessary. The existing AD also provides 
for optional modification of the pylon, which terminates the 
inspections for Model A300 and A310 series airplanes and increases the 
threshold and repetitive interval of the inspections for Model A300-600 
series airplanes. That action was prompted by reports that fatigue 
cracks have been found between ribs 9 and 10 on the lower spar of the 
pylon, initiating at the center stiffener beyond the flat area. The 
requirements of that AD are intended to prevent such fatigue cracking, 
which could result in reduced structural integrity of the lower spar of 
the pylon.

Actions Since Issuance of Previous Rule

    Since issuance of AD 95-10-03, the Direction Generale de l'Aviation 
Civile (DGAC), which is the airworthiness authority for France, has 
advised the FAA that additional cracks have been found in the lower 
spar axis of the nacelle pylon between ribs 9 and 10 on Model A310 
series airplanes at a lower total number of flight cycles than had been 
earlier reported. Based on these findings, the FAA has determined that, 
for Airbus Model A310 series airplanes, it is necessary to reduce the 
inspection threshold and, for airplanes on which the optional 
modification has been accomplished, to require that the inspections be 
repetitively performed.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A310-54-2016, Revision 02, dated 
June 11, 1999 (for Model A310 series airplanes). The actions described 
in Revision 02 of this service bulletin are identical to those 
described in the original version and Revision 01 (which were cited as 
appropriate service information for accomplishment of the inspections). 
Revision 02 was issued to reduce the initial inspection threshold and, 
for airplanes modified in accordance with Service Bulletin A310-54-
2022, Revision 1, dated March 16, 1999, to specify that the inspection 
be repetitively performed.
    The DGAC classified Service Bulletin A310-54-2016 as mandatory and 
issued French airworthiness directive 1999-237-285(B), dated June 2, 
1999, in order to assure the continued airworthiness of these airplanes 
in France. French airworthiness directive 1992-049-130(B) R4 was issued 
to remove Model A310 series airplanes from its applicability and to 
advise of the issuance of airworthiness directive 1999-237-285(B).

FAA's Conclusions

    These airplane models are manufactured in France and are 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 supersede AD 95-10-03 to 
continue to require inspections to detect cracks in the lower spar axis 
of the nacelle pylon between ribs 9 and 10, and repair, if necessary. 
The proposed AD would continue to provide for optional modification of 
the pylon; for Model A300 series airplanes, accomplishment of the 
modification would terminate the inspections; for Model A300-600 and 
A310 series airplanes, such

[[Page 21156]]

modification would increase the threshold and repetitive interval of 
the inspections.

Differences Between Proposed Rule and Service Bulletins

    Operators should note that, although the service bulletins specify 
that the manufacturer may be contacted for disposition of certain 
repair conditions, this proposal would require the repair of those 
conditions to be accomplished in accordance with a method approved by 
either the FAA, or the DGAC (or its delegated agent). In light of the 
type of repair that would be required to address the identified unsafe 
condition, and in consonance with existing bilateral airworthiness 
agreements, the FAA has determined that, for this proposed AD, a repair 
approved by either the FAA or the DGAC would be acceptable for 
compliance with this proposed AD.

Cost Impact

    The FAA estimates that 140 airplanes of U.S. registry will be 
affected by this AD.
    It will take approximately 4 work hours per airplane to accomplish 
the inspection that was previously required by AD 95-10-03, and 
retained in this AD, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the inspection on U.S. 
operators is estimated to be $240 per airplane, per inspection 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.
    Should an operator elect to accomplish the proposed optional 
modification, it would take approximately 104 work hours (52 work hours 
per pylon) to accomplish it, at an average labor rate of $60 per work 
hour. The cost of required parts would be approximately $1,200 per 
airplane. Based on these figures, the total cost impact of the optional 
modification is estimated to be $7,440 per airplane.

Regulatory Impact

    The regulations proposed herein would not have a substantial direct 
effect 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, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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 removing amendment 39-9220 (60 FR 
25604, May 12, 1995), and by adding the following new airworthiness 
directive (AD), to read as follows:

Airbus Industrie: Docket 99-NM-240-AD. Supersedes AD 95-10-03, 
Amendment 39-9220.

    Applicability: The following airplanes, certificated in any 
category:

 Model A300 series airplanes, as listed in Airbus Service 
Bulletin A300-54-071, Revision 1, dated October 15, 1993
 Model A300-600 series airplanes, as listed in Airbus 
Service Bulletin A300-54-6011, Revision 1, dated October 15, 1993
 Model A310 series airplanes, as listed in Airbus Service 
Bulletin A310-54-2016, Revision 02, dated June 11, 1999

    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 (e) 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 prevent fatigue cracking, which could result in reduced 
structural integrity of the lower spar of the pylon, accomplish the 
following:

Restatement of Certain Requirements of AD  95-10-03

Model A300 Series Airplanes

    (a) For Model A300 B4-2C, B2K-3C, B2-203, B4-103, and B4-203 
series airplanes: Prior to the accumulation of 9,000 total landings, 
or within 500 landings after June 12, 1995 (the effective date of AD 
95-10-03, amendment 39-9220), whichever occurs later, perform an 
internal eddy current inspection to detect cracks in the lower spar 
axis of the pylon between ribs 9 and 10, in accordance with Airbus 
Industrie Service Bulletin A300-54-071, dated November 12, 1991; or 
Revision 1, dated October 15, 1993.
    (1) If no crack is found, repeat the inspection thereafter at 
intervals not to exceed 2,500 landings.
    (2) If any crack is found that is less than or equal to 30 mm: 
Perform subsequent inspections and repair in accordance with the 
methods and times specified in the service bulletin.
    (3) If any crack is found that is greater than 30 mm, but less 
than 100 mm: Prior to the accumulation of 250 landings after crack 
discovery, repair in accordance with a method approved by the 
Manager, International Branch, ANM-116, FAA, Transport Airplane 
Directorate; or the Direction Generale de l'Aviation Civile (DGAC) 
(or its delegated agent).
    (4) If any crack is found that is greater than or equal to 100 
mm: Prior to further flight, repair in accordance with a method 
approved by the Manager, International Branch, ANM-116; or the DGAC 
(or its delegated agent).
    (5) Accomplishment of the modification specified in Airbus 
Industrie Service Bulletin A300-54-0079, dated October 15, 1993, 
constitutes terminating action for the inspections required by 
paragraph (a) of this AD.

Model A300-600 Series Airplanes

    (b) For Model A300-600 B4-620, C4-620, B4-622R, and B4-622 
series airplanes: Except as provided by paragraph (b)(5) of this AD, 
prior to the accumulation of 4,000 total landings, or within 500 
landings after June 12, 1995 (the effective date of AD 95-10-03), 
whichever occurs later, perform an internal eddy current inspection 
to detect cracks in the lower spar axis of the pylon between ribs 9 
and 10, in accordance with Airbus Industrie Service Bulletin A300-
54-6011, dated November 12, 1991, as amended by Service Bulletin 
Change Notice O.A., dated July 10, 1992; or Revision 1, dated 
October 15, 1993.
    (1) If no crack is found, repeat the inspection thereafter at 
intervals not to exceed 2,500 landings.
    (2) If any crack is found that is less than or equal to 30 mm: 
Perform subsequent inspections and repair in accordance with

[[Page 21157]]

the methods and times specified in the service bulletin.
    (3) If any crack is found that is greater than 30 mm, but less 
than 100 mm: Prior to the accumulation of 250 landings after crack 
discovery, repair in accordance with a method approved by the 
Manager, International Branch, ANM-116; or the Direction Generale de 
l'Aviation Civile (DGAC) (or its delegated agent).
    (4) If any crack is found that is greater than or equal to 100 
mm: Prior to further flight, repair in accordance with a method 
approved by the Manager, International Branch, ANM-116; or the DGAC 
(or its delegated agent).
    (5) Accomplishment of the modification specified in Airbus 
Industrie Service Bulletin A300-54-6019, dated October 15, 1993, 
increases the threshold and repetitive interval of the inspections 
required by paragraph (b) of this AD to the threshold and interval 
specified in paragraph 2.D. of the Accomplishment Instructions of 
Airbus Industrie Service Bulletin A300-54-6011, Revision 1, dated 
October 15, 1993.

New Requirements of This AD

Model A310 Series Airplanes

    (c) For Model A310-221, -222, -322, -324, and -325 series 
airplanes: Perform an internal eddy current inspection to detect 
cracks in the lower spar axis of the pylon between ribs 9 and 10, in 
accordance with Airbus Industrie Service Bulletin A310-54-2016, 
dated November 12, 1991; or Revision 1, dated October 15, 1993; or 
Revision 2, dated June 11, 1999; at the time specified in paragraph 
(d) of this AD.
    (1) If no crack is found, repeat the inspection thereafter at 
intervals not to exceed 2,500 landings.
    (2) If any crack is found that is less than or equal to 30 mm: 
Perform subsequent inspections and repair in accordance with the 
methods and times specified in the service bulletin.
    (3) If any crack is found that is greater than 30 mm, but less 
than 100 mm: Prior to the accumulation of 250 landings after crack 
discovery, repair in accordance with a method approved by the 
Manager, International Branch, ANM-116; or the DGAC (or its 
delegated agent).
    (4) If any crack is found that is greater than or equal to 100 
mm: Prior to further flight, repair in accordance with a method 
approved by the Manager, International Branch, ANM-116; or the DGAC 
(or its delegated agent).
    (5) Accomplishment of the modification specified in Airbus 
Industrie Service Bulletin A310-54-2022, dated October 15, 1993; or 
Revision 1, dated March 16, 1999; increases the threshold and 
repetitive interval of the inspections required by paragraph (c) of 
this AD to the threshold and interval specified in paragraph 2.D. of 
the Accomplishment Instructions of Airbus Industrie Service Bulletin 
A310-54-2016, Revision 02, dated June 11, 1999.
    (d) Perform the initial inspection required by paragraph (c) of 
this AD at the earlier of the times specified by paragraphs (d)(1) 
and (d)(2) of this AD.
    (1) Prior to the accumulation of 25,000 total landings, or 
within 500 landings after June 12, 1995, whichever occurs later.
    (2) At the applicable time specified by paragraph (d)(2)(i), 
(d)(2)(ii), or (d)(2)(iii) of this AD.
    (i) For airplanes that have accumulated fewer than 10,000 
landings as of the effective date of this AD: Perform the inspection 
prior to the accumulation of 3,800 total landings, or within 1,500 
landings after the effective date of this AD, whichever occurs 
later.
    (ii) For airplanes that have accumulated 10,000 total landings 
or more, but fewer than 20,000 total landings, as of the effective 
date of this AD: Perform the inspection within 1,000 landings after 
the effective date of this AD.
    (iii) For airplanes that have accumulated 20,000 total landings 
or more as of the effective date of this AD: Perform the inspection 
within 500 landings after the effective date of this AD.

Alternative Methods of Compliance

    (e) 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.

    Note 2: 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

    (f) 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 3: The subject of this AD is addressed in French 
airworthiness directive 1999-237-285(B), dated June 2, 1999.


    Issued in Renton, Washington, on April 14, 2000.
Charles D. Huber,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-9898 Filed 4-19-00; 8:45 am]
BILLING CODE 4910-13-P