[Federal Register Volume 64, Number 175 (Friday, September 10, 1999)]
[Proposed Rules]
[Pages 49110-49112]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-23477]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-184-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A330 and A340 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 A330 and A340 
series airplanes. This proposal would require repetitive detailed 
visual inspections to detect cracking of the vertical flange of the 
inboard Z-stiffeners of the centerline panel of the fuselage belly 
fairing; and corrective actions, if necessary. This proposed AD also 
provides for optional terminating action for the repetitive 
inspections. 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 fatigue cracking of the vertical flange of the 
inboard Z-stiffeners of the centerline panel of the fuselage belly 
fairing, which could result in reduced structural integrity of the 
belly fairing.

DATES: Comments must be received by October 12, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-184-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 
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-184-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-184-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 A330 and A340 series 
airplanes. The DGAC advises that during full-scale fatigue testing, 
fatigue cracking occurred in one of the inboard Z-stiffeners at the 
fitting retaining the centerline panel between the main landing gear 
doors. The cracking initiated in the cut-out radius of the vertical 
flange and propagated downward. Such fatigue cracking, if not detected 
and corrected, could result in reduced structural integrity of the 
belly fairing.

Explanation of Relevant Service Information

    The manufacturer has issued Airbus Service Bulletins A330-53-3020 
(for Model A330 series airplanes) and A340-53-4029 (for Model A340 
series airplanes); each dated November 30, 1995. These service 
bulletins describe procedures for repetitive detailed visual 
inspections to detect cracking of the vertical flange of the inboard Z-
stiffeners of the centerline panel of the fuselage belly fairing; and 
corrective actions, if necessary. The detailed visual inspection 
includes the left- and right-hand sides of the centerline panel between 
the main landing gear doors. The corrective actions reference the 
accomplishment of Airbus Service Bulletin A330-53-3019 (for Model A330 
series airplanes) or A340-53-4028 (for Model A340 series airplanes); 
each dated November 30, 1995. These service bulletins describe 
procedures for modification of the vertical flange of the inboard Z-
stiffeners of the centerline panel of the fuselage belly fairing. The 
modification involves the installation of a new cut-out of the vertical 
flange of the inboard Z-stiffeners; and installation of an external 
reinforcement plate (strap), and modification of the assembly (length 
of fasteners) between the Z-stiffeners and the belly fairing panel.
    Accomplishment of the modification of the vertical flange of the 
inboard Z-stiffeners of the centerline panel of the fuselage belly 
fairing eliminates the need for the repetitive inspections, provided 
that all cracking is eliminated. Accomplishment of the actions 
specified in the applicable service bulletins is intended to adequately 
address the identified unsafe condition. The DGAC classified Airbus 
Service Bulletins A330-53-3020 and A340-53-4029 as mandatory and issued 
French airworthiness directives 96-056-029 (B) (for Model A330 series 
airplanes), and 96-057-042 (B) (for Model A340 series airplanes); each 
dated March 13, 1996; in order to assure the continued airworthiness of 
these airplanes in France.

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

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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, this 
proposed AD would require accomplishment of the actions specified in 
the service bulletins described previously, except as discussed below. 
This proposed AD also would provide for optional terminating action for 
the repetitive inspections.
    Operators should note that, in consonance with the findings of the 
DGAC, the FAA has determined that the repetitive inspections proposed 
by this AD can be allowed to continue in lieu of accomplishment of a 
terminating action. In making this determination, the FAA considers 
that, in this case, long-term continued operational safety will be 
adequately assured by accomplishing the repetitive inspections to 
detect cracking before it represents a hazard to the airplane.

Differences Between Proposed Rule and Service Bulletin

    Unlike the procedures described in Airbus Service Bulletins A330-
53-3020 (for Model A330 series airplanes) and A340-53-4029 (for Model 
A340 series airplanes), this proposed AD would not permit further 
flight if cracks are detected of the vertical flange of the inboard Z-
stiffeners of the centerline panel of the fuselage belly fairing. The 
FAA has determined that, because of the safety implications and 
consequences associated with such cracking, any vertical flange of the 
inboard Z-stiffener that is found to be cracked must be repaired or 
modified to eliminate any cracking, or repaired (for any cracking that 
cannot be eliminated), prior to further flight.
    Operators also should note that, although the service bulletins 
specify that the manufacturer may be contacted for disposition of 
certain cracking conditions, this proposal would require the repair of 
those conditions to be accomplished in accordance with a method 
approved by the FAA.

Cost Impact

    None of the airplanes affected by this action are on the U.S. 
Register. All airplanes included in the applicability of this proposed 
rule currently are operated by non-U.S. operators under foreign 
registry; therefore, they are not directly affected by this proposed AD 
action. However, the FAA considers that this proposed rule is necessary 
to ensure that the unsafe condition is addressed in the event that any 
of these subject airplanes are imported and placed on the U.S. Register 
in the future.
    Should an affected airplane be imported and placed on the U.S. 
Register in the future, it would require approximately 1 work hour to 
accomplish the proposed inspection, at an average labor rate of $60 per 
work hour. Based on these figures, the cost impact of this AD would be 
$60 per airplane, per inspection cycle.
    Should an operator elect to accomplish the optional terminating 
action proposed by this AD, it would require approximately 7 work hours 
to accomplish the proposed optional terminating action, at an average 
labor rate of $60 per work hour. Required parts would cost 
approximately $2,350 per airplane. Based on these figures, the cost 
impact of the optional terminating action is estimated to $2,770 per 
airplane.

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 99-NM-184-AD.

    Applicability: Model A330 and A340 series airplanes; except 
those airplanes on which Airbus Modification 42605, or Airbus 
Service Bulletin A330-53-3019 (for Model A330 series airplanes) or 
A340-53-4028 (for Model A340 series airplanes) has 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 (c) 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 vertical flange of 
the inboard Z-stiffeners of the centerline panel of the fuselage 
belly fairing, which could result in reduced structural integrity of 
the belly fairing, accomplish the following:

Repetitive Detailed Visual Inspections

    (a) Prior to the accumulation of 5,500 total flight cycles, or 
within 500 flight hours after the effective date of this AD, 
whichever occurs later, perform a detailed visual inspection to 
detect cracking of the vertical flange of the inboard Z-stiffeners 
of the centerline panel of the fuselage belly fairing, in accordance 
with Airbus Service Bulletin A330-53-3020 (for Model A330 series 
airplanes) or A340-53-4029 (for Model A340 series airplanes); each 
dated November 30, 1995; as applicable.

    Note 2: 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.''


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    (1) If no cracking is detected, repeat the inspection thereafter 
at intervals not to exceed 5,500 flight cycles, until the 
requirements of paragraph (b) of this AD are accomplished.

Corrective Actions

    (2) If any cracking is detected during any inspection required 
by this AD, prior to further flight, modify the vertical flange of 
both inboard Z-stiffeners of the centerline panel of the fuselage 
belly fairing and re-inspect the modified area to determine if 
cracking has been eliminated, in accordance with Airbus Service 
Bulletin A330-53-3019 (for Model A330 series airplanes) or A340-53-
4028 (for Model A340 series airplanes); each dated November 30, 
1995; as applicable.
    (i) If all cracking is not eliminated after accomplishment of 
the modification, 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 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.
    (ii) If all cracking is eliminated after the accomplishment of 
the modification, no further action is required by this AD.

Optional Terminating Action

    (b) Modification of the vertical flange of both inboard Z-
stiffeners of the centerline panel of the fuselage belly fairing in 
accordance with Airbus Service Bulletin A330-53-3019 (for Model A330 
series airplanes) or A340-53-4028 (for Model A340 series airplanes); 
each dated November 30, 1995; as applicable constitutes terminating 
action for the requirements of this AD.

Alternative Methods of Compliance

    (c) 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.

Special Flight Permits

    (d) 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 French airworthiness 
directives 96-056-029 (B) and 96-057-042 (B); each dated March 13, 
1996; in order to assure the continued airworthiness of these 
airplanes in France.

    Issued in Renton, Washington, on September 2, 1999.
Dorenda D. Baker,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-23477 Filed 9-9-99; 8:45 am]
BILLING CODE 4910-13-U