[Federal Register Volume 61, Number 127 (Monday, July 1, 1996)]
[Proposed Rules]
[Pages 33874-33876]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-16651]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-10-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300-600 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 all Airbus Model A300-600 series 
airplanes. This proposal would require inspections to detect cracking 
of the upper radius of the forward fitting of frame 47, and repair, if 
necessary. This proposal is prompted by results of full-scale fatigue 
testing, which revealed cracking in the upper radius of frame 47. The 
actions specified by the proposed AD are intended to prevent such 
fatigue cracking, which could result in reduced structural integrity of 
frame 47 of the fuselage.

DATES: Comments must be received by August 12, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-10-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: Phil Forde, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2146; fax (206) 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 96-NM-10-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-103, Attention: Rules 
Docket No.

[[Page 33875]]

96-NM-10-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, recently notified the FAA that an 
unsafe condition may exist on all Airbus Model A300-600 series 
airplanes. The DGAC advises that, during a full-scale fatigue test, 
cracks were found on the left and right upper radius of frame 47 on a 
Model A300 series airplane that had accumulated 48,000 flights. Similar 
cracking also was found on an in-service Model A300 B2 series airplane 
that had accumulated 18,000 flights. Fatigue cracking of the upper 
radius could result in rupture of the forward fitting of the frame. 
Such fatigue cracking, if not detected and corrected in a timely 
manner, could result in reduced structural integrity of frame 47 of the 
fuselage.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A300-53-6029, Revision 2, dated 
November 7, 1994, which describes procedures for repetitive eddy 
current inspections to detect cracking of the upper radius of the left 
and right forward fitting of frame 47. For airplanes on which cracking 
is found, the service bulletin describes procedures for modification of 
the sealing fitting and sealing sham, and repetitive ultrasonic 
inspections to detect cracking of the rear of the forward fitting. 
Among other things, the modification involves performing PR sealing on 
the fitting and on the fasteners inside the center wing box.
    The DGAC classified this service bulletin as mandatory and issued 
French airworthiness directive 93-162-148(B), dated September 15, 1993, 
in order to assure the continued airworthiness of these airplanes in 
France.

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 repetitive eddy 
current inspections to detect cracking of the upper radius of the left 
and right forward fitting of frame 47, and repair, if necessary. The 
inspections would be required to be accomplished in accordance with the 
service bulletin described previously. The repair would be required to 
be accomplished in accordance with a method approved by the FAA.

Explanation of Differences Between Service Bulletin and Proposed 
Rule

    Operators should note that, unlike the procedures recommended in 
the referenced service bulletin, this proposed rule would not permit 
further flight after detection of cracking in the upper radius of the 
fitting within certain limits. Instead, this proposed rule would 
require, prior to further flight, repair of cracking in accordance with 
a method approved by the FAA. The FAA finds that, in light of the 
safety implications and consequences associated with such cracking, an 
adequate level of safety for the affected fleet requires that cracking 
in the upper radius must be repaired prior to further flight.
    Additionally, this proposed AD does not require accomplishment of 
the modification described in the referenced service bulletin. The 
service bulletin specifies that purpose of the modification is to 
provide access to the forward fitting of frame 47 to enable operators 
to accomplish an ultrasonic inspection to detect longer cracks of the 
rear of the fitting. The FAA finds that since accomplishment of this 
modification will not prevent fatigue cracking of the upper radius, in 
lieu of accomplishing that modification, any cracking detected during 
the eddy current inspection must be repaired prior to further flight.
    In addition, the service bulletin specifies that inspection 
thresholds and intervals may be adjusted based on certain average 
flight operations of the airplane. However, the FAA has determined that 
such adjustments would not address the unsafe condition in a timely 
manner. Therefore, this proposed AD does not permit such adjustments. 
In developing the appropriate compliance time for the proposed rule, 
the FAA considered not only the manufacturers recommendation, but the 
safety implications involved with cracking in the upper radius of the 
fitting of frame 47 and the number of landings that had been 
accumulated when cracking was detected. In light of these factors, the 
FAA finds the compliance times specified in the proposed AD for 
initiating the required actions to be warranted, in that they represent 
an appropriate interval of time allowable for the affected airplanes to 
continue to operate without compromising safety.
    Further, the service bulletin specifies that operators need not 
count touch-and-go landings in determining the total number of landings 
between two consecutive inspections, even if those landings are less 
than five percent of the landings between inspection intervals. Since 
fatigue cracking that was found in the upper radius of the fitting of 
frame 47 is aggravated by landing operations, the FAA finds that all 
touch-and-go landings must be counted in determining the total number 
of landings between two consecutive inspections.

Cost Impact

    The FAA estimates that 35 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 actions, 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 
$8,400, or $240 per airplane.
    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

[[Page 33876]]

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 96-NM-10-AD.

    Applicability: All Model A300-600 series airplanes, 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 (b) 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 reduced structural integrity of frame 47 of the 
fuselage, accomplish the following:
    (a) Prior to the accumulation of 17,300 total landings, or 
within one year after the effective date of this AD, whichever 
occurs later: Perform an eddy current inspection to detect cracking 
of the upper radius of the left and right forward fitting of frame 
47, in accordance with Airbus Service Bulletin A300-53-6029, 
Revision 2, dated November 7, 1994.
    (1) If no cracking is found during an eddy current inspection: 
Repeat the inspection thereafter at intervals not to exceed 6,600 
landings.
    (2) If any cracking is found during an eddy current inspection: 
Prior to further flight, repair in accordance with a method approved 
by the Manager, Standardization Branch, ANM-113, FAA, Transport 
Airplane Directorate.
    (b) 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, Standardization Branch, ANM-113. 
Operators shall submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, Standardization Branch, ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.
    (c) 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.

    Issued in Renton, Washington, on June 25, 1996.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-16651 Filed 6-28-96; 8:45 am]
BILLING CODE 4910-13-P