[Federal Register Volume 65, Number 76 (Wednesday, April 19, 2000)]
[Proposed Rules]
[Pages 20922-20924]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-9822]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-54-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus 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 adoption of a new airworthiness 
directive (AD) that is applicable to certain Airbus Model A300, A300-
600, and A310 series airplanes. This proposal would require replacement 
of the transformer rectifier units (TRU) in the avionics compartment 
with new, improved TRU's. This proposal is prompted by issuance of 
mandatory continuing airworthiness information by a foreign civil 
airworthiness authority.

[[Page 20923]]

The actions specified by the proposed AD are intended to prevent 
failure of the TRU's. Failure of multiple TRU's could result in loss of 
the thrust reversers, autothrottle, flaps, and various systems (wing/
cockpit window anti-ice, trim tank pumps, and windshield wipers) on the 
airplane; or incorrect information displayed to the flight crew.

DATES: Comments must be received by May 19, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-54-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 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, 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 2000-NM-54-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. 2000-NM-54-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, A300-600, and A310 
series airplanes. The DGAC advises that it has received reports of 
failures in operation of the direct current (DC) electrical power 
transformer rectifier units (TRU). Investigation of these failures 
revealed that the temperature level that triggers the fan may lead to 
the overheat and failure of one or more TRU's. Failure of multiple 
TRU's, if not corrected, could result in loss of the thrust reversers, 
autothrottle, flaps, and various systems (wing/cockpit window anti-ice, 
trim tank pumps, and windshield wipers) on the airplane; or incorrect 
information displayed to the flight crew.

Explanation of Relevant Service Information

    The manufacturer has issued Airbus Service Bulletin A300-24-0089, 
dated March 4, 1998 (for Model A300 series airplanes), A300-24-6068, 
dated January 28, 1998 (for Model A300-600 series airplanes), and A310-
24-2077, dated January 21, 1998 (for Model A310 series airplanes). 
These service bulletins describe procedures for replacement of the 
TRU's in the avionics compartment with new, improved TRU's. The new 
TRU's utilize a reduced working temperature, thus improving the 
reliability of the TRU's. The DGAC classified these service bulletins 
as mandatory and issued French airworthiness directive 1999-435-296(B), 
dated November 3, 1999, in order to assure the continued airworthiness 
of these airplanes in France.
    The Airbus service bulletins reference AUXILEC Service Bulletin 
F11QB3121-24-007, dated February 2, 1998, as an additional source of 
service information for accomplishing the replacement proposed by this 
AD.

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 require replacement of the 
TRU's in the avionics compartment with new, improved TRU's. The actions 
would be required to be accomplished in accordance with the service 
bulletins described previously, except as discussed below.

Differences Between Proposed Rule and Foreign Airworthiness 
Directive

    The proposed rule would differ from the French airworthiness 
directive in that it would require accomplishment of the replacement 
described previously, within 6 months after the effective date of this 
AD. The parallel French airworthiness directive specifies 
accomplishment of the replacement prior to September 30, 2001 (18 
months after the effective date). In developing an appropriate 
compliance time for this AD, the FAA considered not only the DGAC's and 
the manufacturer's recommendations, but the degree of urgency 
associated with addressing the subject unsafe condition and the average 
utilization of the affected fleet. In light of these factors, the FAA 
finds a 6-month compliance time for the required actions to be 
warranted, in that it represents an appropriate interval of time 
allowable for affected airplanes to continue to operate without 
compromising safety.

Cost Impact

    The FAA estimates that 122 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 2 work 
hours per airplane to accomplish the proposed replacement, and that the 
average labor rate is $60 per work hour. Required

[[Page 20924]]

parts would be provided by the manufacturer at no cost to the operators 
if modification of the TRU's is accomplished at the vendor's (AUXILEC) 
facilities, otherwise the required parts would cost approximately $253 
per TRU. Based on these figures, the cost impact of the proposed AD on 
U.S. operators is estimated to be between $120 and $1,132 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 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 adding the following new 
airworthiness directive:

Airbus Industrie: Docket 2000-NM-54-AD.

    Applicability: Model A300, A300-600, and A310 series airplanes; 
certificated in any category; equipped with AUXILEC transformer 
rectifier units (TRU) having part number (P/N) F11QB3121.

    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 (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 prevent failure of multiple TRU's, which could result in loss 
of the thrust reversers, autothrottle, flaps, and various systems 
(wing/cockpit window anti-ice, trim tank pumps, and windshield 
wipers) on the airplane; or incorrect information displayed to the 
flight crew; accomplish the following:

Replacement

    (a) Within 6 months after the effective date of this AD, replace 
the TRU's in the avionics compartment with new, improved TRU's, in 
accordance with Airbus Service Bulletins A300-24-0089, dated March 
4, 1998 (for Model A300 series airplanes); A300-24-6068, dated 
January 28, 1998 (for Model A300-600 series airplanes); or A310-24-
2077, dated January 21, 1998 (for Model A310 series airplanes); as 
applicable.

    Note 2: The Airbus service bulletins reference AUXILEC Service 
Bulletin F11QB3121-24-007, dated February 2, 1998, as an additional 
source of service information for accomplishing the replacement 
required by this AD.

Alternative Methods of Compliance

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

Special Flight Permits

    (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.

    Note 4: The subject of this AD is addressed in French 
airworthiness directive 1999-435-296(B), dated November 3, 1999.


    Issued in Renton, Washington, on April 13, 2000.
Charles D. Huber,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-9822 Filed 4-18-00; 8:45 am]
BILLING CODE 4910-13-U