[Federal Register Volume 62, Number 229 (Friday, November 28, 1997)]
[Proposed Rules]
[Pages 63296-63298]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-31158]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-188-AD]
RIN 2120-AA64
Airworthiness Directives; Airbus Model A300, A310, and 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, A310, and
A300-600 series airplanes. For certain airplanes, this proposal would
require replacing the bearings of the throttle control levers with new
sealed bearings. For certain other airplanes, this proposal would
require replacing the throttle control assemblies with new assemblies.
This proposal is prompted by the issuance of mandatory continuing
airworthiness information by a foreign civil airworthiness authority.
The actions specified by the proposed AD are intended to prevent
asymmetric engine thrust on the airplane when the autothrottle is
engaged, which could result in roll and yaw disturbances, and
consequent reduced controllability of the airplane.
DATES: Comments must be received by December 29, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-188-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: International Branch, ANM-116, FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington 98055-4556, 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 97-NM-188-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. 97-NM-188-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
[[Page 63297]]
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 all Airbus Model A300, A310, and A300-600 series
airplanes. The DGAC advises that it received reports indicating that
the throttle control levers were difficult to move. This excessive
friction or seizure of throttle control levers has been attributed to
lack of lubrication and dust contamination of the bearings. In the case
of airplanes equipped with full authority digital engine control
(FADEC), this condition can also be attributed to excessive roller
wear. These conditions could lead to asymmetric throttle movements and
engine thrust when the autothrottle is engaged. Such asymmetric
movements, if not corrected, could result in roll and yaw disturbances,
and consequent reduced controllability of the airplane.
Explanation of Relevant Service Information
Airbus has issued Service Bulletin A300-76-0018, dated October 12,
1995, as revised by Change Notice O.A., dated February 18, 1997 (for
Model A300 series airplanes); and Service Bulletin A300-76-6010, dated
October 12, 1995, as revised by Change Notice O.A., dated February 18,
1997 (for Model A300-600 series airplanes); and Service Bulletin A310-
76-2013, dated October 12, 1995, as revised by Change Notice O.A.,
dated February 18, 1997 (for Model A310 series airplanes). These
service bulletins describe procedures for replacement of the four
bearings located on both throttle control levers with new sealed
bearings. Replacement of these bearings will ensure a smooth and
consistent operation of both throttles.
Airbus also has issued Service Bulletin A310-76-2014, Revision 2,
dated January 6, 1997 (for Model A310 series airplanes); and Service
Bulletin A300-76-6011, Revision 2, dated January 6, 1997 (for Model
A300-600 series airplanes). These service bulletins describe procedures
for replacement of two throttle control assemblies equipped with
rollers with new throttle control assemblies equipped with bearings.
Accomplishment of the actions specified in the service bulletins is
intended to adequately address the identified unsafe condition.
The DGAC classified these service bulletins as mandatory and issued
French airworthiness directive (C/N) 96-270-209 (B), dated November 20,
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 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.
Cost Impact
The FAA estimates that 66 airplanes of U.S. registry would be
affected by this proposed AD.
The FAA estimates that the proposed replacement of the bearings
would be required to be accomplished on 57 airplanes. It would take
approximately 24 work hours per airplane to accomplish that action, at
an average labor rate of $60 per work hour. Required parts would be
provided by the manufacturer at no cost to the operators. Based on
these figures, the cost impact of the replacement of the bearings
proposed by this AD on U.S. operators is estimated to be $82,080, or
$1,440 per airplane.
The FAA estimates that the proposed replacement of the throttle
support assemblies would be required to be accomplished on 9 airplanes.
It would take approximately 28 work hours per airplane to accomplish
that action, at an average labor rate of $60 per work hour. Required
parts would cost approximately $1,138 per airplane. Based on these
figures, the cost impact of the replacement of the throttle support
assemblies proposed by this AD on U.S. operators is estimated to be
$25,362, or $2,818 per airplane.
The cost impact figures discussed above are 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 ``Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-188-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.''
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 97-NM-188-AD.
Applicability: All Model A300, A310, and A300-600 series
airplanes, certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding
[[Page 63298]]
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 (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 asymmetric engine thrust on the airplane when the
autothrottle is engaged, which could result in roll and yaw
disturbances, and consequent reduced controllability of the
airplane, accomplish the following:
(a) Within 18 months or 3,500 flight hours after the effective
date of this AD, whichever occurs first, accomplish paragraph (a)(1)
or (a)(2) of this AD, as applicable.
(1) For Model A300, A300-600, and A310 series airplanes: Replace
the four bearings located on both throttle control levers with new
sealed bearings, in accordance with Airbus Service Bulletin A300-76-
0018, dated October 12, 1995, as revised by Airbus Service Bulletin
Change Notice O.A., dated February 18, 1997 (for Model A300 series
airplanes); Airbus Service Bulletin A300-76-6010, dated October 12,
1995, as revised by Airbus Service Bulletin Change Notice O.A, dated
February 18, 1997 (for Model A300-600 series airplanes); or Airbus
Service Bulletin A310-76-2013, dated October 12, 1995, as revised by
Airbus Service Bulletin Change Notice O.A., dated February 18, 1997;
as applicable.
(2) For Model A310 and A300-600 series airplanes equipped with
full authority digital engine control (FADEC): Replace the two
throttle support assemblies equipped with rollers with new throttle
support assemblies equipped with bearings, in accordance with Airbus
Service Bulletin A310-76-2014, Revision 2, dated January 6, 1997
(for Model A310 series airplanes); or Airbus Service Bulletin A300-
76-6011, Revision 2, dated January 6, 1997 (for Model A300-600
series airplanes); as applicable.
Note 2: Replacements accomplished prior to the effective date of
this AD in accordance with Airbus Service Bulletin A310-76-2014,
Revision 1, dated March 25, 1996; or Airbus Service Bulletin A300-
76-6011, Revision 1, dated March 25, 1996; are considered acceptable
for compliance with the applicable action specified in paragraph
(a)(2) of this AD.
(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 International Branch, ANM-116.
(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 96-270-209 (B), dated November 20, 1996.
Issued in Renton, Washington, on November 20, 1997.
Stewart R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-31158 Filed 11-26-97; 8:45 am]
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