[Federal Register Volume 60, Number 203 (Friday, October 20, 1995)]
[Proposed Rules]
[Pages 54202-54203]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-25988]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 60, No. 203 / Friday, October 20, 1995 /
Proposed Rules
[[Page 54202]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-NM-77-AD]
Airworthiness Directives; Airbus Model A320 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 A320 series
airplanes. This proposal would require replacement of the relays in the
forward electronics rack of the braking system of the landing gear with
new relays. This proposal is prompted by reports of loss of the systems
of the braking/steering control unit (BSCU) on these airplanes due to
electrical overvoltage of the relays. The actions specified by the
proposed AD are intended to prevent such electrical overvoltage of the
relays, which could result in the loss of the BSCU systems, and
subsequent loss of the antiskid functions and nose wheel steering of
the airplane.
DATES: Comments must be received by December 4, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-77-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: Charles D. Huber, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206)
227-2589; 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 95-NM-77-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. 95-NM-77-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 certain Airbus Model A320 series
airplanes. The DGAC advises that it has received several reports of
loss of the two systems of the braking/steering control unit (BSCU) on
these airplanes. Investigation revealed that this problem was caused by
an electrical overvoltage of the relays during the transfer to the
second system of the BSCU upon the loss of the first system. This
condition, if not corrected, could result in loss of the BSCU system,
and subsequent loss of the antiskid functions and nose wheel steering
of the airplane.
Airbus has issued Service Bulletin A320-32-1115, Revision 2, dated
September 21, 1994, which describes procedures for replacement of the
relays 24 GG and 25 GG in the forward electronics rack 90VU of zone 120
of the braking system of the landing gear with new relays. This
replacement will improve the electrical overvoltage protection on the
braking system. The DGAC classified this service bulletin as mandatory
and issued French airworthiness directive (CN) 93-163-043 (B), dated
September 29, 1993, in order to assure the continued airworthiness of
these airplanes in France.
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.
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
certain relays in the forward electronics rack 90VU of the braking
system of the landing gear with new relays. The actions would be
required to be accomplished in accordance with the service bulletin
described previously.
The FAA estimates that 87 airplanes of U.S. registry would be
affected by this proposed AD, that it would take
[[Page 54203]]
approximately 2 work hours per airplane to accomplish the proposed
actions, and that the average labor rate is $60 per work hour. Required
parts would be supplied by the manufacturer at no cost to the
operators. Based on these figures, the total cost impact of the
proposed AD on U.S. operators is estimated to be $10,440, or $120 per
airplane.
The total 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.
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), 40101, 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Airbus Industrie: Docket 95-NM-77-AD.
Applicability: Model A320 series airplanes on which Airbus
Modification 23611 (reference Airbus Service Bulletin A320-32-1115)
has not been installed; 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 use the authority
provided in paragraph (b) of this AD to request approval from the
FAA. This approval may address either no action, if the current
configuration eliminates the unsafe condition; or different actions
necessary to address the unsafe condition described in this AD. Such
a request should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any airplane from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent an electrical overvoltage of the relays, which could
result in the loss of the braking/steering control unit (BSCU)
systems, and subsequent loss of the antiskid functions and nose
wheel steering of the airplane, accomplish the following:
(a) Within 10 months after the effective date of this AD,
replace relays 24 GG and 25 GG in the forward electronics rack 90VU
of zone 120 of the braking system of the landing gear with new
relays, in accordance with Airbus Service Bulletin A320-32-1115,
Revision 2, dated September 21, 1994.
(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,
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,
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 October 16, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-25988 Filed 10-19-95; 8:45 am]
BILLING CODE 4910-13-U
