[Federal Register Volume 63, Number 156 (Thursday, August 13, 1998)]
[Proposed Rules]
[Pages 43349-43351]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-21715]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-187-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 supersedure of an existing 
airworthiness directive (AD), applicable to all Airbus Model A300, 
A310, and A300-600 series airplanes, that currently requires performing 
a ram air turbine (RAT) extension test; removing and disassembling the 
RAT uplock mechanism; performing an inspection to detect corrosion of 
the RAT uplock mechanism, and replacement with a new assembly, if 
necessary; and cleaning all the parts of the RAT control shaft and its 
bearing component parts. This action would require modification of the 
RAT unlocking control unit, which would constitute terminating action 
for the repetitive tests and inspections. This action also would limit 
the applicability of the existing AD. 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 prevent corrosion of the RAT uplock pin/shaft and 
needle, which could result in failure of the RAT to deploy and 
consequent loss of emergency hydraulic power to the flight controls in 
the event that power is lost in both engines.

DATES: Comments must be received by September 14, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-187-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 98-NM-187-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.

[[Page 43350]]

98-NM-187-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

    On October 20, 1997, the FAA issued AD 97-22-06, amendment 39-10177 
(62 FR 55726, October 28, 1997), applicable to all Airbus Model A300, 
A310, and A300-600 airplanes, to require performing a ram air turbine 
(RAT) extension test; removing and disassembling the RAT uplock 
mechanism; performing an inspection to detect corrosion of the RAT 
uplock mechanism, and replacement with a new assembly, if necessary; 
and cleaning all the parts of the RAT control shaft and its bearing 
component parts. That action was prompted by reports indicating that 
the RAT did not extend during ground testing, due to corrosion in the 
uplock pin/shaft and the needle bearing of the RAT. The requirements of 
that AD are intended to detect and correct such corrosion of the RAT, 
which could result in failure of the RAT to deploy and consequent loss 
of emergency hydraulic power to the flight controls in the event that 
power is lost in both engines.

Issuance of New Service Information

    The manufacturer has issued Airbus Service Bulletins A300-29-0109 
(for Model A300 series airplanes); A310-29-2077 (for Model A310 series 
airplanes); and A300-29-6038 (for Model A300-600 series airplanes); all 
dated January 27, 1997; which describe procedures for modification of 
the RAT unlocking control unit, which would eliminate the need for the 
repetitive tests and inspections. In addition, the service bulletins 
limit the effectivity to those airplanes on which the modification was 
not accomplished during production. Accomplishment of the actions 
specified in the service bulletins is intended to adequately address 
the identified unsafe condition. The Direction Generale de l'Aviation 
Civile (DGAC) approved these service bulletins as optional terminating 
action, and issued French airworthiness directive 95-163-182(B)R3, 
dated May 7, 1997, 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 supersede AD 97-22-06 to 
continue to require performing a RAT extension test; removing and 
disassembling the RAT uplock mechanism; performing an inspection to 
detect corrosion of the RAT uplock mechanism, and replacement with a 
new assembly, if necessary; and cleaning all the parts of the RAT 
control shaft and its bearing component parts. The proposed AD would 
add a requirement to modify the RAT unlocking control unit, which would 
constitute terminating action for the repetitive test and inspection 
requirements. The proposed AD also would limit the applicability of the 
existing AD to those airplanes on which the modification was not 
accomplished during production. The actions would be required to be 
accomplished in accordance with the service bulletins described 
previously.

Differences Between Proposed Rule and Foreign AD

    The proposed AD would differ from the parallel French airworthiness 
directive in that it would mandate the accomplishment of the 
terminating action for the repetitive tests and inspections. The French 
airworthiness directive provides for that action as optional.
    Mandating the terminating action is based on the FAA's 
determination that long-term continued operational safety will be 
better assured by modifications or design changes to remove the source 
of the problem, rather than by repetitive inspections. Long-term tests 
and inspections may not be providing the degree of safety assurance 
necessary for the transport airplane fleet. This, coupled with a better 
understanding of the human factors associated with numerous continual 
inspections, has led the FAA to consider placing less emphasis on 
inspections and more emphasis on design improvements. The proposed 
modification requirement is in consonance with these conditions.

Cost Impact

    There are approximately 126 Model A300, A310, and A300-600 series 
airplanes of U.S. registry that would be affected by this proposed AD.
    The actions that are currently required by AD 97-22-06 take 
approximately 10 work hours per airplane to accomplish, 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 currently required actions on U.S. operators is 
estimated to be $75,600, or $600 per airplane.
    The modification that is proposed in this AD action would take 
approximately 9 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Required parts would cost 
approximately $1,972 per airplane. Based on these figures, the cost 
impact of the modification proposed by this AD on U.S. operators is 
estimated to be $316,512, or $2,512 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or 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 ``ADDRESSES.''

[[Page 43351]]

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 removing amendment 39-10177 (62 FR 
55726, October 28, 1997), and by adding a new airworthiness directive 
(AD), to read as follows:

Airbus Industrie: Docket 98-NM-187-AD. Supersedes AD 97-22-06, 
Amendment 39-10177.
    Applicability: Model A300, A310, and A300-600 series airplanes 
on which Airbus Modification 11527 has not 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 (d) 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 corrosion of the ram air turbine (RAT) uplock pin/
shaft and needle, which could result in failure of the RAT to deploy 
and consequent loss of emergency hydraulic power to the flight 
controls in the event that power is lost in both engines, accomplish 
the following:

Restatement of the Requirements of AD 97-22-06

    (a) Within 30 months since the date of manufacture, or within 3 
months after December 2, 1997 (the effective date of AD 97-22-06, 
amendment 39-10177), whichever occurs later: Accomplish the 
requirements of paragraphs (a)(1) and (a)(2) of this AD in 
accordance with Airbus Service Bulletin A300-29-0108, dated April 1, 
1996 (for Model A300 series airplanes); A310-29-2076, dated April 1, 
1996 (for Model A310 series airplanes); or A300-29-6037, dated April 
1, 1996 (for Model A300-600 series airplanes); as applicable. 
Thereafter, repeat these actions at intervals not to exceed 30 
months.
    (1) Perform a RAT extension test on the ground, in accordance 
with the procedures specified in the Maintenance Manual.
    (2) Disassemble and remove the uplock mechanism of the RAT and 
perform a visual inspection of the uplock mechanism to detect 
corrosion, in accordance with the applicable service bulletin.

    Note 2: For the purposes of this AD, the RAT uplock mechanism 
includes both the lever assembly and uplock unit.

    (i) If no corrosion is detected: Prior to further flight, clean and 
lubricate the uplock mechanism and its associated parts, reinstall the 
assembly, and perform a retraction/extension/retraction of the RAT, in 
accordance with the applicable service bulletin.
    (ii) If any corrosion is detected in any part of the uplock 
mechanism, prior to further flight, accomplish either paragraph 
(a)(2)(ii)(A) or (a)(2)(ii)(B) of this AD in accordance with the 
applicable service bulletin.
    (A) Replace the uplock mechanism with a new part and perform a 
retraction/extension/retraction of the RAT, in accordance with the 
applicable service bulletin. Or
    (B) Clean and lubricate the uplock mechanism and its associated 
parts. Within 30 days following accomplishment of this cleaning and 
lubrication, replace the uplock mechanism with a new part and 
perform a retraction/extension/retraction of the RAT.
    (b) Initial accomplishment of the actions required by paragraph 
(a) of this AD that have been performed in accordance with Airbus 
All Operator Telex 29-16, Revision 01, dated January 10, 1996, is 
considered acceptable for compliance with the initial RAT extension 
test and an initial visual inspection as required by paragraph (a) 
of this AD. However, the first repetitive inspection, as required by 
paragraph (a) of this AD, must be performed within 30 months after 
that RAT extension test and visual inspection were conducted, and 
repeated thereafter at intervals not to exceed 30 months.

New Requirements of this AD

    (c) Within 30 months after the effective date of this AD, modify 
the RAT unlocking control unit in accordance with Airbus Service 
Bulletin A300-29-0109 (for Model A300 series airplanes); A310-29-
2077 (for Model A310 series airplanes); or A300-29-6038 (for Model 
A300-600 series airplanes); all dated January 27, 1997; as 
applicable. Accomplishment of this modification constitutes 
terminating action for the repetitive test and inspection 
requirements of this AD.
    (d) 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.

    (e) 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 95-163-182(B)R3, dated May 7, 1997.

    Issued in Renton, Washington, on August 7, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-21715 Filed 8-12-98; 8:45 am]
BILLING CODE CODE 4910-13-P