Airworthiness Directives; Airbus Model A300, A310, and A300-600 Series Airplanes

DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

[Docket No. 96-NM-155-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. This proposal would require performing a ram

air turbine (RAT) extension test; removing and disassembling the RAT

lever assembly; performing an inspection to detect corrosion of the RAT

lever assembly, and replacement with a new assembly, if necessary; and

cleaning all the parts of the RAT control shaft and its bearing

component parts. This proposal is 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 actions

specified by the proposed AD are intended to detect and correct such

corrosion of the RAT, which could result in failure of the RAT to

deploy and subsequent 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 March 31, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-103,

Attention: Rules Docket No. 96-NM-155-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 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

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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-155-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. 96-NM-155-AD, 1601 Lind Avenue, SW., Renton, Washington

98055-4056.

Discussion

The Direction Gonorale 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, A310, and A300-600

series airplanes. The DGAC advises that it has received reports

indicating that the ram air turbine (RAT) did not extend during ground

tests. Investigation revealed that the non-extension of the RAT was due

to corrosion of the RAT control shaft and its bearing needles between

the uplock unit and the lever connected to the control linkage.

Corrosion of the RAT uplock pin/shaft and needle, if not detected and

corrected in a timely manner, could result in failure of the RAT to

deploy and subsequent loss of emergency hydraulic power to the flight

controls in the event that power is lost in both engines.

Explanation of Relevant Service Information

Airbus has issued Service Bulletin A300-29-0108 (for Model A300

series airplanes), Service Bulletin A310-29-2076 (for Model A310 series

airplanes), and Service Bulletin A300-29-6037 (for Model A300-600

series airplanes), all dated dated April 1, 1996, which describe

procedures for the following:

1. Performing a RAT extension test during ground testing;

2. Removing and disassembling the RAT lever assembly (uplock

assembly);

3. Performing a visual inspection to detect corrosion of the RAT

lever assembly; and

4. Cleaning all the parts of the RAT lever assembly and all its

associated parts.

The service bulletins also describe procedures for replacing any

corroded parts with new parts. They also describe procedures for

cleaning and lubricating corroded parts in lieu of replacement with new

parts, in situations where new parts are not readily available.

The DGAC classified these service bulletins as mandatory and issued

French airworthiness directive, 95-163-182(B)R2, dated June 5, 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 a RAT extension

test during ground testing; removal and disassembly of the RAT lever

assembly; a visual inspection to detect corrosion of the RAT lever

assembly, and replacement of the assembly with new parts, if necessary;

and cleaning of the lever assembly and its associated parts. The

actions would be required to be accomplished in accordance with the

service bulletins described previously.

Differences Between Proposed AD and Referenced Service Bulletins

Operators should note that, although the Airbus service bulletins

describe certain cleaning and lubrication procedures of the RAT lever

assembly that can be accomplished in lieu of replacement of corroded

parts, this proposed AD would not permit those actions as an

alternative to replacement. The FAA finds that, to ensure an adequate

level of safety for the affected fleet, corroded parts must be replaced

prior to further flight. The FAA has determined that, in cases where

known unsafe conditions exist and where actions to detect and correct

those unsafe conditions can be readily accomplished, those actions must

be required.

Interim Action

This is considered to be interim action until final action is

identified, at which time the FAA may consider further rulemaking.

Cost Impact

The FAA estimates that 80 Airbus Model A300, A310, and A300-600

series airplanes of U.S. registry would be affected by this proposed

AD, that it would take approximately 10 work hours per airplane to

accomplish the proposed actions, and that the average labor rate is $60

per work hour. Required parts would be provided by the manufacturer at

no cost to the operator. Based on these figures, the cost impact of the

proposed AD on U.S. operators is estimated to be $48,000, or $600 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 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

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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-155-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 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 detect and correct corrosion of the ram air turbine (RAT)

uplock pin/shaft and needle that could result in failure of the RAT

to deploy and subsequent loss of emergency hydraulic power to the

flight controls in the event that power is lost in both engines,

accomplish the following:

(a) Prior to the accumulation of 30 months total time-in-

service, or within 3 months after the effective date of this AD,

whichever occurs later: Accomplish the requirements of paragraphs

(a)(1), (a)(2), (a)(3), and (a)(4) 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); 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 lever assembly of the RAT and

perform a visual inspection of the lever assembly to detect

corrosion, in accordance with the applicable service bulletin.

(i) If no corrosion is detected: Prior to further flight, clean

and lubricate the lever assembly 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 lever

assembly: Prior to further flight, replace the lever assembly with a

new part and perform a retraction/extension/retraction of the RAT,

in accordance with the applicable service bulletin.

(b) Initial accomplishment of the actions required by paragraph

(a) of this AD that have been performed in accordance with Airbus

All Operator Telex (AOT) 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.

(c) 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.

(d) 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 February 11, 1997.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 97-3965 Filed 2-18-97; 8:45 am]

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