[Federal Register Volume 59, Number 31 (Tuesday, February 15, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-3286]


[[Page Unknown]]

[Federal Register: February 15, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-10-AD; Amendment 39-8823; AD 94-04-05]

 

Airworthiness Directives; Airbus Industrie Models A300, A310, and 
A300-600 Series Airplanes Equipped With Dowty Ram Air Turbines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain Airbus Industrie Models A300, A310, and A300-
600 series airplanes. This action requires repetitive deployment tests 
of the ram air turbine (RAT) and checks of the adjustment of the 
locking rod. This amendment is prompted by reports of failure of the 
RAT to rotate when necessary, due to maladjustment of the locking rod. 
The actions specified in this AD are intended to ensure the 
availability of the RAT in case of need.

DATES: Effective March 2, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 2, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before April 18, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-10-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The service information referenced in this AD 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; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Stephen Slotte, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206) 
227-2797; fax (206) 227-1320.

SUPPLEMENTARY INFORMATION: 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 Airbus Models 
A300, A310, and A300-600 series airplanes equipped with certain Dowty 
ram air turbines (RAT). The DGAC advises that there has been a report 
of a RAT failing to rotate during an in-flight deployment test. The 
locking rod did not move sufficiently to release the turbine and, 
consequently, no rotation of the spinner was possible. Initial 
investigations revealed that this situation was caused by a combination 
of: (1) Corrosion inside of the spring housing located at the upper 
part of the leg, where the upper part of the locking rod goes through; 
and (2) probable maladjustment of the locking rod itself. Further 
investigation revealed that the lubricating grease in this area had 
decomposed into solid particles, and the resulting friction appeared 
high enough to contribute to the stiff movement of the locking rod 
assembly. This condition, if not corrected, could result in the 
unavailability of the RAT in case of need.
    In response to this situation, Airbus Industrie issued an All 
Operator Telex (AOT) in July 1993, recommending that operators perform 
repetitive ground extension tests of the RAT to ensure that it was in 
proper working condition, and repetitive checks of the locking rod for 
proper movement. That AOT instructed operators to adjust the locking 
rod at 5 to 10 degrees from full travel of the leg extended position. 
(By adjusting to that point, alignment with the surface of the lock 
plate was expected to be reached.) The AOT also recommended that 
operators apply additional lubricating grease at the top and bottom of 
the spring housing, so that the area would be sealed against moisture 
and corrosion would be inhibited.
    Subsequent to the issuance of that AOT, a report was received 
indicating that, during an in-flight deployment test on a Model A300 
series airplane, one of the blades of the RAT was damaged. 
Investigation of this incident revealed that the RAT locking rod had 
been adjusted to 10 degrees from full travel of the leg in extended 
position, as was recommended in the previously-issued AOT. 
Consequently, this had allowed the RAT blades to start to rotate too 
early and contact the RAT door. Potential contact between the RAT 
blades and RAT doors is not readily detectable during a normal RAT 
ground functional test, since the RAT does not rotate during the 
extension phase of the test. If this latent failure occurs, it can lead 
to damage of the RAT blades and subsequent reduced performance of the 
RAT during times when its use is needed.
    In order to address this situation, Airbus Industrie issued All 
Operator Telex 29-09, dated November 16, 1993, which recommends similar 
inspection, adjustment, and lubrication actions to those called for in 
the previous AOT, but reduces the tolerances for adjustment of the RAT 
locking rod to 5 (+0.5 to -1.0) degrees. This reduction of the 
adjustment tolerances will prevent the previously described situation 
from occurring and thereby preclude the problems associated with the 
RAT blades rotating too early. The DGAC classified this service 
bulletin as mandatory and issued French Airworthiness Directive 93-136-
146(B)R1, dated December 22, 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 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, this AD is being issued to prevent reduced 
performance of the RAT in case of need. This AD requires repetitive 
ground extension test of the RAT to ensure that it is in proper working 
condition, and repetitive checks of the locking rod for proper movement 
and adjustment, if necessary. This AD also requires application of 
additional lubricating grease at the top and bottom of the spring 
housing. The actions are required to be accomplished in accordance with 
Airbus AOT 29-09, described previously.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ``addresses.'' 
All communications received on or before the closing date for comments 
will be considered, and this rule may be amended in light of the 
comments received. Factual information that supports the commenter's 
ideas and suggestions is extremely helpful in evaluating the 
effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD 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 94-NM-10-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and is not a ``significant regulatory action'' 
under Executive Order 12866. It has been determined further that this 
action involves an emergency regulation under DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979). If it is determined 
that this emergency regulation otherwise would be significant under DOT 
Regulatory Policies and Procedures, a final regulatory evaluation will 
be prepared and placed in the Rules Docket. A copy of it, if filed, may 
be obtained from the Rules Docket at the location provided under the 
caption ``ADDRESSES.''

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 14 CFR part 
39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:


    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

94-04-05 Airbus: Amendment 39-8823. Docket 94-NM-10-AD.

    Applicability: Models A300, A310, and A300-600 series airplanes, 
certificated in any category; equipped with the following Dowty ram 
air turbines (RAT), part numbers:

RAT 16C 100 VG
RAT 16C 101 VG
RAT 16C 102 VG
RAT 16C 103 VG
RAT 16C 104 VG
RAT 16C 105 VG
RAT 16C 109 VG
RAT 16C 110 VG
RAT 16C 116 VG
RAT 16C 117 VG

    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure the availability of the ram air turbine (RAT) in case 
of need, accomplish the following:
    (a) Within 60 days after the effective date of this AD, or prior 
to accumulation of 500 hours time-in-service after the effective 
date of this AD, whichever occurs first, perform a deployment test 
of the RAT and check the adjustment of the locking rod, in 
accordance with Airbus All Operator Telex (AOT) 29-09, dated 
November 16, 1993. Repeat the deployment test and adjustment check 
thereafter at intervals not to exceed 10 months.
    (1) If no discrepancy is found, prior to further flight, apply 
grease to the RAT leg at the entry and exit positions of the locking 
rod spring housing, in accordance with the AOT.
    (2) If any discrepancy is found, prior to further flight correct 
it and apply grease to the RAT leg at the entry and exit positions 
of the locking rod spring housing, in accordance with the AOT.
    (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: 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 
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
airplane to a location where the requirements of this AD can be 
accomplished.
    (d) The actions shall be done in accordance with Airbus All 
Operator Telex (AOT) 29-09, dated November 16, 1993. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 
51. Copies may be obtained from Airbus Industrie, 1 Rond Point 
Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (e) This amendment becomes effective on March 17, 1994.

    Issued in Renton, Washington, on February 7, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-3286 Filed 2-14-94; 8:45 am]
BILLING CODE 4910-13-U