[Federal Register Volume 64, Number 178 (Wednesday, September 15, 1999)]
[Proposed Rules]
[Pages 50023-50026]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-24090]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-31-AD]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Model BAC 1-11 200 
and 400 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.


[[Page 50024]]


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 British Aerospace Model BAC 1-
11 200 and 400 series airplanes. This proposal would require replacing 
the thrust reverser control unit selector valve with a new or modified 
valve and inspecting for proper rigging of the thrust reverser cable 
drums and thrust reverser control unit selector valve detent, and 
corrective actions, if necessary. This proposal also would require 
revising the Airplane Flight Manual to provide the flight crew with 
procedures to address uncontrolled operation of the thrust reverser 
system. 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 provide the 
flight crew with procedures in the event of uncommanded deployment of 
the thrust reverser, and to prevent uncommanded deployment of the 
thrust reverser in flight or on the ground, which could result in 
reduced controllability of the airplane.

DATES: Comments must be received by October 15, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-31-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9 a.m. and 3 p.m., Monday through Friday, except Federal 
holidays.
    The service information referenced in the proposed rule may be 
obtained from British Aerospace, Service Support, Airbus Limited, P.O. 
Box 77, Bristol BS99 7AR, England. 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 99-NM-31-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. 99-NM-31-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, notified the FAA that an unsafe 
condition may exist on all British Aerospace Model BAC 1-11 200 and 400 
series airplanes. The CAA advises that two uncommanded thrust reverser 
deployments on the ground have been reported. The cause of the 
deployments was control cable failure. The control cable in both 
incidents had been incorrectly routed over a guard pin and had worn 
through. Also, during investigations of the thrust reverser rigging, 
instances have been found where the thrust reverser selector valve 
detent was not rigged properly and was not in the forward idle 
position. Misrigging of the thrust reverser control pulleys or the 
thrust reverser selector valve detent could result in uncommanded 
deployment of the thrust reverser in flight or on the ground, which 
could result in reduced controllability of the airplane.

Explanation of Relevant Service Information

    British Aerospace has issued Alert Service Bulletin 76-A-PM6043, 
Issue No. 1, dated September 18, 1998, which describes procedures for 
inspecting the thrust reverser cable drums and pulleys for proper 
rigging, and adjustment, if necessary.
    British Aerospace also has issued Service Bulletin 78-PM6047, Issue 
No. 1, dated November 27, 1998, which describes procedures for 
replacing the thrust reverser control unit selector valve with a new or 
modified selector valve.
    British Aerospace also has issued BAC 1-11 Airplane Flight Manual 
(AFM) Advance Amendment Bulletins No. 12 and No. 16, both dated August 
19, 1997, which describe procedures for revising the Emergency and 
Abnormal Procedure Sections of the British Aerospace BAC 1-11 AFM to 
provide the flight crew with procedures in the event of thrust reverser 
uncommanded deployment in flight and when the thrust reverser is 
indicated to be in the unlocked position during flight.
    Rolls-Royce Spey Aero Engine has issued Service Bulletin Sp78-131, 
dated September 1998, which describes procedures for inspecting the 
thrust reverser control unit selector valve detent for proper rigging, 
and adjustment, if necessary.
    Accomplishment of the actions specified in the service bulletins 
and advance amendment bulletins is intended to adequately address the 
identified unsafe condition. The CAA classified these service bulletins 
as mandatory and issued British airworthiness directives 002-09-08 and 
005-11-98 in order to assure the continued airworthiness of these 
airplanes in the United Kingdom.

FAA's Conclusions

    This airplane model is manufactured in the United Kingdom 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 CAA has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the CAA, 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.

[[Page 50025]]

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 and advance amendment 
bulletins described previously.

Differences Between Proposed Rule and the Foreign Airworthiness 
Directive

    The proposed AD would differ from the parallel British 
airworthiness directives in that it would require incorporation of BAC-
1-11 AFM Advance Amendment Bulletins No. 12 and No. 16 dated August 19, 
1997 into the AFM. The British airworthiness directives do not provide 
for such a requirement. The FAA has determined that, because of the 
safety implications, it is necessary to revise the AFM to provide 
emergency procedures to address uncommanded operation of the thrust 
reverser system.

Cost Impact

    The FAA estimates that 16 airplanes of U.S. registry would be 
affected by this proposed AD.
    It would take approximately 6 work hours per airplane to accomplish 
the proposed inspections, and at average labor rate of $60 per work 
hour. Based on these figures, the cost impact of the inspections 
proposed by this AD on U.S. operators is estimated to be $5,760, or 
$360 per airplane.
    It would take approximately 1 work hour per airplane to accomplish 
the proposed replacement, and an average labor rate of $60 per work 
hour. Required parts would cost approximately $16,000 per airplane. 
Based on these figures, the cost impact of the replacement proposed by 
this AD on U.S. operators is estimated to be $256,960, or $16,060 per 
airplane.
    It would take approximately 1 work hour per airplane to accomplish 
the proposed AFM revision, and at average labor rate of $60 per work 
hour. Based on these figures, the cost impact of the inspection 
proposed by this AD on U.S. operators is estimated to be $960, or $60 
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 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:

British Aerospace Airbus Limited (Formerly British Aerospace 
Commercial Aircraft Limited, British Aerospace Aircraft Group): 
Docket 99-NM-31-AD.

    Applicability: All Model BAC 1-11 200 and 400 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 (e) 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 provide the flight crew with procedures in the event of 
uncommanded deployment of the thrust reverser and to prevent 
uncommanded deployment of the thrust reverser in flight or on the 
ground, which could result in reduced controllability of the 
airplane, accomplish the following:
    (a) Within 30 days after the effective date of this AD, perform 
an inspection for proper rigging of the thrust reverser cable drums, 
in accordance with British Aerospace Alert Service Bulletin 76-A-
PM6043, Issue No. 1, dated September 18, 1998. If any drum is found 
to be improperly rigged, prior to further flight, accomplish the 
adjustments specified in paragraph 3, ``Adjustments,'' of the 
service bulletin.
    (b) Prior to further flight after accomplishing the inspection 
required by paragraph (a) of this AD, perform an inspection for 
proper rigging of the thrust reverser selector valve detent, in 
accordance with Rolls-Royce Spey Service Bulletin Sp78-131, dated 
September 1998. If any discrepancy is found, prior to further 
flight, accomplish the adjustments specified in paragraph 3, 
``Adjustments,'' of the service bulletin.
    (c) Within 30 days after the effective date of this AD, revise 
the Emergency and Abnormal Procedures Sections of the FAA-approved 
Airplane Flight Manual (AFM) by inserting British Aerospace Advance 
Amendment Bulletins No. 12 and No. 16, both dated August 19, 1997, 
into the applicable sections of the AFM.
    (d) Within 12 months after the effective date of this AD, 
replace the thrust reverser control unit selector valve with a new 
or modified selector valve in accordance with British Aerospace 
Service Bulletin 78-PM6047, Revision 1, dated November 27, 1998.

Alternative Methods of Compliance

    (e) 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 who may 
add comments and then send it to the Manager, International Branch, 
ANM-116.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (f) Special flight permits may be issued in accordance with 
Secs.  21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197

[[Page 50026]]

and 21.199) to operate the airplane to a location where the 
requirements of this AD can be accomplished.

    Note 3: The subject of this AD is addressed in British 
airworthiness directives 002-09-98 and 005-11-98.

    Issued in Renton, Washington, on September 9, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-24090 Filed 9-14-99; 8:45 am]
BILLING CODE 4910-13-U