[Federal Register Volume 60, Number 75 (Wednesday, April 19, 1995)]
[Proposed Rules]
[Pages 19549-19551]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-9624]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-166-AD]


Airworthiness Directives; British Aerospace Model Viscount 744, 
745D, and 810 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 British Aerospace Model 
Viscount 744, 754D, and 810 airplanes. This proposal would require an 
inspection to detect corrosion of the tailplane assemblies, and 
correction of discrepancies. This proposal is prompted by a report of 
corrosion on the main spar top and bottom forward boom of the tailplane 
assemblies and reports of cracking in the upper root joint attachment 
fitting. The actions specified by the proposed AD are intended to 
prevent such cracking or corrosion of the main spar forward booms or 
the upper root joint attachment fitting, which consequently 
[[Page 19550]] could lead to the failure of the tailplane assemblies; 
this condition could result in reduced controllability of the airplane.

DATES: Comments must be received by May 30, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-166-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 94-NM-166-AD. This information may be examined at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: William Schroeder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206) 
227-2148; fax (206) 227-1320.

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 94-NM-166-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. 94-NM-166-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority, which is the airworthiness authority 
for the United Kingdom, recently notified the FAA that an unsafe 
condition may exist on all British Aerospace Model Viscount 744, 754D, 
and 810 airplanes. The CAA advises that it has received a report of 
corrosion on the main spar top and bottom forward boom of the tailplane 
assemblies. Several incidents of cracking have also been discovered in 
the upper root joint attachment fitting. The effects of such cracking 
or corrosion could lead to the failure of the main spar forward booms 
or the upper root joint attachment fitting, which consequently could 
lead to the failure of the tailplane assemblies. This condition, if not 
corrected, could result in reduced controllability of the airplane.
    British Aerospace has issued Viscount Alert Preliminary Technical 
Leaflet (PTL) 182, Issue 2, dated August 7, 1992 (for Model Viscount 
810 airplanes); and Viscount PTL 313, Issue 2, dated February 1, 1993 
(for Model Viscount 744, 754D, airplanes), which describe procedures 
for performing an inspection to detect corrosion of the tailplane 
assemblies, and correction of discrepancies. The CAA classified these 
PTL's as mandatory.
    These airplane models are manufactured in the United Kingdom 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 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.
    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 an inspection to 
detect corrosion of the tailplane assemblies, and correction of 
discrepancies. The actions would be required to be accomplished in 
accordance with the PTL's described previously.
    The FAA estimates that 29 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 160 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
total cost impact of the proposed AD on U.S. operators is estimated to 
be $278,400, or $9,600 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:

    [[Page 19551]] 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:

British Aerospace Regional Aircraft Limited (Formerly British 
Aerospace Commercial Aircraft Limited, Vickers-Armstrongs Aircraft 
Limited): Docket 94-NM-166-AD.

    Applicability: All Model Viscount 744, 754D, and 810 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 use the authority 
provided in paragraph (b) 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 cracking or corrosion of the main spar forward booms 
or the upper root joint attachment fitting, which consequently could 
lead to the failure of the tailplane assemblies and reduce the 
controllability of the airplane, accomplish the following:
    (a) Prior to the accumulation of 8 years of service since date 
of manufacture of this airplane, or within 18 months after the 
effective date of this AD, whichever occurs later, perform an 
inspection to detect corrosion of the tailplane assemblies, in 
accordance with British Aerospace Regional Aircraft Limited Viscount 
Alert Preliminary Technical Leaflet (PTL) 182, Issue 2, dated August 
7, 1992 (for Model Viscount 810 airplanes), or Viscount PTL 313, 
Issue 2, dated February 1, 1993 (for Model Viscount 744, 754D, 
airplanes), as applicable. If corrosion is detected during the 
inspection, prior to further flight, correct the discrepancies in 
accordance with the service bulletin. Thereafter, repeat the 
inspection at intervals not to exceed 8 years.
    (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 April 13, 1995.
John J. Hickey,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-9624 Filed 4-18-95; 8:45 am]
BILLING CODE 4910-13-U