[Federal Register Volume 60, Number 141 (Monday, July 24, 1995)]
[Rules and Regulations]
[Pages 37817-37818]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-17032]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-112-AD; Amendment 39-9305; AD 95-15-02]


Airworthiness Directives; British Aerospace Model Viscount 744, 
745D, and 810 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all British Aerospace Model Viscount 744, 745D, and 810 
airplanes, that requires an inspection of fittings of the engine mount 
structure to determine whether fasteners have been installed in 
inspection holes and to determine whether those holes are oversized. It 
also requires various follow-on actions, depending upon the results of 
the inspection. This amendment is prompted by reports indicating that 
fasteners were installed in the inspection hole of the engine ``W'' 
frame socket fittings and the inspection hole was oversized due to 
fatigue cracking. The actions specified by this AD are intended to 
prevent such fatigue cracking, which could lead to failure of the 
fasteners and consequent separation of the engine from the airframe.

DATES: Effective August 23, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 23, 1995.

ADDRESSES: The service information referenced in this AD may be 
obtained from British Aerospace Regional Aircraft Ltd., Engineering 
Support Manager, Military Business Unit, Chadderton Works, Greengate, 
Middleton, Manchester M24 1SA, England. This information may be 
examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 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: 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) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to all British Aerospace Model 
Viscount 744, 745D, and 810 airplanes was published in the Federal 
Register on April 19, 1995 (60 FR 19551). That action proposed to 
require performing a detailed visual inspection of ``W'' frame socket 
fittings of the engine mount structure to determine whether drive 
screws or blind rivets have been installed in inspection holes and to 
determine whether those holes are oversized. It also proposed to 
require various follow-on actions, depending upon the results of the 
inspection.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public. 
The FAA has determined that air safety and the public interest require 
the adoption of the rule as proposed.
    The FAA estimates that 29 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 25 work hours per 
airplane to accomplish the required actions, and that the average labor 
rate is $60 per work hour. Based on these figures, the total cost 
impact of the AD on U.S. operators is estimated to be $43,500, or 
$1,500 per airplane.
    The total cost impact figure discussed above is based on 
assumptions that no operator has yet accomplished any of the 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.
    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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) will not have a 
significant economic 

[[Page 37818]]
impact, positive or negative, on a substantial number of small entities 
under the criteria of the Regulatory Flexibility Act. A final 
evaluation has been prepared for this action and it is contained in the 
Rules Docket. A copy of it 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 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. 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:

95-15-02 British Aerospace Regional Aircraft Limited (Formerly 
British Aerospace Commercial Aircraft Limited, Vickers-Armstrongs 
Aircraft Limited): Amendment 39-9305. Docket 94-NM-112-AD.

    Applicability: All Model Viscount 744, 745D, 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 (c) of this AD 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 fatigue cracking, which could lead to the possible 
separation of the engine from the airframe, accomplish the 
following:
    (a) Within 12 months after the effective date of this AD, 
perform a detailed visual inspection of ``W'' frame socket fittings 
of the engine mount structure to determine whether drive screws or 
blind rivets have been installed in inspection holes and to 
determine whether those holes are oversized, in accordance with the 
Accomplishment Instructions, section 2.1 PART ONE, paragraphs A., 
B., C., D., E., and F., of British Aerospace Preliminary Technical 
Leaflet (PTL) 501, dated May 1, 1994.
    (b) If drive screws or blind rivets are found installed, or if 
the inspection holes are found to be oversized, during the 
inspection required by paragraph (a) of this AD, at the next 
scheduled engine removal, but no later than 12 months after the 
effective date of this AD, perform a nondestructive test (NDT) to 
detect discontinuities (i.e., cracks, corrosion, and mechanical 
damage) at inspection holes; rework the hole or replace the ``W'' 
frame fitting with a new or serviceable part; and perform the 
specified follow-on actions; in accordance with the Accomplishment 
Instructions, section 2.2 PART TWO, paragraphs A., B., C., D., E., 
and F., of British Aerospace Preliminary Technical Leaflet (PTL) 
501, dated May 1, 1994.
    (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.
    (e) The inspection and test shall be done in accordance with 
British Aerospace Preliminary Technical Leaflet (PTL) 501, dated May 
1, 1994, which contains the following list of effective pages:

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                                   Revision level shown   Date shown on 
             Page No.                     on page              page     
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1-9..............................  Original............  May 1, 1994.   
                                                                        
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                               Appendix 1                               
                                                                        
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1-6..............................  Original............  January 1,     
                                                          1994.         
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    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 British Aerospace Regional 
Aircraft Ltd., Engineering Support Manager, Military Business Unit, 
Chadderton Works, Greengate, Middleton, Manchester M24 1SA, England. 
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.
    (f) This amendment becomes effective on August 23, 1995.

    Issued in Renton, Washington, on July 6, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-17032 Filed 7-21-95; 8:45 am]
BILLING CODE 4910-13-U