[Federal Register Volume 60, Number 2 (Wednesday, January 4, 1995)]
[Rules and Regulations]
[Pages 329-330]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-49]



[[Page 329]]

DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

[Docket No. 94-NM-108-AD; Amendment 39-9109; AD 94-26-14]


Airworthiness Directives; British Aerospace Model Viscount 744, 
745D, and 810 Series 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 
series airplanes, that requires inspections to detect cracks in the 
chassis side bracing structure and in the chassis top strut support 
intercostals inside the wings, and replacement of discrepant parts with 
new parts. This proposal would also require inspection of the 
intercostals to determine the specification of the material, if 
necessary, and replacement of discrepant parts with new parts. This 
amendment is prompted by a report of cracking in the chassis top strut 
support intercostal in the side bracing structure inside the wing due 
to the effects of metal fatigue. The actions specified by this AD are 
intended to prevent such fatigue-related cracking, which could lead to 
the failure of the chassis side bracing structure inside the wings and 
consequent reduced structural integrity of the chassis support 
structure.

DATES: Effective on February 3, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 3, 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) 227-1320.

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 series airplanes was published in the 
Federal Register on September 9, 1994 (59 FR 46596). That action 
proposed to require repetitive detailed visual inspections to detect 
cracks in the chassis side bracing structure and in the chassis top 
strut support intercostals of the inner wings, and replacement of 
discrepant parts with new parts. That action also proposed to require 
an eddy current inspection to determine the specification of the 
material of the intercostals, if necessary, and replacement of 
discrepant parts with new parts.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.
    The commenter supports the proposed rule.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been added to this final rule to clarify this requirement.
    The FAA has recently reviewed the figures it has used over the past 
several years in calculating the economic impact of AD activity. In 
order to account for various inflationary costs in the airline 
industry, the FAA has determined that it is necessary to increase the 
labor rate used in these calculations from $55 per work hour to $60 per 
work hour. The economic impact information, below, has been revised to 
reflect this increase in the specified hourly labor rate.
    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 25 Model Viscount 744 and 745D series 
airplanes of U.S. registry will be affected by this AD, that it will 
take approximately 15 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 $22,500, or $900 per airplane, per 
inspection cycle.
    The FAA estimates that 4 Model Viscount 810 series airplanes of 
U.S. registry will be affected by this AD, that it will take 
approximately 15 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 proposed AD on U.S. 
operators is estimated to be $3,600, or $900 per airplane, per 
inspection cycle.
    Based on the above figures, the total cost impact of the actions 
proposed by this AD on U.S. operators is estimated to be $26,100, or 
$900 per airplane, per inspection cycle.
    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 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. [[Page 330]] 

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:

94-26-14 British Aerospace Regional Aircraft Limited (Formerly 
British Aerospace Commercial Aircraft Limited, Vickers-Armstrongs 
Aircraft Limited): Amendment 39-9109. Docket 94-NM-108-AD.

    Applicability: All Model Viscount 744, 745D, and 810 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 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 reduced structural integrity of the chassis, 
accomplish the following:
    (a) Within 6 months after the effective date of this AD, perform 
a detailed visual inspection to detect cracks in the chassis side 
bracing structure and in the chassis top strut support intercostals 
inside the wings between stations 81 and 96, in accordance with 
British Aerospace Viscount Preliminary Technical Leaflet (PTL) 332, 
Issue 1, Disc 11 Doc.4, dated December 2, 1991 (for Model Viscount 
744 and 745D series airplanes); or British Aerospace Viscount PTL 
203, Issue 1, Disc 11 Doc.2, dated December 2, 1991 (for Model 
Viscount 810 series airplanes); as applicable.
    (1) If no cracking is detected in the chassis side bracing 
structure, repeat the inspection thereafter at intervals not to 
exceed 1,500 flight hours or 14 months, whichever occurs first.
    (2) If any cracking is detected in the chassis side bracing 
structure, prior to further flight, replace the cracked side of the 
bracing structure with a new structure, in accordance with the 
applicable PTL.
    (3) If no cracking is detected in the chassis top strut support 
intercostal, prior to further flight, perform an eddy current 
inspection to determine the specification of the material (either 
L72 or L73) of the intercostals, in accordance with the applicable 
PTL.
    (i) If the material is manufactured from L72, prior to further 
flight, replace the chassis top strut support intercostal with a new 
chassis top strut support intercostal, in accordance with the 
applicable PTL.
    (ii) If the material is manufactured from L73, no further action 
is required by paragraph (a)(3) of this AD.
    (4) If cracking is detected in the chassis top strut support 
intercostal, prior to further flight, replace it with a new chassis 
top strut support intercostal, in accordance with the applicable 
PTL.
    (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.
    (d) The inspections and replacements shall be done in accordance 
with British Aerospace Viscount Preliminary Technical Leaflet (PTL) 
332, Issue 1, Disc 11 Doc.4, dated December 2, 1991 (for Model 
Viscount 744 and 745D series airplanes); or British Aerospace 
Viscount PTL 203, Issue 1, Disc 11 Doc.2, dated December 2, 1991 
(for Model Viscount 810 series airplanes); as applicable. 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.
    (e) This amendment becomes effective on February 3, 1995.

    Issued in Renton, Washington, on December 21, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-49 Filed 1-3-95; 8:45 am]
BILLING CODE 4910-13-U