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[Federal Register Volume 60, Number 68 (Monday, April 10, 1995)]
[Rules and Regulations]
[Pages 17987-17988]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-8445]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-170-AD; Amendment 39-9191; AD 95-08-02]

Airworthiness Directives; Jetstream Model 4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Jetstream Model 4101 airplanes, that requires 
installation of new case drain pipes and an additional fairlead support 
for the hydraulics case drain line in the rear spar area of the engine/
nacelle. This amendment is prompted by reports of fatigue failure of 
the case drain line in the hydraulics system. The actions specified by 
the proposed AD are intended to prevent the loss of main system 
hydraulics as a result of lack of support against vibration and 
subsequent fatigue failure of the case drain line for the hydraulics 
system.

DATES: Effective May 10, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 10, 1995.

ADDRESSES: The service information referenced in this AD may be 
obtained from Jetstream Aircraft, Inc., P.O. Box 16029, Dulles 
International Airport, Washington, DC 20041-6029. 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: Sam Grober, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-1187; 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 certain Jetstream Model 4101 
airplanes series airplanes was published in the Federal Register on 
December 16, 1994 (59 FR 64875). That action proposed to require 
installation of new case drain pipes and an additional fairlead support 
for the hydraulics case drain line in the rear spar area of the engine/
nacelle. -
    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. -
    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 as proposed. -
    The FAA estimates that 9 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 10 work hours per 
airplane to accomplish the required actions, and that the average labor 
rate is $60 per work hour. Required parts will be supplied by the 
manufacturer at no cost to operators. Based on these figures, the total 
cost impact of the AD on U.S. operators is estimated to be $5,400, or 
$600 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 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 17988]] 

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:

95-08-02  Jetstream Aircraft Limited: Amendment 39-9191. Docket 94-
NM-170-AD.

    Applicability: Model 4101 airplanes; constructors numbers 41005 
through 41015 inclusive, 41019 through 41024 inclusive, 41028, and 
41029; 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 the loss of the main system hydraulics, accomplish 
the following:
    (a) Within 4 months after the effective date of this AD, install 
new case drain pipes and an additional fairlead support for the 
hydraulics case drain line in the rear spar area of the engine/
nacelle in accordance with Jetstream Service Bulletin J41-29-005, 
Revision 1, dated August 12, 1994; or Revision 2, dated August 30, 
1994.
    (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, FAA, 
Transport Airplane Directorate, ANM-113. 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 installation shall be done in accordance with the 
following Jetstream service bulletins, as applicable, which contain 
the specified effective pages:

------------------------------------------------------------------------
  Service bulletin                                                      
referenced and date-   Page No.    Revision level    Date shown on page 
                                    shown on page                       
------------------------------------------------------------------------
J41-29-005-........        1, 4-  2...............  Aug. 30, 1994.      
Revision 2                                                              
August 30, 1994....  2, 3, 5-12-  1...............  Aug. 12, 1994.      
J41-29-005-........        1-12-  1-..............  Aug. 12, 1994.      
Revision 1                                                              
August 12, 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 Jetstream Aircraft, Inc., P.O. Box 
16029, Dulles International Airport, Washington, DC 20041-6029. 
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 May 10, 1995.

    Issued in Renton, Washington, on March 31, 1995.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.

[FR Doc. 95-8445 Filed 4-7-95; 8:45 am]

BILLING CODE 4910-13-U
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