[Federal Register Volume 61, Number 168 (Wednesday, August 28, 1996)]
[Rules and Regulations]
[Pages 44156-44157]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-21742]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-240-AD; Amendment 39-9725; AD 96-18-01]
RIN 2120-AA64
Airworthiness Directives; Learjet Model 60 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 Learjet Model 60 airplanes, that requires
modification of the aft core cowl nozzle of the engine nacelles. This
amendment is prompted by a report that the sealant material in the aft
core cowl nozzle of the engine nacelle was found to extend higher than
the nozzle's forward flange, which can allow it to interfere with the
proper operation of the emergency fuel shutoff actuating mechanism. The
actions specified by this AD are intended to prevent physical
interference of the emergency fuel shutoff actuating mechanism and
resultant engine shutdown.
DATES: Effective October 2, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of October 2, 1996.
ADDRESSES: The service information referenced in this AD may be
obtained from Learjet, Inc., One Learjet Way, Wichita, Kansas 67209-
2942. 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 FAA, Wichita
Aircraft Certification Office, Small Airplane Directorate, 1801 Airport
Road, Room 100, Mid-Continent Airport, Wichita, Kansas; or at the
Office of the Federal Register, 800 North Capitol Street, NW., suite
700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Jeffrey Janusz, Aerospace Engineer,
Systems and Propulsion Branch, ACE-116W, FAA, Small Airplane
Directorate, Wichita Aircraft Certification Office, 1801 Airport Road,
Room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316)
946-4148; fax (316) 946-4407.
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 Learjet Model 60 airplanes
was published in the Federal Register on May 30, 1996 (61 FR 27030).
That action proposed to require modification of the aft core cowl
nozzle of the engine nacelles.
Comments
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.
Cost Impact
There are approximately 39 Learjet Model 60 airplanes of the
affected design in the worldwide fleet. The FAA estimates that 26
airplanes of U.S. registry will be affected by this AD, that it will
take approximately 44 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 the
operators. Based on these figures, the cost impact of the AD on U.S.
operators is estimated to be $68,640, or $2,640 per airplane.
The 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.
Regulatory Impact
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.
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. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
96-18-01 Learjet: Amendment 39-9725. Docket 95-NM-240-AD.
Applicability: Model 60 airplanes, as listed in Learjet Service
Bulletin SB 60-71-2, dated May 12, 1995; certificated in any
category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise 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 (b) 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 prevent the sealant material in the aft core cowl nozzle of
the engine nacelles from interfering with the lever of the emergency
fuel shutoff actuating mechanism, which could result in the failure
of the emergency fuel shutoff actuating mechanism and resultant
engine shutdown, accomplish the following:
(a) Within 90 days after the effective date of this AD, modify
the aft core cowl nozzle of the engine nacelles in accordance with
Learjet Service Bulletin SB 60-71-2, dated May 12, 1995.
(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, Wichita Aircraft Certification
Office (ACO), FAA, Small Airplane Directorate. Operators shall
[[Page 44157]]
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Wichita ACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Wichita ACO.
(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 modification shall be done in accordance with Learjet
Service Bulletin SB 60-71-2, dated May 12, 1995, which includes
Nordam Service Bulletin PW300L71-1, dated April 26, 1995. 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 Learjet, Inc., One Learjet Way,
Wichita, Kansas 67209-2942. Copies may be inspected at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the FAA, Wichita Aircraft Certification Office,
Small Airplane Directorate, 1801 Airport Road, Room 100, Mid-
Continent Airport, Wichita, Kansas; or at the Office of the Federal
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(e) This amendment becomes effective on October 2, 1996.
Issued in Renton, Washington, on August 20, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-21742 Filed 8-27-96; 8:45 am]
BILLING CODE 4910-13-U
