[Federal Register: August 20, 2003 (Volume 68, Number 161)]
[Rules and Regulations]
[Page 50057-50058]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20au03-6]
[[Page 50057]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2002-NM-13-AD; Amendment 39-13283; AD 2003-17-08]
RIN 2120-AA64
Airworthiness Directives; Learjet Model 45 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to certain Learjet Model 45 airplanes, that currently
requires repetitive application of grease to the rotating disk assembly
of the nose landing gear (NLG) squat switch mechanism. This amendment
requires replacement of the squat switch camrod of the NLG, which
terminates the repetitive application; and also reduces the
applicability of the existing AD. The actions specified by this AD are
intended to prevent moisture contamination and subsequent formation of
ice which could cause bending and damage of the squat switch assembly,
driving the nose wheel to an uncommanded angle against the force of the
steering system. This condition, if not corrected, could result in the
airplane departing the runway at high speeds during landing. This
action is intended to address the identified unsafe condition.
DATES: Effective September 24, 2003.
The incorporation by reference of Bombardier Service Bulletin SB
45-32-8, Revision 2, dated March 14, 2001, as listed in the
regulations, is approved by the Director of the Federal Register as of
September 24, 2003.
The incorporation by reference of Bombardier Service Information
Letter SIL 32-016, dated March 30, 2000, as listed in the regulations,
was approved previously by the Director of the Federal Register as of
December 6, 2000 (65 FR 65257, November 1, 2000).
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 Wichita Aircraft
Certification Office, 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: Robert Busto, Aerospace Engineer,
Systems and Equipment Branch, ACE-116W, FAA, Wichita Aircraft
Certification Office, 1801 Airport Road, Room 100, Mid-Continent
Airport, Wichita, Kansas 67209; telephone (316) 946-4157; fax (316)
946-4107.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) by superseding AD 2000-22-04,
amendment 39-11950 (65 FR 65257, November 1, 2000), which is applicable
to certain Learjet 45 series airplanes, was published in the Federal
Register on May 29, 2003 (68 FR 31999). The action proposed to require
repetitive application of grease to the rotating disk assembly of the
nose landing gear (NLG) squat switch mechanism. The action also
proposed to require replacement of the squat switch camrod of the NLG,
which would terminate the repetitive application; and would reduce the
applicability of the existing AD. That action was prompted by tests
conducted by the manufacturer that indicated a potential unsafe
condition exists involving damage or bending of the squat switch
assembly of the NLG due to moisture contamination and subsequent
formation of ice.
Comments
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.
Conclusion
The FAA has determined that air safety and the public interest
require the adoption of the rule as proposed.
Changes to 14 CFR Part 39/Effect on the AD
On July 10, 2002, the FAA issued a new version of 14 CFR part 39
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness
directives system. The regulation now includes material that relates to
altered products, special flight permits, and alternative methods of
compliance (AMOCs). Because we have now included this material in part
39, only the office authorized to approve AMOCs is identified in each
individual AD. However, for clarity and consistency in this final rule,
we have retained the language of the NPRM regarding that material.
Change to Labor Rate Estimate
We have reviewed the figures we have used over the past several
years to calculate AD costs to operators. To account for various
inflationary costs in the airline industry, we find it necessary to
increase the labor rate used in these calculations from $60 per work
hour to $65 per work hour. The cost impact information, below, reflects
this increase in the specified hourly labor rate.
Cost Impact
There are approximately 110 airplanes of U.S. registry that will be
affected by this AD.
The actions that are currently required by AD 2000-22-04 take
approximately 1 work hour per airplane to accomplish, at an average
labor rate of $65 per work hour. Based on these figures, the cost
impact of the previously required actions on U.S. operators is
estimated to be $7,150, or $65 per airplane.
The new actions that are required by this new AD will take
approximately 3 work hours per airplane to accomplish, at an average
labor rate of $65 per work hour. Required parts will cost approximately
$205 per airplane. Based on these figures, the cost impact of the new
requirements of this AD on U.S. operators is estimated to be $44,000,
or $400 per airplane.
The cost impact figures discussed above are 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 cost impact figures discussed
in AD rulemaking actions represent only the time necessary to perform
the specific actions actually required by the AD. These figures
typically do not include incidental costs, such as the time required to
gain access and close up, planning time, or time necessitated by other
administrative actions.
Regulatory Impact
The regulations adopted herein will not have a substantial direct
effect 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, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
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
[[Page 50058]]
``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
0
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
0
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]
0
2. Section 39.13 is amended by removing amendment 39-11950 (65 FR
65257, November 1, 2000), and by adding a new airworthiness directive
(AD), amendment 39-13283, to read as follows:
2003-17-08 Learjet: Amendment 39-13283. Docket 2002-NM-13-AD.
Supersedes AD 2000-22-04, Amendment 39-11950.
Applicability: Model 45 airplanes, certificated in any category;
serial numbers (S/N) 45-005 through 45-071 inclusive, that have been
modified per Bombardier Service Bulletin 45-32-3; and S/Ns 45-072
through 45-114 inclusive.
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 (c)(1)
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 moisture contamination and subsequent formation of
ice which could cause bending and damage of the squat switch
assembly of the nose landing gear (NLG), driving the nose wheel to
an uncommanded angle against the force of the steering system, and
consequently resulting in the airplane departing the runway at high
speeds during landing, accomplish the following:
Restatement of Requirements of AD 2000-22-04, Amendment 39-11950
Application of Grease
(a) Within 30 days after December 6, 2000 (the effective date of
AD 2000-22-04, amendment 39-11950): Apply grease to the rotating
disk assembly of the squat switch mechanism of the nose wheel in
accordance with Bombardier Service Information Letter SIL 32-016,
dated March 30, 2000. Thereafter, repeat this application at
intervals not to exceed 30 days until the replacement required by
paragraph (b) of this AD is accomplished.
New Requirements of This AD
Terminating Action
(b) Within 300 flight hours or 12 months after the effective
date of this AD, whichever occurs first: Replace the camrod of the
squat switch assembly of the NLG with a new assembly in accordance
with the Accomplishment Instructions of Bombardier Service Bulletin
SB 45-32-8, Revision 2, dated March 14, 2001. Accomplishment of the
camrod replacement terminates the requirements of this AD.
Alternative Methods of Compliance
(c)(1) 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. Operators shall submit their requests through an
appropriate FAA Principal Maintenance Inspector, who may add
comments and then send it to the Manager, Wichita ACO.
(2) Alternative methods of compliance, approved previously in
accordance with AD 2000-22-04, amendment 39-11950, are approved as
alternative methods of compliance with this AD.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Wichita ACO.
Special Flight Permits
(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.
Incorporation by Reference
(e) The actions shall be done in accordance with Bombardier
Service Information Letter SIL 32-016, dated March 30, 2000; and
Bombardier Service Bulletin SB 45-32-8, Revision 2, dated March 14,
2001; as applicable.
(1) The incorporation by reference of Bombardier Service
Bulletin SB 45-32-8, Revision 2, dated March 14, 2001, is approved
by the Director of the Federal Register in accordance with 5 U.S.C.
552(a) and 1 CFR part 51.
(2) The incorporation by reference of Bombardier Service
Information Letter SIL 32-016, dated March 30, 2000, was approved
previously by the Director of the Federal Register as of December 6,
2000 (65 FR 65257, November 1, 2000).
(3) 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 Wichita Aircraft Certification Office, 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.
Effective Date
(f) This amendment becomes effective on September 24, 2003.
Issued in Renton, Washington, on August 13, 2003.
Kyle L. Olsen,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 03-21155 Filed 8-19-03; 8:45 am]
BILLING CODE 4910-13-P