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[Federal Register Volume 78, Number 127 (Tuesday, July 2, 2013)]
[Rules and Regulations]
[Pages 39574-39576]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-15402]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0214; Directorate Identifier 2012-NM-152-AD; 
Amendment 39-17497; AD 2013-13-09]
RIN 2120-AA64

Airworthiness Directives; Learjet Inc. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Learjet Inc. Model 60 airplanes. This AD was prompted by a report of a 
high-speed rejected takeoff caused by all four main landing gear (MLG) 
tires blowing out during the takeoff roll. This AD requires installing 
new rigid hydraulic tube assemblies to the MLG struts; installing a new 
MLG squat switch bracket, modifying the MLG squat switch wire harness; 
modifying the MLG anti-skid wheel transducer electrical wire harnesses; 
routing and securing the anti-skid wheel and squat switch electrical 
wire harnesses to the MLG strut assembly; installing outboard bracket 
assemblies, anti-skid shield, forward electrical cover on the forward 
stiffener, upper and lower inboard bracket assemblies, and clamps that 
support the electrical wire harness; modifying the aft stiffener for 
the new electrical wire harness support; installing the aft electrical 
cover and strap on the aft stiffener; installing a new flat landing 
light lamp if necessary; and, for certain airplanes, installing a new 
wheel speed detect box assembly, nutplates, and brackets and a new 
thrust reverser interface box, and modifying the wiring for the new 
thrust reverser interface box. We are issuing this AD to prevent 
failure of the braking system or adverse operation of the spoiler and 
thrust reverser system due to external damage, particularly from tire 
failure, which could result in loss of control of the airplane.

DATES: This AD is effective August 6, 2013.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of August 6, 
2013.

ADDRESSES: For service information identified in this AD, contact 
Learjet, Inc., One Learjet Way, Wichita, KS 67209-2942; telephone 316-
946-2000; fax 316-946-2220; email ac.ict@aero.bombardier.com; Internet 
http://www.bombardier.com. You may review copies of the referenced 
service information at the FAA, Transport Airplane Directorate, 1601 
Lind Avenue SW., Renton, WA. For information on the availability of 
this material at the FAA, call 425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (phone: 800-647-5527) is Document Management Facility, 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Don Ristow, Aerospace Engineer, 
Mechanical Systems and Propulsion Branch, ACE-116W, FAA, Wichita 
Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-
Continent Airport, Wichita, KS 67209; phone: 316-946-4120; fax: 316-
946-4107; email: donald.ristow@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
The NPRM published in the Federal Register on March 27, 2013 (78 FR 
18531). The NPRM proposed to require installing new rigid hydraulic 
tube assemblies to the MLG struts; installing a new MLG squat switch 
bracket; modifying the MLG squat switch wire harness; modifying the MLG 
anti-skid wheel transducer electrical wire harnesses; routing and 
securing the anti-skid wheel and squat switch electrical wire harnesses 
to the MLG strut assembly; installing outboard bracket assemblies, 
anti-skid shield, forward electrical cover on the forward stiffener, 
upper and lower inboard bracket assemblies, and clamps that support the 
electrical wire harness; modifying the aft stiffener for the new 
electrical wire harness support; installing the aft electrical cover 
and strap on the aft stiffener; installing a new flat landing light 
lamp if necessary; and, for certain airplanes, installing a new wheel 
speed detect box assembly, nutplates, and brackets and a new thrust 
reverser

[[Page 39575]]

interface box, and modifying the wiring for the new thrust reverser 
interface box.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We have considered the comment received. The National 
Transportation Safety Board supported the NPRM (78 FR 18531, March 27, 
2013).

Conclusion

    We reviewed the relevant data, considered the comment received, and 
determined that air safety and the public interest require adopting the 
AD as proposed except for minor editorial changes. We have determined 
that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM (78 FR 18531, March 27, 2013) for correcting the unsafe condition; 
and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (78 FR 18531, March 27, 2013).

Interim Action

    We consider this AD to be the second of three ADs that are related 
to each other, and collectively address unsafe conditions that might 
result from damage to critical components on the landing gear or in the 
wheel well that affect the braking, spoiler, and thrust reverser 
systems. The manufacturer is currently developing a final modification 
for the thrust reverser. Once the new thrust reverser modification is 
developed, approved, and available, we might consider additional 
rulemaking.

Costs of Compliance

    We estimate that this AD affects 275 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Action                          Labor cost          Parts cost           Cost per  product                 Cost on U.S.  operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Installation of rigid hydraulic tube    Up to 53 work-hours x $85       $7,093  Up to $11,598......................  Up to $3,189,450.
 assemblies and MLG squat switch         per hour = $4,505.
 bracket; modification of MLG squat
 switch wire harness and MLG anti-skid
 wheel transducer electrical wire
 harnesses; and routing and securing
 anti-skid wheel and squat switch
 electrical wire harnesses to MLG
 strut assembly (Bombardier Service
 Bulletin 60[dash]32-33, dated July
 23, 2012).
Installation of outboard bracket        Up to 25 work-hours x $85       17,960  Up to $20,085......................  Up to $5,523,375.
 assemblies, anti-skid shield, forward   per hour = $2,125.
 electrical cover, upper and lower
 inboard bracket assemblies, and
 clamps; modification of aft
 stiffener; and installation of aft
 electrical cover and strap, and flat
 landing light lamp (Bombardier
 Service Bulletin 60-57-7, dated July
 23, 2012).
Installation of wheel speed detect box  Up to 65 work-hours x $85        1,154  $6,679.............................  Up to $881,628.
 assembly, nutplates brackets, and       per hour = $5,525.
 thrust reverser interface box; and
 modification of wiring for serial
 numbers 60[dash]002 through 60-276
 (Bombardier Service Bulletin 60-78-7,
 Revision 2, dated May 1, 2006) (132
 U.S. airplanes).
--------------------------------------------------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this AD may be 
covered under warranty, thereby reducing the cost impact on affected 
individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    This AD will not have federalism implications under Executive Order 
13132. This AD 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.
    For the reasons discussed above, I certify that this AD:
    (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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 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. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

2013-13-09 Learjet Inc.: Amendment 39-17497; Docket No. FAA-2013-
0214; Directorate Identifier 2012-NM-152-AD.

(a) Effective Date

    This AD is effective August 6, 2013.

[[Page 39576]]

(b) Affected ADs

    Certain requirements of this AD affect certain requirements of 
AD 2010-11-11, Amendment 39-16316 (75 FR 32255, June 8, 2010).

(c) Applicability

    This AD applies to Learjet Inc. Model 60 airplanes, certificated 
in any category, serial numbers 60-001 through 60-413 inclusive.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 32, Landing gear; 57, Wings; 78, Engine 
exhaust.

(e) Unsafe Condition

    This AD was prompted by a report of a high-speed rejected 
takeoff caused by all four main landing gear (MLG) tires blowing out 
during the takeoff roll. We are issuing this AD to prevent failure 
of the braking system or adverse operation of the spoiler and thrust 
reverser system due to external damage, particularly from tire 
failure, which could result in loss of control of the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Modification and Installation

    Within 600 flight hours or 12 months after the effective date of 
this AD, whichever occurs first: Do the actions required by 
paragraphs (g)(1), (g)(2), and (g)(3) of this AD, as applicable.
    (1) For all airplanes: Install new rigid hydraulic tube 
assemblies to the MLG struts, install a new MLG squat switch bracket 
and modify the MLG squat switch wire harness, modify the MLG anti-
skid wheel transducer electrical wire harnesses, and route and 
secure the anti-skid wheel and squat switch electrical wire 
harnesses to the MLG strut assembly, in accordance with the 
Accomplishment Instructions of Bombardier Service Bulletin 60-32-33, 
dated July 23, 2012.
    (2) For all airplanes: Install outboard bracket assemblies, 
anti-skid shield, forward electrical cover on the forward stiffener, 
upper and lower inboard bracket assemblies, and clamps that support 
the electrical wire harness; modify the aft stiffener for the new 
electrical wire harness support; install the aft electrical cover 
and strap on the aft stiffener; and install a new flat landing light 
lamp, as applicable; in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletin 60-57-7, dated July 23, 
2012.
    (3) For airplanes having serial numbers 60-002 through 60-276 
inclusive: Install a new wheel speed detect box assembly, nutplates, 
brackets, and interface box; and modify the wiring for the new 
thrust reverser interface box; in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletin 60-78-7, Revision 2, 
dated May 1, 2006.

(h) Terminating Action for AD 2010-11-11, Amendment 39-16316 (75 FR 
32255, June 8, 2010)

    After accomplishing the actions required by paragraph (g) of 
this AD, the requirement in paragraph (h) of AD 2010-11-11, 
Amendment 39-16316 (75 FR 32255, June 8, 2010), to check the nose 
and main tire pressures before 96 hours prior to takeoff, is 
terminated. All provisions of paragraphs (g) and (h) of AD 2010-11-
11 that are not specifically referenced by this paragraph remain 
fully applicable and must be complied with.

(i) Credit for Previous Actions

    This paragraph provides credit for the corresponding actions 
specified in paragraph (g)(3) of this AD, if those actions were 
performed before the effective date of this AD using Bombardier 
Service Bulletin SB60-78-7, dated February 21, 2005; or Revision 1, 
dated June 30, 2005; which are not incorporated by reference in this 
AD.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Wichita Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. In accordance with 14 
CFR 39.19, send your request to your principal inspector or local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(k) Related Information

    For more information about this AD, contact Don Ristow, 
Aerospace Engineer, Mechanical Systems and Propulsion Branch, ACE-
116W, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, 
Room 100, Mid-Continent Airport, Wichita, KS 67209; phone: 316-946-
4120; fax: 316-946-4107; email: donald.ristow@faa.gov.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Bombardier Service Bulletin 60-32-33, dated July 23, 2012.
    (ii) Bombardier Service Bulletin 60-57-7, dated July 23, 2012.
    (iii) Bombardier Service Bulletin 60-78-7, Revision 2, dated May 
1, 2006.
    (3) For service information identified in this AD, contact 
Learjet, Inc., One Learjet Way, Wichita, KS 67209-2942; telephone 
316-946-2000; fax 316-946-2220; email ac.ict@aero.bombardier.com; 
Internet http://www.bombardier.com.
    (4) You may view this service information at FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For 
information on the availability of this material at the FAA, call 
425-227-1221.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on June 13, 2013.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-15402 Filed 7-1-13; 8:45 am]
BILLING CODE 4910-13-P
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