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[Federal Register Volume 77, Number 79 (Tuesday, April 24, 2012)]
[Rules and Regulations]
[Pages 24344-24347]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-9393]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-1069; Directorate Identifier 2011-NM-025-AD; 
Amendment 39-17025; AD 2012-08-08]
RIN 2120-AA64

Airworthiness Directives; Learjet Inc.

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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[[Page 24345]]

SUMMARY: We are adopting a new airworthiness directive (AD) for all 
Learjet Inc., Model 45 airplanes. This AD was prompted by changes to 
the Airworthiness Limitations Section (ALS) of the maintenance manual, 
which adds life-limits, revises life-limits, or adds inspections not 
previously identified. This AD requires revising the maintenance 
program to include new or more restrictive life-limits and inspections. 
We are issuing this AD to limit exposure of flight critical components 
to corrosion, cracking, or failure due to life-limits, which if not 
corrected, could result in loss of roll control, fatigue cracking, or 
loss of structural components.

DATES: This AD is effective May 29, 2012.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of May 29, 2012.

ADDRESSES: For service information identified in this AD, contact 
Learjet, Inc., One Learjet Way, Wichita, Kansas 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, Washington. 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: William Griffith, Aerospace Engineer, 
Airframe Branch, ACE-118W, FAA, Wichita Aircraft Certification Office, 
1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 
67209; phone: 316-946-4116; fax: 316-946-4107; email: 
William.E.Griffith@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. 
That NPRM was published in the Federal Register on October 19, 2011 (76 
FR 64851). That NPRM proposed to require revising the maintenance 
program to include new or more restrictive life-limits and inspections.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comment received on the proposal 
and the FAA's response to the comment.

Request To Revisit Interpretation of the Meaning of the Word 
``Current''

    Flight Concepts requested we revisit our interpretation of the word 
``current'' so that the improper use of the airworthiness directive 
system would not be needed. This commenter justified its request by 
providing Webster's definition of the word ``current.''
    We infer that the requested change is in reference to an FAA 
memorandum regarding the legal interpretation of section 91.409(f)(3) 
of the Federal Aviation Regulations (14 CFR 91.409) and is not 
specifically applicable to this AD.
    We do not agree that the word ``current'' needs to be defined for 
this AD. The utilization of the word ``current'' is not within the 
textual body of this AD. This AD requires revising the maintenance 
program by incorporating certain tasks, which when performed, address 
unsafe conditions. Operators utilizing earlier versions of manual-
specific maintenance programs may not be bound or obligated to follow 
newer releases or updates to these maintenance programs. The issue of 
the terminology of the word ``current'' and explanation of the 
requirement for FAA mandates to newer maintenance actions via the AD 
process is addressed in an FAA memorandum dated August 13, 2010, from 
the Office of the Chief Counsel. This AD ensures that those specific 
tasks covering the unsafe conditions are followed by all operators of 
this airplane model. We have not changed the AD in this regard.

Explanation of Additional Changes Made to This AD

    We have redesignated Note 1 of the NPRM (76 FR 64851, October 19, 
2011) as paragraph (c)(2) of this AD, paragraph (c) as paragraph (c)(1) 
of this AD, and Note 2 of the NPRM as Note 1 to paragraph (g) of this 
AD.
    IRN  N3220105 was incorrectly included in table 1 of the 
NPRM (76 FR 64851, October 19, 2011). We have removed it from the final 
rule.

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 (76 FR 64851, October 19, 2011) for correcting the unsafe 
condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (76 FR 64851, October 19, 2011).

Costs of Compliance

    We estimate that this AD affects 336 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                    Cost per       Cost on U.S.
               Action                        Labor cost           Parts cost        product         operators
----------------------------------------------------------------------------------------------------------------
Change ALS in maintenance manual....  1 work-hour x $85 per                $0              $85          $28,560
                                       hour = $85.
----------------------------------------------------------------------------------------------------------------

 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

[[Page 24346]]

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):

2012-08-08 Learjet Inc.: Amendment 39-17025; Docket No. FAA-2011-
1069; Directorate Identifier 2011-NM-025-AD.

(a) Effective Date

    This AD is effective May 29, 2012.

(b) Affected ADs

    None

(c) Applicability

    (1) This AD applies to all Learjet Inc., Model 45 airplanes, 
certificated in any category.
    (2) This AD requires revisions to certain operator maintenance 
documents to include new actions (e.g. inspections). Compliance with 
these actions is required by 14 CFR 91.403(c). For airplanes that 
have been previously modified, altered, or repaired in the areas 
addressed by these actions, the operator may not be able to 
accomplish the inspections described in the revisions. In this 
situation, to comply with 14 CFR 91.403(c), the operator must 
request approval for an alternative method of compliance according 
to paragraph (i) of this AD. The request should include a 
description of changes to the required actions that will ensure the 
continued operational safety of the airplane. The FAA has provided 
guidance for this determination in FAA Advisory Circular (AC) 
25.1529-1A, dated November 20, 2007. http://rgl.faa.gov/Regulatory--
and--Guidance--Library/rgAdvisoryCircular.nsf/list/AC%2025.1529-1A/
$FILE/AC%2025.1529-1A.pdf.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 05, Periodic Inspections.

(e) Unsafe Condition

    This AD was prompted by changes to the Airworthiness Limitations 
Section (ALS) of the maintenance manual (MM), which adds life-
limits, revises life-limits, or adds inspections not previously 
identified. We are issuing this AD to limit exposure of flight 
critical components to corrosion, cracking, or failure due to life-
limits, which if not corrected, could result in loss of roll 
control, fatigue cracking, or loss of structural components.

(f) Compliance

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

(g) Maintenance Program Revision

    Within 90 days after the effective date of this AD, revise the 
maintenance program by incorporating the applicable inspection 
reference number (IRN) tasks identified in table 1 of this AD, as 
specified in Chapter 04, Airworthiness Limitations, of the 
Bombardier Learjet 45 Maintenance Manual MM-104, Revision 53, dated 
January 10, 2011; or Bombardier Learjet 40 Maintenance Manual MM-
105, Revision 21, dated January 10, 2011; as applicable. The initial 
task compliance time is within 90 days after the effective date of 
this AD, or the applicable initial compliance time specified in 
table 1 of this AD, whichever is later.
    Note 1 to paragraph (g) of this AD: IRN R2710041 shown 
in table 1 of this AD is identified as IRN  N2710041 in 
prior revisions of Bombardier Learjet 45 Maintenance Manual MM-104, 
and Bombardier Learjet 40 Maintenance Manual MM-105.

                                           Table 1--IRN Task Revision
----------------------------------------------------------------------------------------------------------------
                                                                                          Chapter 04 of these
              Model--                  IRN --      Initial compliance time--         documents--
----------------------------------------------------------------------------------------------------------------
Model 40, 45......................  R2710041.............  Within 10 years after the   Bombardier Learjet 45
                                                            date of issuance of the     Maintenance Manual MM-
                                                            original standard           104, Revision 53, dated
                                                            airworthiness certificate   January 10, 2011; or
                                                            or the date of issuance     Bombardier Learjet 40
                                                            of the original export      Maintenance Manual MM-
                                                            certificate of              105, Revision 21, dated
                                                            airworthiness, or within    January 10, 2011; as
                                                            10 years after the most     applicable.
                                                            recent replacement,
                                                            whichever occurs later.
Model 40, 45......................  Q5510091.............  Within 600 flight hours     Bombardier Learjet 45
                                                            after the most recent       Maintenance Manual MM-
                                                            inspection done in          104, Revision 53, dated
                                                            accordance with IRN         January 10, 2011; or
                                                             Q5510091.         Bombardier Learjet 40
                                                                                        Maintenance Manual MM-
                                                                                        105, Revision 21, dated
                                                                                        January 10, 2011; as
                                                                                        applicable.
Model 40, 45......................  Q5530011.............  Before the accumulation of  Bombardier Learjet 45
                                                            9,600 total flight hours.   Maintenance Manual MM-
                                                                                        104, Revision 53, dated
                                                                                        January 10, 2011; or
                                                                                        Bombardier Learjet 40
                                                                                        Maintenance Manual MM-
                                                                                        105, Revision 21, dated
                                                                                        January 10, 2011; as
                                                                                        applicable.
Model 40, 45......................  P3220007.............  Within 48 months after the  Bombardier Learjet 45
                                                            most recent inspection      Maintenance Manual MM-
                                                            done in accordance with     104, Revision 53, dated
                                                            IRN  P3220007.     January 10, 2011; or
                                                                                        Bombardier Learjet 40
                                                                                        Maintenance Manual MM-
                                                                                        105, Revision 21, dated
                                                                                        January 10, 2011; as
                                                                                        applicable.

[[Page 24347]]

 
Model 40, 45......................  P3220146.............  Before the accumulation of  Bombardier Learjet 45
                                                            4,800 total landings.       Maintenance Manual MM-
                                                                                        104, Revision 53, dated
                                                                                        January 10, 2011; or
                                                                                        Bombardier Learjet 40
                                                                                        Maintenance Manual MM-
                                                                                        105, Revision 21, dated
                                                                                        January 10, 2011; as
                                                                                        applicable.
Model 40, 45......................  N3220012, N3220023,    Before the accumulation of  Bombardier Learjet 45
                                     N3220035, N3220036,    10,000 total landings on    Maintenance Manual MM-
                                     and N3220037.          the component.              104, Revision 53, dated
                                                                                        January 10, 2011; or
                                                                                        Bombardier Learjet 40
                                                                                        Maintenance Manual MM-
                                                                                        105, Revision 21, dated
                                                                                        January 10, 2011; as
                                                                                        applicable.
Model 40, 45......................  N3220103, N3220104,    Before the accumulation of  Bombardier Learjet 45
                                     and N3220106.          17,000 total landings on    Maintenance Manual MM-
                                                            the component.              104, Revision 53, dated
                                                                                        January 10, 2011; or
                                                                                        Bombardier Learjet 40
                                                                                        Maintenance Manual MM-
                                                                                        105, Revision 21, dated
                                                                                        January 10, 2011; as
                                                                                        applicable.
Model 45..........................  N5710147, N5710171,    Before the accumulation of  Bombardier Learjet 45
                                     and N5710173.          6,500 total flight hours.   Maintenance Manual MM-
                                                                                        104, Revision 53, dated
                                                                                        January 10, 2011.
Model 45..........................  N5710175.............  Before the accumulation of  Bombardier Learjet 45
                                                            6,900 total flight hours.   Maintenance Manual MM-
                                                                                        104, Revision 53, dated
                                                                                        January 10, 2011.
Model 45..........................  N5710177.............  Before the accumulation of  Bombardier Learjet 45
                                                            7,000 total flight hours.   Maintenance Manual MM-
                                                                                        104, Revision 53, dated
                                                                                        January 10, 2011.
----------------------------------------------------------------------------------------------------------------

(h) No Alternative Intervals

    After accomplishing the revisions required by paragraph (g) of 
this AD, no alternative IRN task or IRN task interval may be used 
unless the IRN task or IRN task interval is approved as an AMOC in 
accordance with the procedures specified in paragraph (i)(1) of this 
AD.

(i) 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.

(j) Related Information

    For more information about this AD, William Griffith, Aerospace 
Engineer, Airframe Branch, ACE-118W, FAA, Wichita Aircraft 
Certification Office, 1801 Airport Road, Room 100, Mid-Continent 
Airport, Wichita, Kansas 67209; phone: 316-946-4116; fax: 316-946-
4107; email: William.E.Griffith@faa.gov.

(k) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) of the following service information under 5 U.S.C. 
552(a) and 1 CFR part 51:
    (i) Chapter 04, Airworthiness Limitations, of the Bombardier 
Learjet 45 Maintenance Manual MM-104, Revision 53, dated January 10, 
2011. Only the title page and record of revisions pages of this 
document specify the revision level of the document.
    (ii) Chapter 04, Airworthiness Limitations, of the Bombardier 
Learjet 40 Maintenance Manual MM-105, Revision 21, dated January 10, 
2011. Only the title page and record of revisions pages of this 
document specify the revision level of the document.
    (2) For service information identified in this AD, contact 
Learjet, Inc., One Learjet Way, Wichita, Kansas 67209-2942; 
telephone 316-946-2000; fax 316-946-2220; email 
ac.ict@aero.bombardier.com; Internet http://www.bombardier.com.
    (3) You may review copies of the referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, Washington. For information on the availability of this 
material at the FAA, call 425-227-1221.
    (4) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at an NARA facility, call 202-741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Renton, Washington, on April 9, 2012.
John Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-9393 Filed 4-23-12; 8:45 am]
BILLING CODE 4910-13-P
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