Document ID: FAA-2011-1069-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Learjet Inc. Model 45 Airplanes
Posted Date: 2011-10-19T04:00Z

[Federal Register Volume 76, Number 202 (Wednesday, October 19, 2011)]
[Proposed Rules]
[Pages 64851-64854]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-27010]

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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]
RIN 2120-AA64

Airworthiness Directives; Learjet Inc. Model 45 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. This proposed AD would require revising the 
maintenance program to include new or more restrictive life-limits and 
inspections. This proposed 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. We are proposing 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: We must receive comments on this proposed AD by December 5, 
2011.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Learjet, Inc., One Learjet Way, Wichita, Kansas 67209-2942; phone 316-
946-2000; fax 316-946-2220; e-mail ac.ict@aero.bombardier.com; Internet

[[Page 64852]]

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 proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

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; e-mail: 
William.E.Griffith@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2011-1069; 
Directorate Identifier 2011-NM-025-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We have reviewed the design approval holder's changes to the ALS of 
the maintenance manual, which adds life-limits, revises life-limits, or 
adds inspections not previously identified. These changes resulted from 
the design holder's analysis, testing, and in-service history of 
certain components. We are proposing 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. The 
corrective action is revising the maintenance program.

Relevant Service Information

    We reviewed Chapter 04, Airworthiness Limitations, of the 
Bombardier Learjet 45 Maintenance Manual MM-104, Revision 53, dated 
January 10, 2011; and Bombardier Learjet 40 Maintenance Manual MM-105, 
Revision 21, dated January 10, 2011. This service information describes 
component and system checks and replacements and includes new or 
revised life-limits and new inspections.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously.

Costs of Compliance

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

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under the 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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

[[Page 64853]]

    Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13  [Amended]

    2. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

Learjet Inc.: Docket No. FAA-2011-1069; Directorate Identifier 2011-
NM-025-AD.

Comments Due Date

    (a) We must receive comments by December 5, 2011.

Affected ADs

    (b) None

Applicability

    (c) This AD applies to all Learjet Inc. Model 45 airplanes, 
certificated in any category.

    Note 1: 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 Advisory Circular (AC) 25.1529-
1A.

Subject

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

Unsafe Condition

    (e) 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.

Compliance

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

Maintenance Program Revision

    (g) 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 2:  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
------------------------------------------------------------------------
                                            Initial       Chapter 04 of
       Model--         IRN --     compliance         these
                                             time--        documents--
------------------------------------------------------------------------
Model 40, 45.........  R2710041.......  Within 10 years  Bombardier
                                         after the date   Learjet 45
                                         of issuance of   Maintenance
                                         the original     Manual MM-104,
                                         standard         Revision 53,
                                         airworthiness    dated January
                                         certificate or   10, 2011; or
                                         the date of      Bombardier
                                         issuance of      Learjet 40
                                         the original     Maintenance
                                         export           Manual MM-105,
                                         certificate of   Revision 21,
                                         airworthiness,   dated January
                                         or within 10     10, 2011; as
                                         years after      applicable.
                                         the most
                                         recent
                                         replacement,
                                         whichever
                                         occurs later.
Model 40, 45.........  Q5510091.......  Within 600       Bombardier
                                         flight hours     Learjet 45
                                         after the most   Maintenance
                                         recent           Manual MM-104,
                                         inspection       Revision 53,
                                         done in          dated January
                                         accordance       10, 2011; or
                                         with IRN         Bombardier
                                                 Learjet 40
                                         Q5510091.        Maintenance
                                                          Manual MM-105,
                                                          Revision 21,
                                                          dated January
                                                          10, 2011; as
                                                          applicable.
Model 40, 45.........  Q5530011.......  Before the       Bombardier
                                         accumulation     Learjet 45
                                         of 9,600 total   Maintenance
                                         flight hours.    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        Bombardier
                                         months after     Learjet 45
                                         the most         Maintenance
                                         recent           Manual MM-104,
                                         inspection       Revision 53,
                                         done in          dated January
                                         accordance       10, 2011; or
                                         with IRN         Bombardier
                                                 Learjet 40
                                         P3220007.        Maintenance
                                                          Manual MM-105,
                                                          Revision 21,
                                                          dated January
                                                          10, 2011; as
                                                          applicable.
Model 40, 45.........  P3220146.......  Before the       Bombardier
                                         accumulation     Learjet 45
                                         of 4,800 total   Maintenance
                                         landings.        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,        Before the       Bombardier
                        N3220023,        accumulation     Learjet 45
                        N3220035,        of 10,000        Maintenance
                        N3220036, and    total landings   Manual MM-104,
                        N3220037.        on the           Revision 53,
                                         component.       dated January
                                                          10, 2011; or
                                                          Bombardier
                                                          Learjet 40
                                                          Maintenance
                                                          Manual MM-105,
                                                          Revision 21,
                                                          dated January
                                                          10, 2011; as
                                                          applicable.

[[Page 64854]]

 
Model 40, 45.........  N3220103,        Before the       Bombardier
                        N3220104,        accumulation     Learjet 45
                        N3220105, and    of 17,000        Maintenance
                        N3220106.        total landings   Manual MM-104,
                                         on the           Revision 53,
                                         component.       dated January
                                                          10, 2011; or
                                                          Bombardier
                                                          Learjet 40
                                                          Maintenance
                                                          Manual MM-105,
                                                          Revision 21,
                                                          dated January
                                                          10, 2011; as
                                                          applicable.
Model 45.............  N5710147,        Before the       Bombardier
                        N5710171, and    accumulation     Learjet 45
                        N5710173.        of 6,500 total   Maintenance
                                         flight hours.    Manual MM-104,
                                                          Revision 53,
                                                          dated January
                                                          10, 2011.
Model 45.............  N5710175.......  Before the       Bombardier
                                         accumulation     Learjet 45
                                         of 6,900 total   Maintenance
                                         flight hours.    Manual MM-104,
                                                          Revision 53,
                                                          dated January
                                                          10, 2011.
Model 45.............  N5710177.......  Before the       Bombardier
                                         accumulation     Learjet 45
                                         of 7,000 total   Maintenance
                                         flight hours.    Manual MM-104,
                                                          Revision 53,
                                                          dated January
                                                          10, 2011.
------------------------------------------------------------------------

No Alternative Intervals

    (h) After accomplishing the revisions required by paragraphs (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.

Alternative Methods of Compliance (AMOCs)

    (i)(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.

Related Information

    (j) For more information about this AD, 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; e-mail: William.E.Griffith@faa.gov.
    (k) 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; e-mail 
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.

    Issued in Renton, Washington, on October 5, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-27010 Filed 10-18-11; 8:45 am]
BILLING CODE 4910-13-P