
[Federal Register: June 2, 2009 (Volume 74, Number 104)]
[Rules and Regulations]               
[Page 26288-26291]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02jn09-4]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0498; Directorate Identifier 2009-NM-065-AD; 
Amendment 39-15923; AD 2009-11-13]
RIN 2120-AA64

 
Airworthiness Directives; Learjet Model 45 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Learjet Model 45 airplanes. For certain airplanes, this AD requires 
repetitive inspections for chafing and other damage of the case drain 
tube from the hydraulic pump case installed on the left-hand engine, 
and corrective action if necessary. This AD also requires, for all 
airplanes, repetitive inspections for discrepancies of the left 
engine's nacelle tubing, repetitive inspections for evidence of fluid 
leakage within the left engine accessory compartment, and corrective 
actions if necessary. This AD was prompted by reports of chafed 
hydraulic tubes in the left-hand engine. We are issuing this AD to 
detect and correct chafed hydraulic tubes in the left-hand engine and 
consequent hydraulic tube failure and uncontrolled loss of flammable 
fluid within the engine cowling, which could result in a fire in the 
engine nacelle and loss of control of the airplane.

DATES: This AD is effective June 17, 2009.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of June 17, 2009.
    We must receive comments on this AD by August 3, 2009.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    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.

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 street address for 
the Docket Office (telephone 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: James P. Galstad, Aerospace Engineer, 
Systems and Propulsion Branch, ACE-116W, FAA, Wichita Aircraft 
Certification Office, 1801 Airport Road, Room 100, Mid-Continent 
Airport, Wichita, Kansas 67209; telephone (316) 946-4135; fax (316) 
946-4107.

SUPPLEMENTARY INFORMATION:

Discussion

    We have received reports of chafing found on hydraulic tubing in 
the left-hand engine. Specifically, the chafing was found on a case 
drain tube from the hydraulic pump case installed on the left-hand 
engine, on the lower forward cowl latch structure on the inboard side 
of the engine. Chafing was also found on a hydraulic pressure tube, on 
the hydraulic case drain tube on the left-hand engine, and on the 
hydraulic supply tube on the oil reservoir on the left-hand engine. 
Chafed hydraulic tubes in the left-hand engine and consequent hydraulic 
tube failure and uncontrolled loss of flammable fluid within the engine 
cowling, if not corrected, could result in a fire in the engine nacelle 
and loss of control of the airplane.

Relevant Service Information

    We reviewed the following service bulletins:
     Bombardier Alert Service Bulletin A45-29-15, dated 
December 26, 2006.
     Bombardier Alert Service Bulletin A40-29-03, dated 
December 26, 2006.
    The service bulletins describe procedures for a detailed inspection 
for chafing and other damage of the case drain tube from the hydraulic 
pump case installed on the left-hand engine. The service bulletins also 
describe procedures for repositioning any tube that has damage within 
certain limits and replacing any tube that has damage that exceeds 
those limits.
    We have reviewed the following temporary revisions (TRs):
     Learjet 40 Temporary Revision (TR) 71-1, dated April 28, 
2009, to the Learjet 40 Maintenance Manual MM-105.
     Learjet 45 TR 71-1, dated April 28, 2009, to the Learjet 
45 Maintenance Manual MM-104.
    The TRs describe procedures for repetitive detailed inspections for 
discrepancies, including damage to the left engine's nacelle tubing and 
inadequate clearance between any unsupported section of the tube or 
other tubing and surrounding components. The TRs also describe 
procedures for adjusting the tubing and clamping to achieve minimum 
clearance and replacing any tube that has damage exceeding certain 
limits.
    We have reviewed the engine--maintenance practices in the following 
maintenance manual documents:
     Learjet 45 Maintenance Manual MM-104, Revision 47, dated 
March 30, 2009, Powerplant-Maintenance Practices Section 71-00-00 and 
Engine-Maintenance Practices Section 71-00-01 (for M45 airplanes).
     Learjet 40 Maintenance Manual MM-105, Revision 15, dated 
March 30, 2009, Engine-Maintenance Practices Section 71-00-01 (for M40 
airplanes).
    The engine-maintenance practices sections in the maintenance 
manuals (MMs) describe procedures for a general visual inspection for 
evidence of engine oil, hydraulic fluid, or fuel leakage within the 
left engine accessory compartment. For airplanes on which there is 
evidence of leakage, the MMs describe procedures for removing each 
plumbing clamp within the area affected

[[Page 26289]]

by the service bulletins and MM TRs identified in this AD, and cleaning 
and removing all evidence of fluid leakage. Tubing clamps that are 
associated with inadequate clearance are replaced with new clamps.

FAA's Determination and Requirements of This AD

    We are issuing 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. 
This AD requires accomplishing the actions specified in the service 
information described previously, except as discussed below.

Differences Between the AD and the Service Information

    Although the service bulletins provide for one-time inspections, 
this AD requires that those inspections be repeated, until a 
terminating action can be accomplished to adequately address the 
identified unsafe condition. This difference has been coordinated with 
the manufacturer.

Interim Action

    We consider this AD interim action. The manufacturer is currently 
developing a modification that will address the unsafe condition 
identified in this AD. Once this modification is developed, approved, 
and available, we might consider additional rulemaking.

FAA's Justification and Determination of the Effective Date

    Chafed hydraulic tubes in the left-hand engine and consequent 
hydraulic tube failure and uncontrolled loss of flammable fluid within 
the engine cowling could result in a fire in the engine nacelle and 
loss of control of the airplane. Because of our requirement to promote 
safe flight of civil aircraft and thus the critical need to ensure the 
proper functioning of the affected systems, and because of the short 
compliance time involved with this action, this AD must be issued 
immediately.
    Because an unsafe condition exists that requires the immediate 
adoption of this AD, we find that notice and opportunity for prior 
public comment hereon are impracticable and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not provide you with notice and an opportunity to 
provide your comments before it becomes effective. However, we invite 
you to send any written data, views, or arguments about this AD. Send 
your comments to an address listed under the ADDRESSES section. Include 
``Docket No. FAA-2009-0498; Directorate Identifier 2009-NM-065-AD'' at 
the beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of this 
AD. We will consider all comments received by the closing date and may 
amend this 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 AD.

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), 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

0
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 AD:

2009-11-13 Learjet: Amendment 39-15923. Docket No. FAA-2009-0498; 
Directorate Identifier 2009-NM-065-AD.

Effective Date

    (a) This airworthiness directive (AD) is effective June 17, 
2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Learjet Model 45 airplanes, certificated 
in any category, serial numbers 45-002 through 45-4000 inclusive.

Subject

    (d) Air Transport Association (ATA) of America Code 29: 
Hydraulic power.

Unsafe Condition

    (e) This AD results from reports of chafed hydraulic tubes in 
the left-hand engine. The Federal Aviation Administration is issuing 
this AD to detect and correct chafed hydraulic tubes in the left-
hand engine and consequent hydraulic tube failure and uncontrolled 
loss of flammable fluid within the engine cowling, which could 
result in a fire in the engine nacelle and loss of control of the 
airplane.

Compliance

    (f) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Repetitive Inspections: Case Drain Tube

    (g) For airplanes having serial numbers identified in Table 1 of 
this AD: Within 50 flight hours after the effective date of this AD, 
do a detailed inspection for chafing and other damage of the case 
drain tube from the hydraulic pump case installed on the left-hand 
engine, in accordance with the applicable service bulletin 
identified in Table 1 of this AD. If any damage is found, before 
further flight, reposition or replace the tube,

[[Page 26290]]

as applicable, in accordance with the Accomplishment Instructions of 
the service bulletin identified in Table 1 of this AD, as 
applicable. Repeat the inspection thereafter at intervals not to 
exceed 150 flight hours.

               Table 1--Service Bulletins for Inspections
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                 For--                                Use--
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Serial numbers 45-005 through 45-313     Bombardier Alert Service
 inclusive (commonly referred to as       Bulletin A45-29-15, dated
 ``M45'' airplanes).                      December 26, 2006.
Serial numbers 45-2001 through 45-2063   Bombardier Alert Service
 inclusive (commonly referred to as       Bulletin A40-29-03, dated
 ``M40'' airplanes).                      December 26, 2006.
------------------------------------------------------------------------


    Note 1: For the purposes of this AD, a detailed inspection is: 
``An intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at an intensity deemed appropriate. Inspection aids such as 
mirror, magnifying lenses, etc., may be necessary. Surface cleaning 
and elaborate procedures may be required.''

Repetitive Inspections: Nacelle Tubing

    (h) Within 50 flight hours after the effective date of this AD, 
do a detailed inspection for discrepancies of the left engine's 
nacelle tubing, in accordance with the applicable temporary revision 
(TR) identified in Table 2 of this AD. Discrepancies include damaged 
tubing, and inadequate clearance between any unsupported section of 
the tube or other tubing and surrounding components. If any 
discrepancy is found, before further flight, adjust the tubing and 
clamping or replace the tubing, as applicable, in accordance with 
the applicable TR identified in Table 2 of this AD. Repeat the 
inspection thereafter at intervals not to exceed 150 flight hours.

                      Table 2--TRs for Inspections
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                 For--                                Use--
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Serial numbers 45-2001 through 45-4000   Learjet 40 TR 71-1, dated April
 inclusive (commonly referred to as       28, 2009, to the Learjet 40
 ``M40'' airplanes).                      Maintenance Manual MM-105.
Serial numbers 45-002 through 45-2000    Learjet 45 TR 71-1, dated April
 inclusive (commonly referred to as       28, 2009, to the Learjet 45
 ``M45'' airplanes).                      Maintenance Manual MM-104.
------------------------------------------------------------------------

Concurrent Inspections: Fluid Leakage

    (i) Concurrently with each inspection required by paragraph (h) 
of this AD, do a detailed inspection for evidence of engine oil, 
hydraulic fluid, or fuel leakage within the left engine accessory 
compartment, in accordance with the applicable maintenance manual 
section identified in Table 3 of this AD. If there is evidence of 
leakage: Before further flight, remove each plumbing clamp within 
the inspection areas specified in paragraphs (g) and (h) of this AD, 
and clean and remove all evidence of fluid leakage.

          Table 3--Maintenance Manual Sections for Inspections
------------------------------------------------------------------------
                 For--                                Use--
------------------------------------------------------------------------
Serial numbers 45-002 through 45-2000    Section 71-00-00, ``Powerplant--
 inclusive (commonly referred to as       Maintenance Practices,'' and
 ``M45'' airplanes).                      Section 71-00-01, ``Engine--
                                          Maintenance Practices,'' of
                                          the Learjet 45 Maintenance
                                          Manual MM-104, Revision 47,
                                          dated March 30, 2009.
Serial numbers 45-2001 through 45-4000   Section 71-00-01, ``Engine--
 inclusive (commonly referred to as       Maintenance Practices,'' of
 ``M40'' airplanes).                      the Learjet 40 Maintenance
                                          Manual MM-105, Revision 15,
                                          dated March 30, 2009.
------------------------------------------------------------------------

Additional Corrective Action for Fluid Leakage and Inadequate Clearance

    (j) If evidence of fluid leakage was found during any inspection 
required by paragraph (i) of this AD, or, if inadequate clearance 
was found during any action required by paragraph (g) or (h) of this 
AD: Before further flight, replace each clamp associated with the 
fluid leakage or inadequate clearance with a new clamp, in 
accordance with the applicable maintenance manual identified in 
Table 3 of this AD.

Parts Installation

    (k) As of the effective date of this AD, no person may re-
install, on any airplane, any plumbing clamp that has been removed 
in accordance with the requirements of this AD.

Alternative Methods of Compliance (AMOCs)

    (l)(1) The Manager, Wichita Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested using 
the procedures found in 14 CFR 39.19. Send information to Attn: 
James P. Galstad, Aerospace Engineer, Systems and Propulsion Branch, 
ACE-116W, FAA, Wichita Aircraft Certification Office, 1801 Airport 
Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; 
telephone (316) 946-4135; fax (316) 946-4107.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.

Material Incorporated by Reference

    (m) You must use the service information contained in Table 4 of 
this AD to do the actions required by this AD, unless the AD 
specifies otherwise.

[[Page 26291]]



                                   Table 4--Material Incorporated by Reference
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              Document                              Revision                                Date
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Bombardier Alert Service Bulletin     Original............................  December 26, 2006.
 A40-29-03.
Bombardier Alert Service Bulletin     Original............................  December 26, 2006.
 A45-29-15.
Learjet 40 Temporary Revision 71-1    Original............................  April 28, 2009.
 to the Learjet Maintenance Manual
 MM-105.
Learjet 45 Temporary Revision 71-1    Original............................  April 28, 2009.
 to the Learjet Maintenance Manual
 MM-104.
Section 71-00-00 of the Learjet 45    Revision 47.........................  March 30, 2009.
 Maintenance Manual MM-104.
Section 71-00-01 of the Learjet 45    Revision 47.........................  March 30, 2009.
 Maintenance Manual MM-104.
Section 71-00-01 of the Learjet 40    Revision 15.........................  March 30, 2009.
 Maintenance Manual MM-105.
----------------------------------------------------------------------------------------------------------------

    Learjet 40 Maintenance Manual MM-105, Revision 15, dated March 
30, 2009, has the following effective pages:

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                                                                 List of effective pages
---------------------------------------------------------------------------------------------------------------------------------------------------------
        Page title/description                     Page number(s)                        Revision number                    Date shown on page(s)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maintenance Manual Title Page........  None shown...........................  15..................................  March 30, 2009.
Maintenance Manual Revision            1-2..................................  None Shown *........................  March 30, 2009.
 Highlights.
Record of Revisions..................  1....................................  None Shown *........................  March 30, 2009.
Chapter 71 List of Effective Pages...  1....................................  None Shown *........................  March 30, 2009.
Section 71-00-01.....................  201-223..............................  None Shown *........................  December 25, 2006.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    (*Only the Maintenance Manual Title Page and Record of Revisions 
of Learjet 40 Maintenance Manual MM-104 have revision level 
information. These pages do not have this information.) Learjet 45 
Maintenance Manual MM-104, Revision 47, dated March 30, 2009, has 
the following effective pages:

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                                                                 List of effective pages
---------------------------------------------------------------------------------------------------------------------------------------------------------
        Page title/description                     Page number(s)                        Revision number                    Date shown on page(s)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maintenance Manual Title Page........  None Shown...........................  47..................................  March 30, 2009.
Maintenance Manual Revision            1-3..................................  None Shown *........................  March 30, 2009.
 Highlights.
Record of Revisions..................  1-2..................................  None Shown *........................  March 30, 2009.
Chapter 71 List of Effective Pages...  1....................................  None Shown *........................  March 30, 2009.
Section 71-00-00.....................  201..................................  None Shown *........................  April 10, 1998.
Section 71-00-01.....................  201-223..............................  None Shown *........................  April 28, 2008.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    (*Only the Maintenance Manual Title Page and Record of Revisions 
of Learjet 45 Maintenance Manual MM-104 have revision level 
information. These pages do not have this information.)
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (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; e-mail 
ac.ict@aero.bombardier.com; Internet http://www.bombardier.com.
    (3) You may review copies of the 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 or 425-227-1152.
    (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 NARA, 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 May 20, 2009.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-12518 Filed 6-1-09; 8:45 am]

BILLING CODE 4910-13-P
