Document ID: FAA-2010-0676-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Learjet Inc. Model 45 Airplanes
Posted Date: 2010-07-07T04:00Z

[Federal Register Volume 75, Number 129 (Wednesday, July 7, 2010)]
[Proposed Rules]
[Pages 38941-38943]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-16514]

 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 75, No. 129 / Wednesday, July 7, 2010 / 
Proposed Rules  

[[Page 38941]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0676; Directorate Identifier 2010-NM-095-AD]
RIN 2120-AA64

Airworthiness Directives; Learjet Inc. Model 45 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Learjet Inc. Model 45 airplanes. This proposed AD would require 
replacing aluminum fire extinguisher discharge tubes with new, improved 
tubes; checking the fire extinguisher container for certain serial 
numbers; replacing fire extinguisher containers that have affected 
serial numbers; inspecting the pressure indicator on certain fire 
extinguisher containers for discrepancies; and performing corrective 
action if necessary. This proposed AD results from a report of 
accidental discharge of a fire extinguisher container and damage to an 
aluminum discharge tube. Investigation revealed that following the 
discharge an inaccurate pressure indication, due to the indicator dial 
being incorrectly staked, showed that the container was fully charged. 
We are proposing this AD to prevent inaccurate pressure readings and 
subsequent damage to the discharge tubes during operation, which could 
result in failure of the fire extinguisher system and an uncontained 
fire in an emergency situation.

DATES: We must receive comments on this proposed AD by August 23, 2010.

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 proposed 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.

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 (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 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:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-0676; 
Directorate Identifier 2010-NM-095-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 received a report of accidental discharge of a fire extinguisher 
container and damage to an aluminum discharge tube. Investigation 
revealed that following the discharge an inaccurate pressure 
indication, due to the indicator dial being incorrectly staked, showed 
that the container was fully charged. Inaccurate pressure readings, and 
subsequent damage to the discharge tubes during operation, could result 
in failure of the fire extinguisher system and an uncontained fire in 
an emergency situation.

Relevant Service Information

    We have reviewed Bombardier Service Bulletins 40-26-05 and 45-26-9, 
both Revision 2, both dated May 4, 2009. The service information 
describes procedures for the following:
     For all airplanes: Installing new o-rings and stainless 
steel fire extinguisher discharge tubes and inspect the serial numbers 
on the fire extinguisher containers to determine whether any serial 
number is specified in Table 1 of the Accomplishment Instructions of 
the applicable service bulletin.
     For airplanes on which no serial number is specified in 
Table 1: Inspecting the pressure indicator on the fire extinguisher 
container to ensure that the indicator dial is not loose and is staked 
in the right location, and do a weight check of the fire extinguisher 
container. If the indicator is loose or not staked in the right 
location or if the weight check for any container fails, replacing the 
affected container.
     For airplanes on which any serial number is specified in 
Table 1: Replacing the affected fire extinguisher container, and do a 
weight check of the replaced containers. If the weight check for any 
replacement container fails, replacing the affected container.

[[Page 38942]]

FAA's Determination and Requirements of This Proposed AD

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

Costs of Compliance

    We estimate that this proposed AD would affect 322 airplanes of 
U.S. registry. We also estimate that it would take 5 work-hours per 
product to comply with this proposed AD. The average labor rate is $85 
per work-hour. Required parts cost would be minimal. Where the service 
information lists required parts costs that are covered under warranty, 
we have assumed that there will be no charge for these costs. As we do 
not control warranty coverage for affected parties, some parties may 
incur costs higher than estimated here. Based on these figures, we 
estimate the cost of this proposed AD to the U.S. operators to be 
$136,850, or $425 per product.

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), 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.

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:

    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 AD:

Learjet Inc: Docket No. FAA-2010-0676; Directorate Identifier 2010-
NM-095-AD.

Comments Due Date

    (a) We must receive comments by August 23, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Learjet Inc. Model 45 airplanes, 
certificated in any category; as identified in Bombardier Service 
Bulletins 40-26-05 and 45-26-9, both Revision 2, both dated May 4, 
2009.

Subject

    (d) Air Transport Association (ATA) of America Code 26: Fire 
protection.

Unsafe Condition

    (e) This AD results from a report of accidental discharge of a 
fire extinguisher container and damage to an aluminum discharge 
tube. Investigation revealed that following the discharge an 
inaccurate pressure indication, due to the indicator dial being 
incorrectly staked, showed that the container was fully charged. The 
Federal Aviation Administration is issuing this AD to prevent 
inaccurate pressure readings and subsequent damage to the discharge 
tubes during operation, which could result in failure of the fire 
extinguisher system and an uncontained fire in an emergency 
situation.

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.

Replacement, Check, Inspection, Corrective Action

    (g) Within 12 months after the effective date of this AD: 
Replace the aluminum fire extinguisher discharge tubes with new, 
improved stainless steel tubes; check the fire extinguisher 
container for any serial number specified in Table 1 of Bombardier 
Service Bulletins 40-26-05 or 45-26-9, both Revision 2, both dated 
May 4, 2009; as applicable; replace any containers that have 
affected serial numbers, do a weight check of all containers, 
including the replacement container, if applicable; and inspect the 
pressure indicator on the containers for discrepancies, by doing all 
applicable actions in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletins 40-26-05 or 45-26-9, 
both Revision 2, both dated May 4, 2009; as applicable. If any 
discrepancy is found, replace the container before further flight in 
accordance with the Accomplishment Instructions of Bombardier 
Service Bulletins 40-26-05 or 45-26-9, both Revision 2, both dated 
May 4, 2009; as applicable.
    (h) Actions done before the effective date of this AD in 
accordance with the applicable service information listed in Table 1 
of this AD are acceptable for compliance with the corresponding 
requirements in paragraph (g) of this AD.

                                       Table 1--Credit Service Information
----------------------------------------------------------------------------------------------------------------
                                    Bombardier
    Affected serial numbers--         service               Revision--                        Dated--
                                    bulletin--
----------------------------------------------------------------------------------------------------------------
For Model 45 airplanes having           40-26-05  Basic Issue...................  November 24, 2008.
 serial numbers 2001 through
 2114, inclusive.
For Model 45 airplanes having           40-26-05  1.............................  December 22, 2008.
 serial numbers 2001 through
 2114, inclusive.
For Model 45 airplanes having     45[dash]26[das  Basic Issue...................  November 24, 2008.
 serial numbers 006 through 383,             h]9
 inclusive.

[[Page 38943]]

 
For Model 45 airplanes having     45[dash]26[das  1.............................  December 22, 2008.
 serial numbers 006 through 383,             h]9
 inclusive.
----------------------------------------------------------------------------------------------------------------

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. Send information to 
ATTN: James 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.

    Issued in Renton, Washington, on June 29, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-16514 Filed 7-6-10; 8:45 am]
BILLING CODE 4910-13-P