AD 2009-24-22

We are adopting a new airworthiness directive (AD) for certain Learjet Model 45 airplanes. This AD requires inspecting the baggage bay door fire barrier seal for inconel mesh in the fire barrier seal material; for certain airplanes, inspecting the fiberglass doublers for presence of red Room Temperature Vulcanizing (RTV) sealant; and doing related investigative and corrective actions if necessary. This AD results from reports of incorrect external baggage door seal material and door seal sealant, as well as incorrect sealant on interior baggage panels used during manufacture of the airplane. We are issuing this AD to prevent the use of door seals and sealant that do not meet flammability requirements, which could result in an uncontrollable and undetected fire within the baggage compartment.

Final rule.

2009-24-22 Learjet Inc. (Formerly Gates Learjet Corporation): Amendment 39-16116. Docket No. FAA-2009-0719; Directorate Identifier 2009-NM-078-AD.

Effective Date

(a) This airworthiness directive (AD) is effective January 8, 2010.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Learjet Inc. Model 45 airplanes, certificated in any category, serial numbers 45-005 through 45-321 inclusive, 45-323 through 45-332 inclusive, and 45-2001 through 45- 2075 inclusive.

Subject

(d) Air Transport Association (ATA) of America Code 52: Doors, and ATA Code 25: Equipment/Furnishings.

Unsafe Condition

(e) This AD results from reports of incorrect external baggage door seal material and door seal sealant, as well as incorrect sealant on interior baggage panels used during manufacture of the airplane. The Federal Aviation Administration is issuing this AD to prevent the use of door seals and sealant that do not meet flammability requirements, whichcould result in an uncontrollable and undetected fire within the baggage compartment.

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.

Inspection of Red Room Temperature Vulcanizing (RTV) Sealant in Aft Baggage Bay

(g) For airplanes having serial numbers 45-005 through 45-314 inclusive and 45-2001 through 45-2065 inclusive: Within 300 flight hours after the effective date of this AD, do a general visual inspection of the outer surfaces of the fiberglass doublers for the presence of red RTV sealant, in accordance with the Accomplishment Instructions in Bombardier Service Bulletin 45-25-21, Revision 1, dated January 19, 2009; or 40-25-11, Revision 1, dated January 19, 2009; as applicable. If any red RTV sealant is found, before further flight, replace the sealant, in accordance with the Accomplishment Instructions in Bombardier Service Bulletin 45-25-21, Revision 1, dated January 19, 2009; or 40-25-11, Revision 1, dated January 19, 2009; as applicable.

Note 1: For the purposes of this AD, a general visual inspection is: ``A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.''

Inspection of Baggage Bay Door Fire Barrier Seal

(h) For all airplanes: Within 300 flight hours after the effective date of this AD, do a general visual inspection of the baggage bay door fire barrier seal for the presence of metal inconel mesh in the material, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions in Bombardier Service Bulletin 45-52-16, Revision 1, dated July 21, 2008; or 40-52-07, Revision 1, dated July 21, 2008; as applicable. Do all applicable related investigative and corrective actions before further flight in accordance with the Accomplishment Instructions in Bombardier Service Bulletin 45-52-16, Revision 1, dated July 21, 2008; or 40-52-07, Revision 1, dated July 21, 2008; as applicable.

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: William Griffith, Aerospace Engineer, Airframe Branch, ACE- 118W, FAA, Wichita ACO, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 946-4116; 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

(j) You must use the service information contained in Table 1 of this AD to do the actions required by this AD, unless the AD specifies otherwise.
(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.

Table 1--Material Incorporated by Reference

Service Bulletin
Revision
Date
Bombardier Service Bulletin 40-25-11
1
January 19, 2009
Bombardier Service Bulletin 45-25-21
1
January 19, 2009
Bombardier Service Bulletin 40-52-07
1
July 21, 2008
Bombardier Service Bulletin 45-52-16
1
July 21, 2008

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Learjet Inc. Model 45 airplanes. That NPRM was published in the Federal Register on August 27, 2009 (74 FR 43645). That NPRM proposed to require inspecting the baggage bay door fire barrier seal for inconel mesh in the fire barrier seal material; for certain airplanes, inspecting the fiberglass doublers for presence of red Room Temperature Vulcanizing (RTV) sealant; and doing related investigative and corrective actions if necessary.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

We reviewed the relevant data and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

We estimate that thisAD affects 256 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this AD.

Estimated Costs

Action
Work hours
Average labor rate per hour
Cost per product
Number of U.S.-registered airplanes
Fleet cost
Inspection and modification of red RTV sealant
10
$80
$800
Up to 256
Up to $204,800
Inspection and modification of fire barrier seal
6
$80
$480
Up to 256
Up to $122,880

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

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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: