AD 2008-09-24

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Bombardier Aerospace has completed a system safety review of the aircraft fuel system against fuel tank safety standards introduced in Chapter 525 of the Airworthiness Manual through Notice of Proposed Amendment (NPA) 2002-043. The identified non-compliances were then assessed using Transport Canada Policy Letter No. 525-001, to determine if mandatory corrective action is required.

The assessment showed that it is necessary to introduce Critical Design Configuration Control Limitations (CDCCL), in order to preserve critical fuel tank system ignition source prevention features during configuration changes such as modifications and repairs, or duringmaintenance actions. Failure to preserve critical fuel tank system ignition source prevention features could result in a fuel tank explosion. * * *

We are issuing this AD to require actions to correct the unsafe condition on these products.

Final rule.

2008-09-24 Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 39-15505. Docket No. FAA-2008-0267; Directorate Identifier 2008-NM- 030-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective June 6, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all Bombardier Model DHC-8-400, DHC-8- 401, and DHC-8-402 airplanes, certificated in any category, all serial numbers.

Subject

(d) Air Transport Association (ATA) of America Code 28: Fuel.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

Bombardier Aerospace has completed a system safety review of the aircraft fuel system against fuel tank safety standards introduced in Chapter 525 of the Airworthiness Manual through Notice of Proposed Amendment (NPA) 2002-043. The identified non-compliances were then assessed using Transport Canada Policy Letter No. 525-001, to determine if mandatory corrective action is required.

The assessment showed that it is necessary to introduce Critical Design Configuration Control Limitations (CDCCL), in order to preserve critical fuel tank system ignition source prevention features during configuration changes such as modifications and repairs, or during maintenance actions. Failure to preserve critical fuel tank system ignition source prevention features could result in a fuel tank explosion. Revisions have been made to Part 2 "Airworthiness Limitations Items" of the Maintenance Requirements Manual of the affected models to introduce the required CDCCL.

The corrective action is revising the Airworthiness Limitations Section (ALS) of the Instructions for Continued Airworthiness to include the CDCCL data.

Actions and Compliance

(f) Unless already done, do the following actions.

(1) For all airplanes: Within 60 days after the effective date of this AD, or before December 16, 2008, whichever occurs first, revise the ALS of the Instructions for Continued Airworthiness to incorporate the CDCCLs specified in Dash 8 Q400 (Bombardier) Temporary Revisions (TRs) ALI-55, dated April 19, 2006; and ALI-56, dated April 19, 2006; to Part 2, "Airworthiness Limitations Items," of the Bombardier Dash 8 Q400 Maintenance Requirements Manual (MRM) PSM 1-84-7.

Note 1: The actions required by paragraph (f)(1) of this AD may be done by inserting a copy of the applicable TR into the maintenance requirements manual. When the TR has been included in the general revision of the maintenance program, the general revision may be inserted into the maintenance requirements manual, provided the relevant information in the general revision is identical to that in the applicable TR, and the temporary revision may be removed.

(2) After accomplishing the actions specified in paragraph (f)(1) of this AD, no alternative CDCCLs may be used unless the CDCCLs are part of a later revision of Part 2, Revision 4, dated October 30, 2003, of the Bombardier Dash 8 Q400 MRM PSM 1-84-7, Revision 4, that is approved by the Manager, New York Aircraft Certification Office (ACO), FAA, or Transport Canada Civil Aviation (or its delegated agent); or unless the CDCCLs are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (g)(1) of this AD.

FAA AD Differences

Note 2: This AD differs from the MCAI and/or service information as follows: No differences.

Other FAA AD Provisions

(g) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, New York 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: Richard Fiesel, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone (516) 228-7304; fax (516) 794- 5531.Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120- 0056.

Related Information

(h) Refer to MCAI Canadian Airworthiness Directive CF-2008-06, dated January 15, 2008; and Bombardier TRsALI-55 and ALI-56, both dated April 19, 2006; for related information.

Material Incorporated by Reference

(i) You must use Dash 8 Q400 (Bombardier) Temporary Revision ALI-55, dated April 19, 2006, to Part 2, "Airworthiness Limitations Items," of the Bombardier Dash 8 Q400 Maintenance Requirements Manual PSM 1-84-7; and Dash 8 Q400 (Bombardier) Temporary Revision ALI-56, dated April 19, 2006, to Part 2, "Airworthiness Limitations Items," of the Bombardier Dash 8 Q400 Maintenance Requirements Manual PSM 1-84-7; 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 Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada.

(3) You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 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/cfr/ibr- locations.html.

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 March 11, 2008 (73 FR 12907). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

Bombardier Aerospace has completed a system safety review of the aircraft fuel system against fuel tank safety standards introduced in Chapter 525 of the Airworthiness Manual through Notice of Proposed Amendment (NPA) 2002-043. The identified non-compliances were then assessed using Transport Canada Policy Letter No. 525-001, to determine if mandatory corrective action is required.

The assessment showed that it is necessary to introduce Critical Design Configuration Control Limitations (CDCCL), in order to preserve critical fuel tank system ignition source prevention features during configuration changes such as modificationsand repairs, or during maintenance actions. Failure to preserve critical fuel tank system ignition source prevention features could result in a fuel tank explosion. Revisions have been made to Part 2 "Airworthiness Limitations Items" of the Maintenance Requirements Manual of the affected models to introduce the required CDCCL.

The corrective action is revising the Airworthiness Limitations Section of the Instructions for Continued Airworthiness to include the CDCCL data. You may obtain further information by examining the MCAI in the AD docket.

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 available data and determined that air safety and the public interest require adopting the AD as proposed.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have required different actions in this AD from those in the MCAI in order to follow our FAA policies. Any such differences are highlighted in a NOTE within the AD.

Costs of Compliance

We estimate that this AD will affect about 45 products of U.S. registry. We also estimate that it will take about 1 work-hour per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $3,600, or $80 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 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 this AD:

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.

We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

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: