AD 2008-26-09

This AD becomes effective January 28, 2009.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of January 28, 2009.

You may examine the AD docket on the Internet at http://www.regulations.gov or in person at the U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.

Rocco Viselli, 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) 228-7331; fax (516) 794-5531.

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 September 17, 2008 (73 FR 53773). 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 CL-600-2B19 aircraft fuel system against the new 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 assessed using Transport Canada Policy Letter No. 525-001 to determine if mandatory corrective action is required.

The assessment showed that insufficient electrical bonding between the refuel/defuel shutoff valves and the aircraft structure could occur due to the presence of a non-conductive gasket (Gask-O-Seal). In addition, it was also determined that the presence of an anodic coating on the shutoff valve electrical conduit connection fitting could affect electrical bonding. The above conditions, if not corrected, could result in arcing and potential ignition source inside the fuel tank during lightning strikes and consequent fuel tank explosion.

To correct the unsafe condition, this directive mandates the modification of the [shutoff valves in the] refuel/defuel system.

You may obtain further information by examining the MCAI in the AD docket.

We gave the public the opportunity to participate in developing this AD. We considered the comments received.

Air Wisconsin Airlines Corporation (Air Wisconsin) requests that we revise paragraph (f)(1) of the NPRM to refer to Bombardier Service Bulletin 601R-28-053, Revision D, dated August 20, 2008.

We agree to change paragraph (f)(1) of this AD to refer to Bombardier Service Bulletin 601R-28-053, Revision D. We referred to Bombardier Service Bulletin 601R-28-053, Revision C, dated March 14, 2006, as the appropriate source of service information for accomplishing the actions in the NPRM. We have reviewed Bombardier Service Bulletin 601R-28-053, Revision D, and find that it is essentially the same as the prior revisions referenced in the NPRM; it differs from Bombardier Service Bulletin 601R-28-053, Revision C, by correcting a statement in the Description paragraph, removing a part number and the Interchangeability Code from the Disposition of Parts table, and having small editorial changes that do not affect its technical content. We have changed paragraph (f)(1) of this AD accordingly, and added credit for actions done according to Bombardier Service Bulletin 601R-28-053, Revision C, to paragraph (f)(2) of this AD.

AWAC requests that we supersede AD 2006-02-10 with this AD, as it addresses airplanes modified by Bombardier Service Bulletin 601R-28-053, dated July 12, 2004.

We disagree with this request, as this AD applies to different airplanes than AD 2006-02-10, amendment 39-14462 (71 FR 4040, January 25, 2006). That AD applies to certain airplanes modified by Bombardier Service Bulletin 601R-28-053, dated July 12, 2004, and other airplanes having serial numbers 7940 through 7988. This AD does not apply to those airplanes. We have not changed the AD in this regard.

AWAC requests that airplanes modified according to AD 2006-02-10 be approved as complying with the proposed AD.

We disagree with this request. As mentioned in the prior response, AD 2006-02-10 applies to different airplanes from those specified in this AD, and are affected by different service information. Further, those airplanes are not subject to the requirements of this AD. We have not changed the AD in this regard.

AWAC requests that we give credit for actions done according to Bombardier Service Bulletin 601R-28-053, dated July 12, 2004; Revision A, dated April 21, 2005; Revision B, dated September 15, 2005; and Revision C, dated March 14, 2006. AWAC requests that we also give credit for Bombardier Service Bulletin A601R-28-064, dated April 21, 2005; Revision A, dated September 15, 2005; Revision B, dated March 14, 2006; and Revision C, dated April 19, 2006.

We partially agree with this request. Credit for actions done according to Bombardier Service Bulletin 601R-28-053, Revisions A and B, appears in paragraph (f)(2) of the AD; and, as mentioned above, we are adding credit for Bombardier Service Bulletin 601R-28-053, Revision C, to that paragraph. Airplanes on which Bombardier Service Bulletin 601R-28-053, dated July 12, 2004, has been done are not subject to this AD, so we have not given credit in the AD for Bombardier Service Bulletin 601R-28-053, dated July 12, 2004. Bombardier Service Bulletin A601R-28-064 is not a method of compliance for this AD, so no credit is given for it in this AD.

AWAC states that there is no discussion of warranty consideration in the service bulletin; we infer that AWAC requests warranty information in the Costs of Compliance section of the AD.

We disagree with this request. Warranty information is provided by the manufacturer, and we have not changed the AD in this regard.

Based on new information, we have reduced the estimated number of products in the Costs of Compliance section of the NPRM from 970 to 677. The estimated cost per product stays the same, while the estimated cost of this AD to U.S. operators is reduced to $2,112,917.

We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We determined that these changes will not increase the economic burden on any operator or increase the scope of the AD.

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.

We estimate that this AD will affect about 677 products of U.S. registry. We also estimate that it will take about 26 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Required parts will cost about $1,041 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these parts. 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 AD to the U.S. operators to be $2,112,917, or $3,121 per product.

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.

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.

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.

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

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

2. The FAA amends § 39.13 by adding the following new AD: