AD 2007-20-06

This AD becomes effective November 7, 2007.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of November 7, 2007.

You may examine the AD docket on the Internet at http://dms.dot.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.

Mike Borfitz, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 227-2677; fax (425) 227-1149.

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 16, 2007 (72 FR 12576). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

It has been revealed that the control surface balancing procedure in the Web and CD/DVD versions of the SAAB 2000 SRM (structural repair manual) Chapter 51-60-00, Control Surface Balancing Procedure is incorrect. The incorrect Calculation formula (page 1, 4 and 7) was incorporated in Revision 21 of the SRM dated April 01/05 and was distributed in 4 July 2005 on the CD/DVD issue Apr. 01/05.

In the incorrect formula, an “×” (multiplication) has been replaced with a “+” (addition) when the data was converted in the system and if this formula is followed, you may receive a result outside of the allowed tolerance.

Incorrect balance, outside the tolerance of the aileron control surface, may lead to vibrations that in [the] worst case can result in flutter.

The hard copy of the manual, SAAB 2000 SRM, is correct.

The CD/DVD dated Oct 01/05, marked “Reissue”, includes a correct SAAB SRM revision 22.

The corrective action includes identifying ailerons that have been balanced after July 4, 2005. If balanced incorrectly, they must be rebalanced.

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

Saab points out that at the time European Aviation Safety Agency (EASA) issued Emergency Airworthiness Directive 2006-0053-E, dated February 22, 2006 (the MCAI), the hard copy of the structural repair manual (SRM) was correct but the Web and CD/DVD versions had an incorrect calculation formula. At that time, the FAA did not issue an emergency AD because there were only 3 of the affected airplanes operating in the U.S. and the operators stated that they had not used the incorrect formula. The rest of the affected fleet was operating in Europe and subject to the EASA Emergency AD. SAAB AB states that this means that no affected airplane is operating with a rigging performed according to the incorrect formula. Saab recommends that we withdraw the NPRM and do not issue the AD.

We disagree with the request to withdraw the NPRM. The number of affected airplanes of U.S. registry has grown from 3 to 7 in the past year, a growth trend that could continue. We cannot be certain that all airplanes that are placed on the U.S. Register have had the ailerons balanced correctly. Issuance of this AD will ensure that airplanes will be in compliance before being permitted to operate in the U.S. We have revised the Costs of Compliance paragraph of this AD to reflect the current number of U.S.-registered airplanes. We have made no other change to the AD in this regard.

Saab requests that we change the following phrase from paragraph (e) of the NPRM: “The CD/DVD dated Oct 01/05, marked ‘Reissue’, includes a correct SAAB SRM revision 22.” Saab states that the SRM has been revised a couple of times since the MCAI was issued, and that revision 23 and higher of the SRM have the correct formula.

We acknowledge that revision 23 and higher of the SRM also have the correct formula. However, we have not revised the text in paragraph (e) of the AD because that text is simply a direct quote from the MCAI. We have not changed the AD in this regard.

We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD as proposed.

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.

Based on the service information, we estimate that this AD affects about 7 products of U.S. registry. We also estimate that it takes about 1 work-hour per product to identify ailerons that have been balanced after July 4, 2005. The average labor rate is $80 per work-hour. Based on these figures, we estimate the cost of the AD for U.S. operators to be $560, or $80 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://dms.dot.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: