AD 2008-02-06

This AD becomes effective on February 26, 2008.

On February 26, 2008, the Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD.

To get the service information identified in this AD, contact GARMIN International Inc., 1200 East 151st Street, Olathe, KS 66062; telephone: 913-397-8200; fax: 913-397-8282.

To view the AD docket, go to U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, or on the Internet at http://www.regulations.gov. The docket number is FAA-2007-28730; Directorate Identifier 2007-CE-063-AD.

Roger A. Souter, Aerospace Engineer, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: 316-946-4134; fax: 316-946-4107; e-mail address: roger.souter@faa.gov.

On August 14, 2007, we issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain GARMIN International (GARMIN) GSM 85 servo gearbox units that are installed on airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on August 21, 2007 (72 FR 46582). The NPRM proposed to require you to inspect the GSM 85 servo gearbox for foreign object debris and return the unit to the manufacturer for replacement if you find debris.

We provided the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal and FAA's response to each comment:

GARMIN states that using the phrase “excessive manual force” in the NPRM implies that the flight crew may not be able to control the airplane if the servo gearbox jams because of loose foreign object debris inside the gear-assembly housing.

GARMIN agrees that more than typical or usual force may be necessary to overcome the slip clutch in the servo, but it is within the capability of the pilot to control the airplane.

GARMIN requests that the phrase “excessive manual force” be replaced with “sufficient control force to override the servo gearbox slip clutch.”

We partially agree with GARMIN. We will change the final rule AD action to reflect that jamming could lead to the pilot having to apply sufficient control force to override the servo gearbox slip clutch in order to control the airplane.

Cessna Aircraft Company (Cessna) has issued Service Bulletin SB07-22-01, dated June 4, 2007, to transmit GARMIN International, Inc. Service Bulletin No. 0713, Revision C, dated May 29, 2007.

Cessna requests that their service bulletin be incorporated as a means for complying with this AD.

We agree with Cessna and will change the final rule AD action to incorporate this change.

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for the changes previously discussed and minor editorial corrections. We have determined that these minor corrections:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

We estimate that this AD affects 900 airplanes in the U.S. registry.

We estimate the following costs to do the inspection:

For airplanes that will need to replace the GSM 85 servo gearbox based on the results of the inspection, we estimate the following costs to set the torque value of the slip-clutch breakaway required for installation. We have no way of determining the number of airplanes that will need this replacement:

Warranty credit will be given to the extent specified in the service information.

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 AD.

We have 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 that 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 summary of the costs to comply with this AD (and other information as included in the Regulatory Evaluation) and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “Docket No. FAA-2007-28730; Directorate Identifier 2007-CE-063-AD” in your request.

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

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

2. FAA amends § 39.13 by adding a new AD to read as follows: