SAIB CE-03-57 —

No. CE-03-57 September 22, 2003 We post SAIBs on the internet at www.airweb.faa.gov This is information only. Recommendations are not mandatory.

Introduction This Special Airworthiness Information Bulletin (SAIB) informs you, a registered owner or operator of Air Tractor Inc AT-300, AT-400, AT-500, AT-600, and AT-800 series airplanes, of the potential for cracks or corrosion on the Horizontal Stabilizer Attaching Pedestal. The FAA has received reports of cracked and corroded pedestals being found on various Air Tractor models.

Background Air Tractor originally issued Snow Engineering Service Letter (SESL) #180 in response to reports of cracked and corroded horizontal stabilizer attaching pedestals. The pedestal is the welded fitting bolted to the upper longerons in the fuselage airframe aft section. The right and left hand horizontal stabilizer aft-spar fittings and the elevator control arm attach to the pedestal.

Air Tractor has redesigned the pedestal for longer service life. Air Tractor has now issued SESL #180A to provide inspection requirements for the old vs. new pedestal designs (100 hours TIS and annually, respectively), and to show installation of washer plates (radius blocks) required for the new design. Refer to the Service Letter for aircraft model and serial number effectivity and replacement pedestal part numbers.

Recommendation The FAA strongly recommends that you, starting at 2000 hours TIS, inspect the pedestal mount in accordance with SESL #180A. Any mounts found cracked or corroded should be replaced before continued flight in accordance with the instructions in the Service Letter. In addition, the older style mounts should be replaced for improved reliability and extended inspection requirements. These actions will help insure the continued airworthiness of your airplane.

For Further Information Contact Andrew McAnaul, Aerospace Engineer, FAA Ft. Worth ACO, ASW-150, 2601 Meacham Blvd, Fort Worth, TX 76193; phone: (817) 222-5156; fax: (817) 222-5960; e-mail: [email protected]

You can obtain copies of Service Letter #180A from the Air Tractor Customer Service Department at (940) 564-5616, or through your local Air Tractor Dealer.