AD Superseded for AT-802 Air Tankers - National Agricultural Aviation Association

The FAA is superseding Airworthiness Directive (AD) 2024-16-06, which applied to all Air Tractor AT-802 and AT-802A airplanes with Wipaire, Inc. Supplemental Type Certificate (STC) No. SA01795CH installed. AD 2024-16-06 required repetitively inspecting the left and right, forward and rear, horizontal stabilizer spars for cracks, replacing any horizontal stabilizer spar found cracked or damaged, installing bathtub fittings, and reporting inspection results to the FAA.

Since the FAA issued AD 2024-16-06, additional reports of cracking have been reported in a nearby, related location where the vertical fin structural support brace mounts to the horizontal stabilizer spar.

This superseding AD retains the 110-hour Time in Service (TIS) interval inspections of the horizontal stabilizer spars, and 300-hour TIS installation of bathtub fittings from AD 2024-16-06. It also retains the subsequent 110-hour TIS interval inspections after installation of bathtub fittings but directs use of update service material for these inspections, namely Wipaire Service Letter 253, Revision H, dated July 27, 2026.

This superseding AD adds a required 50-hour TIS repetitive inspection of the right and left horizontal stabilizer spars at the strut brace mount locations for cracks in accordance with Wipaire Service Letter 277, Revision C, dated July 27, 2026. If any crack is found, before further flight, replace the horizontal stabilizer spar.

The FAA considers this AD to be an interim action and is evaluating the need to establish a life limit (potentially as low as 2,000 hours TIS) on the horizontal stabilizer spars to mitigate this issue long term.

AD 2026-16-12 is effective August 31, 2026.