The original AD, which “requires repetitively inspecting the stabilator tip tube and weight assemblies for cracks, inspecting for missing rivets and screws, replacing the forward rib/horn assemblies, and reinforcing the mounting,” was issued to prevent stabilator-structure weakening and possible loss of control after routine inspections turned up cracks on stabilators and “abnormal trim tab horn bushing wear.”
However, as a result of a subsequent change to the stabilator design, airplanes starting with serial number 27-7954122 “are not subject to the unsafe condition addressed by AD 78-02-03,” a change that would be reflected in the new AD, the FAA said in its proposed revision, published September 16.
The list of affected aircraft should also be adjusted in accordance with Piper service bulletin SB 540B—a February 2021 revision of the service bulletin that covered the stabilator tip tube and the weight assembly inspections, the FAA said.
Members may submit formal comments on the proposed AD until November 1 online or by mail 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. Please include “Docket Number FAA-2020-1006; Project Identifier 2019-CE-047-AD” at the beginning of your comments.