Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Learjet Model 31, 31A, 35, 35A, and 60 airplanes. This proposal would require a visual inspection of the spoiler actuators to determine the serial number of the spoiler actuators; and replacement of the spoiler actuators with new actuators, if necessary. This proposal is prompted by failure of a spoiler actuator piston rod during the first production flight of a Model 60 airplane due to an incomplete heat treatment process. The actions specified by the proposed AD are intended to prevent failure of the spoiler actuator, which could result in the spoiler panel floating and inducing an uncommanded roll of the airplane.