Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to various General Dynamics (Convair) airplanes. This proposal would require revising the Airplane Flight Manual to require that the flight crew limit the flap settings during certain icing conditions and air temperatures. This proposal is prompted by reports indicating that incidents involving uncommanded pitch excursions have occurred due to ice contaminated tailplane stall (ICTS) that occurred during or following flight in icing conditions. If flap settings are increased for landing when ICTS is present, elevator control could be affected adversely and the airplane could descend uncontrollably. The actions specified by the proposed AD are intended to ensure that the flight crew is advised of the potential hazard related to increasing the flap settings when ICTS is present, and the procedures necessary to address it.