Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to all British Aerospace (Jetstream) Model 4101 airplanes. This action requires repetitive functional testing of the main entrance door, cleaning and lubricating of the ``speed'' lock and ``G'' lock systems, and repair, if necessary. This amendment is prompted by reports of flight crews and ground crews being unable to open the main entrance door. The actions specified in this AD are intended to prevent inability of the main entrance door to open, which could delay or impede passengers exiting the airplane, or rescue personnel from entering the airplane during an emergency.