AD 98-21-25 63 FR 55325 Active

This amendment adopts a new airworthiness directive (AD) that applies to certain British Aerospace Jetstream Models 3101 and 3201 airplanes that are equipped with the ground inhibit function (Modification JM7813A (SB 27-JM7813A) or JM7813B). This AD requires removing the ground inhibit time delay and the ground test relay from the stall warning and protection system and rewiring part of the stall warning and protection system to assure that system reliance is maintained after relay removal. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by this AD are intended to prevent failure of the ground inhibit relay while it is in the energized position caused by the current design, which could result in failure of the stall warning system and possible loss of control of the airplane in certain situations if the crew was not aware that the system had failed.