Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Raytheon (Beech) Model 400 and 400A series airplanes. This proposed AD would require, among other actions, reviewing the airplane logbook to determine whether certain generator control unit (GCU) installation kits are installed, and replacing any incorrect GCU. This proposed AD results from reports of over-voltage conditions of the direct current (DC) starter generator. We are proposing this AD to prevent such over-voltage conditions due to the incompatibility between certain GCUs, which could result in the loss of normal electrical power, damage to some electrical components, or blown fuses during flight, and consequent unrecoverable loss of some or all essential equipment.