What was found
(CAN) CREW DID RAM AIR TURBINE DROP TEST IN FLIGHT AND AFTER RAT DEPLOYED, A/C LOST ALL COCKPIT INDICATION (INCLUDING GEAR INDICATIONS) ONLY STANDBY INSTRUMENTS WERE FUNCTIONING, RAT HANDLE WAS STOWED IN THE ALLOTTED TIME, CREW TRIED TRANSFER OVERRIDE WITH SAME ISSUE, NUMEROUS CIRCUIT BREAKERS WERE POPPED(IRU 1, FDR AC, ADC 1, STALL PROTECTION LEFT CHANNEL, VHF COM 1, OVERHEAD PANEL LIGHTS). CREW DECLARED EMERGENCY. TROUBLESHOOTING IS IN PROGRESS. THE EMERGENCY GENERATOR CONTROL UNIT (GCU) AND PARTICULARLY, THE GENERATOR CONTACTOR DRIVER(GCD) AND VOLTAGE REGULATOR CIRCUIT INSIDE THE GCU WOULD HAVE CAUSED THIS ISSUE. TROUBLESHOOTING AND INVESTIGATION IS ONGOING. (TC# 20190530003)