What was found
CREW EXPERIENCED AN UNSCHEDULED PROP FEATHER ON ENGINE NR 1 DURING TAKEOFF. MEMORY ITEMS PERFORMED. QRH WORK CARRIED OUT. CABIN AND PASSENGERS INFORMED ACCORDINGLY, FOLLOWED BY NORMAL AND UNEVENTFUL RELANDING. AFTER NORMAL DISEMBARKATION OF PASSENGERS A/C WAS HANDED OVER TO MAINTENANCE. TROUBLESHOOTING AFTER THE EVENT HAS LED TO FAULTY NR 1 TSCU. THE UNIT GENERATED AN UNCOMMANDED `AUTOFEATHER` MESSAGE, ALTHOUGH THERE WERE NO CONDITIONS FOR PROP FEATHERING. THE FAULT WAS DUPLICATED ON GROUND. AFTER PUSHING THE `ARM` BUTTON AND SETTING THE TOGGLE SWITCHES TO `TEST`, THE PUMP STARTED RUNNING. TSCU WAS CHANGED, ALL TESTS CONDUCTED AND PASSED. CHECK FLIGHT PERFORMED, NO DISCREPANCIES.