What was found
DURING APPROACH TO BUF CREW RECEIVED A FLAP SYSTEM FAILURE MESSAGE WHEN FLAPS WERE A ZERO DEGREES AND SELECTED TO 8 DEGREES. CREW PERFORMED MISSED APPROACH TO BUF AND DETERMINED RUNWAY LENGTH WAS NOT ADEQUATE. FLIGHT 7802 THEN DIVERTED TO IAD AND PERFORMED A ZERO FLAP LANDING. FLIGHT LANDED UNEVENTFULLY AND PASSENGERS DEPLANED NORMALLY. THE FLAP POWER DRIVE UNIT WAS FOUND FAULTY AND REPLACED. A SATISFACTORY OPERATIONAL CHECK WAS PERFORMED AND AIRCRAFT WAS RETURNED TO SERVICE.