What was found
FLIGHT 5564 - RECEIVED A FLAP FAIL CAUTION MESSAGE AT 20 DEGREES AFTER TAKEOFF FROM BWI, FLIGHT RETURNED TO THE FIELD. COMPLIED WITH AD 09-20-01 FLAP CAUTION MESSAGE -FIRST EVENT- MAINTENANCE ACTION, PARAGRAPH (B) 1, 2, 3, (A, B, C AND E). FLAP SYSTEM WAS RESET WITH NO FURTHER FLAP CAUTION MESSAGES.