What was found
CREW REPORTED RED AIRSPEED TAPE WOULD NOT DISAPPEAR AFTER FLAPS RETRACTED. CREW RETURNED TO FIELD AND LANDED SAFELY. MAINTENANCE IS CURRENTLY WORKING ON REPAIR OF ACFT. TROUBLESHOT AND FOUND RED AIRSPEED TAPE TO BE SHOWING DUE TO NR 2 SFECU UNABLE TO LOCATE FLAP POSITION FROM 1 TO 0 DEGREES. SWAPPED NR 1 AND NR 2 DCU’S FOR T/S IAW AMM 31-41-04-000/400-801-A01, OPS CHECK GOOD. DCU’S RETURNED TO ORIGINAL CONFIGURATION, OPS CHECK GOOD. R & R NR 1 SFECU IAW AMM 27-51-05-000/400-801, OPS CHECK GOOD.