What was found
DURING TAKEOFF, SPEED TAPE INDICATIONS ERRATIC, SR WAS ABSENT, AFTER SLATS RETRACT AIRSPEED LIMITED TO 260. AT 2000 FEET AP 1 SELECTED, INDICATIONS ERRATIC, SELECTED AP 2 INDICATIONS OK, THEN FD 1 FAILED. SELECTED FLT DIR CAPTAIN'S ON 2. ALSO STBY INDICATOR FALLING OFF. DURING APPROACH STBY PFD NORMAL. AIR TURN BACK AFTER CONSULTATION WITH GOC. PER CREW DEBRIEF SLAT RETRACT SPEED & FLAP RETRACT SPEED BECAME ERRATIC ON CAPTAIN`S PFD, SPEEDS WERE STEADY & CORRECT ON FIRST OFFICER`S SIDE & IN FMC. R & R NR1 FCC IAW AMM 22-01-03-4. RTS TEST FAILED, COULD NOT COMPLETE RTS DUE TO ROB FLAP POSITION ON MEL27-50 7734. CAPTAIN’S FLT DIR OPERATIONS CHECKED NORMAL IAW FIM 34-24-01. R & R SAI IAW AMM 34-28-01-2, OPERATIONS CHECKED NORMAL. CANNOT COMPLETE SIGN OFF UNTIL ROB FLAP POSITION XMTR IS REPLACED.