B757 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Total 8911
Aircraft Equipment Problem Less Severe
Flight Crew FLC Overrode Automation; Flight Crew Returned To Departure Airport; Flight Crew Overcame Equipment Problem; Flight Crew Landed As Precaution
Aircraft
Aircraft was worked on for a multitude of maintenance issues. Systems were tested and deemed repaired. All previous issues that were worked on returned during climbout at approximately 1;500 feet. The following EICAS cautions appeared. L ENG EEC; R ENG EEC; ALT DISAGREE; IAS DISAGREE; RUDDER RATIO; MACH/SPD TRIM along with erroneous airspeed and altitude indications on the First Officer's panel. Control was transferred to the Captain as it was determined that his indications were correct. [ATC was advised]; all appropriate checklists completed; Dispatch contacted; cabin crew and passengers briefed landing data obtained and FMC set up for a return to [departure airport]. The subsequent approach and landing to Runway XXR was uneventful.
Immediately after takeoff; the FO (First Officer) noticed an airspeed fluctuation followed immediately by ALT DISAGREE; IAS DISAGREE; L/R ENG EEC'S; MACH/SPEED TRIM; RUDDER RATIO and AUTOTHROT DISC. These were the exact same issues the aircraft had experienced on the inbound flight. Maintenance had narrowed it down to the FO'S ADC. Since we knew my (Captain's) instruments were accurate; I assumed control. We ran through applicable checklists; briefed the FAs (Flight Attendants) and passengers; notified company through radio calls and ACARS and returned to the airport without incident.
B757 flight crew reported that the First Officer's flight instruments started to malfunction and disagreed with the Captain's side causing a return to their departure airport.