EMB-145 flight crew reported pitch trim failure on initial climb and return to departure airport.
Synopsis
EMB-145 flight crew reported pitch trim failure on initial climb and return to departure airport.
Narrative
After a normal takeoff and initial climb; while climbing through approximately 10;000 feet; an EICAS message PITCH TRIM MAIN INOP" appeared. At the time; the Captain was Pilot Flying and I was Pilot Monitoring. The autopilot was engaged and flight controls initially felt normal.The Captain transferred control of the aircraft to me while he referenced the QRH. He verbally confirmed the correct QRH page and title with me. While the QRH was being reviewed; additional EICAS messages appeared; including "PITCH TRIM BACKUP INOP" and "AUTO TRIM FAIL."Shortly thereafter; the autopilot disconnected on its own. I pressed the autopilot quick disconnect to silence the aural warning. At that time; I noticed increased control forces were required to maintain the flight director; and the aircraft momentarily deviated slightly above the command bars. The Captain then took control of the aircraft and handed me the QRH so I could continue the checklist from where he left off.As I continued the QRH; the additional EICAS messages cleared; leaving only "PITCH TRIM MAIN INOP" displayed. Following the QRH; I confirmed with the Captain the correct guarded switch and then selected the Pitch Trim Main System Cutout as directed by the QRH. While the Captain was flying; I observed him attempt to use the backup trim switch; which did not appear to provide the expected response.The Captain instructed me to request priority handling and request a return to ZZZ. I notified ATC of the request; provided souls on board; fuel remaining; and the nature of the issue. ATC asked if additional equipment would be needed; and the Captain requested that they be standing by as a precaution.During the return; I programmed the FMS; sent an ACARS message to Dispatch advising of the situation for which they acknowledged; and obtained landing distance data for maximum landing weight for Runways XX and XY. I handled all heading and altitude selections on the flight guidance panel while the Captain hand-flew the aircraft for the remainder of the flight.The Captain noted that the aircraft would be landing overweight and requested delaying vectors to burn fuel. He elected to extend Flaps 9 to aid fuel burn and controllability; followed later by Flaps 22; which further improved handling. We completed the landing checklist; conducted an approach briefing; and cross-checked that all required items were completed.Once sufficient fuel had been burned; the Captain asked me to advise ATC that we were ready for the approach and to request a long final for Runway XX. The Captain briefed that he might require assistance with the controls if the approach became difficult. The approach remained stable and uneventful; and no assistance with the controls was required.Landing was normal; and we exited the runway without issue and taxied to Gate XX. At the gate; the Captain contacted Maintenance and wrote up the discrepancy. Passengers deplaned normally with no reported issues or complaints. Maintenance troubleshooting later determined that a malfunctioning computer required replacement."
Second reporter narrative
I was the Pilot Flying ; and aircraft operations were normal through approximately 9;000 feet AGL. At that altitude; we received a PITCH TRIM MAIN INOP EICAS message; which produced a startle effect. At that time; there were no abnormal control forces and aircraft handling remained normal.I transferred control to my First Officer and confirmed that we were referencing the correct QRH: PITCH TRIM MAIN INOP. I began running the QRH when the autopilot disengaged. Following the autopilot disconnect; my First Officer pressed the quick disconnect button.Due to the ongoing mechanical issue; the aircraft momentarily flew slightly above the command bars; and airspeed decayed marginally. I immediately took control and confirmed with my First Officer that the QRH steps had been completed. At this point; control forces became heavy; requiring increased manual input to maintain desired pitch and altitude. At no time did the aircraft enter an undesired aircraft state; nor were there any altitude deviations.I stabilized the aircraft; pressed the quick disconnect button again; which froze the trim in position; and continued to hand fly. During this time; PITCH TRIM BACKUP INOP and AUTO TRIM FAIL messages appeared intermittently and later extinguished. The backup trim remained inoperative even after QRH completion.I continued to hand-fly the aircraft while my First Officer managed the Flight Guidance Panel and both FMS units as directed. After completing the applicable QRH; we requested priority handling and requested to return to ZZZ.I informed the Flight Attendant; Dispatcher; and passengers that we were returning to ZZZ for a normal landing and advised them not to be alarmed by priority handling vehicles. Both FMS units were reprogrammed; and we briefed approaches for Runways XX and XY. Performance calculations were completed for Flaps 45 and Flaps 22; and the descent checklist was completed.Due to aircraft weight; we requested delay vectors to burn fuel and remain below maximum landing weight. All maneuvering was conducted smoothly and conservatively. Once below maximum landing weight; we requested a long final for Runway XY; as the active runway had changed.I briefed my First Officer that if control forces became excessive; I may request assistance in holding control pressures. However; I was able to maintain the required control inputs without assistance.During gear extension and Flaps 45 selection; control forces increased further; however; the approach remained stable; and the landing was normal. We exited the runway and taxied to Gate XX without issue.At the gate; I completed the maintenance write-up; and passengers deplaned. Maintenance subsequently grounded the aircraft and determined that a trim system computer malfunction required replacement.There was no trim runaway; no altitude deviation; and no undesired aircraft state at any time. Safety of flight was never compromised; and the crew operated in accordance with company SOPs; CRM principles; and checklist discipline throughout the event.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.