Narrative:

I was pilot flying on leg 4 on day 2 of a 3 day trip. It was visual conditions departing on time. Immediately after takeoff while re-trimming we hear 'ding' 'trim' then saw a red warning of ptrim main inoperative. I continued to maintain control of the aircraft on the RNAV departure. I noticed trim wasn't working correctly. Captain (ca) maintained radios and got out QRH to start procedure. We had to get ATC to let us level out. We ran the QRH. If it failed but auto pilot (ap) would still engage then we could continue? Ap did engage and did appear to be working. Ca then got dispatch and maintenance on [commercial radio] while I monitored flight. After explaining all we had done then looking at whether or not a reset may not be successful in destination we decided to turn back. Once we started to return the aircraft began an uncommanded climb from 2900. I then disconnected ap and used backup trim to get aircraft back in control. Ap was used again in descent. Aircraft was out of trim and additional messages; automatic trim fail and ap elev mistrim were presented. I told ca I wanted no delays and wanted to [advise ATC]. So we did and proceeded directly to the airport for the visual to runway 26L. Landed uneventfully.threats; long duty day after min rest; previous day had maintenance issue and gate return.immediately land and deal with indications on the ground. Do not continue flight with a master warning.

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Original NASA ASRS Text

Title: EMB-145 First Officer reported a failure of the aircraft's pitch trim system during climbout. All appropriate abnormal checklists were accomplished and the crew returned to the departure airport; where an uneventful landing was accomplished.

Narrative: I was pilot flying on leg 4 on day 2 of a 3 day trip. It was visual conditions departing on time. Immediately after takeoff while re-trimming we hear 'ding' 'trim' then saw a red warning of PTRIM MAIN INOP. I continued to maintain control of the aircraft on the RNAV departure. I noticed trim wasn't working correctly. Captain (CA) maintained radios and got out QRH to start procedure. We had to get ATC to let us level out. We ran the QRH. If it failed but Auto Pilot (AP) would still engage then we could continue? AP did engage and did appear to be working. CA then got dispatch and maintenance on [commercial radio] while I monitored flight. After explaining all we had done then looking at whether or not a reset may not be successful in destination we decided to turn back. Once we started to return the aircraft began an uncommanded climb from 2900. I then disconnected AP and used backup trim to get aircraft back in control. AP was used again in descent. Aircraft was out of trim and additional messages; AUTO TRIM FAIL and AP ELEV MISTRIM were presented. I told CA I wanted no delays and wanted to [advise ATC]. So we did and proceeded directly to the airport for the visual to runway 26L. Landed uneventfully.Threats; Long duty day after min rest; previous day had maintenance issue and gate return.Immediately land and deal with indications on the ground. Do not continue flight with a master warning.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.