Narrative:

Departed; at about 800 ft I noticed that I couldn't trim the aircraft nose up but nose down was working. I continued to hand fly and my first officer (first officer) ran the QRH. We called dispatch; tried on VHF with no luck and then HF. Got a patch with dispatch and [maintenance control]. [Maintenance control] said follow the QRH; as we did. I advised the lead flight attendant of our situation. [Advised ATC] as a precaution and requested to have the emergency equipment standing by. Landed runway xx; flaps 15 everything was normal; taxied to the gate.

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Original NASA ASRS Text

Title: B737 Captain reported the elevator trim only worked in the pitch down direction.

Narrative: Departed; at about 800 ft I noticed that I couldn't trim the aircraft nose up but nose down was working. I continued to hand fly and my FO (First Officer) ran the QRH. We called dispatch; tried on VHF with no luck and then HF. Got a patch with dispatch and [Maintenance Control]. [Maintenance Control] said follow the QRH; as we did. I advised the lead flight attendant of our situation. [Advised ATC] as a precaution and requested to have the emergency equipment standing by. Landed runway XX; flaps 15 everything was normal; taxied to the gate.

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.