MD-80 Series (DC-9-80) Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 20000
Aircraft Equipment Problem Critical; Inflight Event / Encounter Loss Of Aircraft Control
Flight Crew Executed Go Around / Missed Approach; Flight Crew Overcame Equipment Problem
Aircraft
On approach at 2500 feet autopilot off configuring to flaps 40; the stabilizer trim failed to move using the Captain's control wheel trim switches. The stabilizer also failed to move using the long suitcase trim handles or the First Officer's control wheel trim switches. Considerable back pressure was required as the aircraft pitched nose down. A go around was performed and an [ATC was advised]. When the flaps reached the 15 degree setting stabilizer movement was regained. The QRH STAB INOP - IN FLIGHT checklist was completed. With the stabilizer trim now operating a normal ILS approach with an extended final and early configuration was planned to the 12;000 foot runway. As fuel was becoming a concern; the STAB INOP - IN FLIGHT checklist was briefed as an immediate backup if necessary. On the second approach as the flaps were transitioning to the 40 position the stabilizer trim jammed again. The STAB INOP - IN FLIGHT checklist was immediately initiated and a flaps 15 landing with the appropriate speeds was accomplished per the checklist. The flight landed without incident.The excellent and detailed training I received especially on trim problems during recurrent training made this a non-event where the successful outcome was never in question. The improved stabilizer QRH checklist flow made the incident easy to diagnose and remedy with relative ease during a stressful situation. The First Officer performed perfectly and with calm deliberation. With support from these resources it creates a safe flight environment during those times of mechanical failures that cannot be totally eliminated. My gratitude and thanks goes out to all of our instructors and check airmen that prepared me for this problem.
We did receive a GPWS warning on final due to the incorrect switch being selected. We selected 'Terrain System' override instead of the 'GND PROX WARN OVRD.' I think this occurred due that in all previous human factors GPWS flight examples the ground proximity override switch is on the lower display panel on those aircraft and that's where my mind immediately went; most likely due to simple task saturation at that moment. However; on the main stabilizer issue we had; the immense amount of training from the flight training department on stabilizer issues on the MD80 really helped in this situation. Given the strong pitching motion of the aircraft; the flight training department's strong emphasis on stabilizer issues is great because pilots may have their hands full flying an airplane that wants to go into an adverse pitch attitude; just like we did. In addition the Captain's strong emphasis on company and aircraft procedures greatly helped the situation as we worked together through each unusual aspect of this incident efficiently and effectively; communicating with each other and ensuring a safe outcome to the flight.
MD-83 flight crew reported experiencing a stabilizer trim failure on approach.