Some aircraft have yoke aft limit switches that disable electrical stab trim I believe. As has been stated above, stab trim runaway is common knowledge and an

Some aircraft have yoke aft limit switches that disable electrical stab trim I believe. As has been stated above, stab trim runaway is common knowledge and an emergency procedure (EP) that is trained for. Arresting the descent with yoke while activating the electrical stabilizer trim cutout and having the pilot-not-flying manually rotate the stabilizer wheel in the opposite direction or at least attempting to hold it from adding more trim if cutout is not working. Many pilots will position a knee or shin on the stabilizer wheel so they are aware when trim is being run. The yoke itself holds a trim adjustment mechanism so the pilots can adjust trim while retaining arrest authority on the yoke as well, though in the case of runaway trim the cutout would be used and manual operation of the wheel would be required. I believe another commentator mentioned the jack screw, this will very likely have survived the crash and investigators will be able to tell exactly where the nut was positioned (trim setting) when impact occurred. With stab trim runaway being such well trained for EP [assumed as its common in my circles] I would be surprised if that were the root cause unless pilot error is attributed to suspecting another fault mode. I am not familiar with commercial aviation as much, is it common place to transition from the critical phase of flight during take off to autopilot (AP) climb at such a low altitude? If they were not on some sort of AP mode I can't see how they wouldn't notice the trim being added as a serious issue. -Sorry I had meant to post this as a response above and not directly to your post