[airhead969]

Yeap. The electric trim systems tend to be automatic with speed and altitude to approximate what the pilot wants via trim up/down controls. Without trim, planes would be pitching and diving all over the place, or at least require yoke/sidestick back-pressure to hold steady. Some planes can be trimmed through enormous deflections of the horizontal stabilizer. If configured incorrectly and under the wrong conditions, incorrect trim can lead to dangerous flight characteristics like pitching up or down beyond what the elevators can handle at full deflection. A broken jackscrew (part that moves the horizontal stabilizer for the trim commands) can cause this type of dangerous configuration or even worse.