Originally Posted by
HalinTexas
I would have recognized a runaway trim. Held the electric trim back until I didn't need so much control force. At the same time I'd call for the "Runaway Stab Trim" QRC/QRH. Used to be a memory item.
Both accidents used the trim to stop the motion, but NOT to reverse the trim. Anyone that hand flies the airplane much knows that you have to trim the hell out of Boeings, and trim some more. I suspect some serious training deficiencies, along with lack of experience.
I'm not buying that they could trim manually. They were doing less than 350KIAS. I suspect they didn't pull the handle out to crank it.
The stab in an extreme nose down position with the elevator in a nose up position at 350KIAS would put a significant force on the stab toward the nose down position. Perhaps if the stab and elevator were closer to a trimmed condition trimming at 350 might not be a problem. High speed high deflection - different story.