737 Runaway Stabilizer: Checklist and Manual Trim Demo

During the 737 MAX crash coverage, HN commenters linked it as a clear, pilot-led demonstration of what an MCAS runaway looks like and how hard manual trim is to crank.

A Boeing 737 pilot explains the runaway stabilizer checklist, the procedure for stopping unwanted horizontal stabilizer movement such as an MCAS activation on the 737 MAX. He walks through the steps, the trim cutout switches and the jackscrew mechanism, and shows a simulator run including the manual trim wheel effort.