Residential garage door openers

[FionaZuppa]

I haven't seen one of the Wayne Dalton idrive type openers yet, but I was wondering how do they handle power failures? The traditional carriage type just have a rope to disconnect them from the door.

yes, it has a release pull on one side. with release the door still has spring. but if a spring breaks there are cam/pawl safety mechanism on each side to prevent the door from swinging down and crushing something/someone, etc.