[Cross posting list trimmed]

Musky wrote:

Rollers, folders.... all asking for trouble. Why not a garage-door
style door, single piece and folding upward with help from low-tech
springs? That's what we recommend for county hangars. Very low
maintenance, can be automated, and don't flop around in the wind.

We have a large one of those on the hanger we're in at the moment, on
the order of 50 x 25. No springs; a series of cables runs from the top
of the door to a large counterweight; attached to the bottom of the
counterweight is a cable to a _small_ winch (of the sort usually used to
move small boats onto trailers) that is used to raise and lower the door.

It works great; I just don't want to be around if the thing ever decides
to let loose. From the looks of the counterweight the thing isn't
precisely "light".