Gaspar,

I think that the solution you have proposed is the best one. I agree that there is no single answer, only compromises. The main risk (other than cycling the "closed when gear down" doors as you mention, which is not really a risk) is that if the airplane is in some sort of transportation cradle that blocks door movement, there could be an issue trying to open those doors and perhaps damaging the doors or linkage on power-up.

Over the years I have done two F-15s, which is one of the planes that has some doors that remain open, and some that re-close on gear down. But on powering up the airplane with gear up, while sitting in its transportation cradle, it's not unreasonable to expect the pilot will position the plane to allow free movement of the gear and doors.

One other thought .. a lot of jets are using an air actuated canopy, with an up and down motion cylinder, and one or more lock cylinders to be used with the canopy down. It would be great if you could use this same sequencer to do the canopy operations ... plus you get to sell two of them :-)

For canopy control, you don't want failsafe to put the canopy up (!), so I presume canopy down would be set up as "gear down" .. on a loss of air pressure in flight the last thing you would want is the canopy open! The lock cylinders would be set up as doors, I suppose they would have to be set so that locked = door closed. If I follow the logic here, the locks would then re-engage when the canopy goes up. This is probably ok, but not ideal .. you really only want the locks engaged when the canopy is down .. with a suitable delay for the canopy to come down, and to release before the canopy goes up. If your programming is flexible enough to customize for this application that would be great.

Dave McQueeney