Hey all, again brainstorming ideas, and looking to the knowledge base here for existing examples.
I'm looking for a case where a door or other movable structure (access panel, whatever) in an aluminum airplane is used to carry significant loads, basically resolving the loads as if the cutout wasn't there.
For context, my fuselage naturally has a pretty typical longeron structure for a low wing design, with no loads resolved through the canopy; details are still being worked out. However, I'd really like to put a door right where the passenger side top longeron is. Basically, for reasons that are combination of unique to my design lay out, and due to mobility constraints of certain people I fly with, I'd like the door sill under the (open) canopy to fold out of the way to allow stepping in without stepping over the sill. Would really, really like to. 50+ lbs of like to, if that's what it takes. I can see two ways of doing this. The first is to beef up the remaining three longerons, and take the loads there. Not ideally placed, not optimal, but possible with some (TBD) weight penalty. The other option I can see is to put the longeron inside the door, and use some connector that gets fastened each time the now-structural door is closed -- so not bolts, but... something?
Running this through my mind, I'd probably want a mechanical interlock so the canopy can't close until the door is latched with a structural door, to avoid takeoff with it open; and I'd probably want to handle > 1 g loads after failure of that part, just for piece of mind. Opening this door would not be required for emergency egress, so it doesn't have to be super quick/simple/single motion to open.
But... examples, context, standard approaches would greatly help here!
I'm looking for a case where a door or other movable structure (access panel, whatever) in an aluminum airplane is used to carry significant loads, basically resolving the loads as if the cutout wasn't there.
For context, my fuselage naturally has a pretty typical longeron structure for a low wing design, with no loads resolved through the canopy; details are still being worked out. However, I'd really like to put a door right where the passenger side top longeron is. Basically, for reasons that are combination of unique to my design lay out, and due to mobility constraints of certain people I fly with, I'd like the door sill under the (open) canopy to fold out of the way to allow stepping in without stepping over the sill. Would really, really like to. 50+ lbs of like to, if that's what it takes. I can see two ways of doing this. The first is to beef up the remaining three longerons, and take the loads there. Not ideally placed, not optimal, but possible with some (TBD) weight penalty. The other option I can see is to put the longeron inside the door, and use some connector that gets fastened each time the now-structural door is closed -- so not bolts, but... something?
Running this through my mind, I'd probably want a mechanical interlock so the canopy can't close until the door is latched with a structural door, to avoid takeoff with it open; and I'd probably want to handle > 1 g loads after failure of that part, just for piece of mind. Opening this door would not be required for emergency egress, so it doesn't have to be super quick/simple/single motion to open.
But... examples, context, standard approaches would greatly help here!
