Worth repeating, when using a shoulder mounted camera, there is an issue relying on the seat belt because it is often loosened to be allow the camera operator to rotate his hips toward the door.
This helps to prevent the shoulder mounted camera from bumping against the seat back and reduces the need to twist the upper body and lean forward which is tiring.
The goal is to have the maximum scope to pan forward and aft without the airframe comming into shot.
A greater degree of body twisting is required when shooting out the right hand side to prevent camera bumping top of seat as camera is on the right shoulder.
On the other hand the lens is projecting a foot or so further towards the open door and so with less chance of airframe comming into shot (when shooting forwards) on the rhs than when shooting from Lhs.
If legal, removing seat back and/or the seat cushion can help with clearance. BTW, im told that unless the seat cushion is a very firm high tech foam it is better off without it in a serious crash.
Its interesting that sitting on the floor with legs dangling or resting on step seems to be less popular than it was a decade ago.
Mickjoebil