While we are up in the clouds here's an image which contains a small panel, image 1, red box, and I don't need to inform everyone who has ever sat in a piston engined airplane what the shape of the surrounding area looks like in the black box. Some planes have two, others four. The object in the yellow box looks as though it was once covering the panel, it has what appears to be a handle and locking device. Image 2 is the panel, yellow box and the obvious shape that all piston engined flyers would recognise but, look at the shape in the red circle, where you would expect to see it isn't it? Image 3 is the same panel from a different angle.
Last image is the whole panorama.