If the plane is moving forwards, I would guess that's what gives it the bowl shape, in the same way the blades are curved due to the rotation. Of course, if the plane is not moving, all bets are off and I have no idea…

Actually film cameras typically either had an in lense shutter or a focal plane shutter. The in lense shutter exposes the entire negative at the same time, but the focal plane shutter, found in any single lense reflex, does not, at least at the higher speeds. This gives rise to distortions in moving subjects. The shutter consists of two moving blinds which travel across the film plane. At low speeds there is a time where the whole film plane is exposed but at high speeds the two blinds form a moving slit which travels across the film. For a typical 35mm single lense reflex, the highest speed at which the film is fully exposed is 1/60 of a second, and this speed is used for flash. At higher speeds, motion distortion effects may be seen, but they would be most obvious in vertically moving objects. Objects moving horizontally would be just stretched or shrunk a little

I've been told that the reason that artists depict things like fast moving cars with the radiator leaning forwards is that that is how they appeared in photos at the time, taken with a vertical run shutter. Most modern SLRs have a horizontal run shutter, although I have a Pentax MX with a vertical run shutter with metal blades. That also runs faster than most, with the flash sync at 1/125 second.

John