Pete, the original aircraft was a wooden frame (mostly balsa) that was then covered in doped fabric. The proposed fighter variant (P110) would have been wrapped in aluminum, and I'm sure it would have had some other main structural elements made of it as well.
I'm almost
positive that the replica has the same sort of CR prop setup as the original. What really interested me about that particular part of the aircraft was that the engines are mounted directly inline with each other, but the shafts are not sleeved one inside the other as you would normally imagine. The engines are both canted a few degrees port or starboard so that the prop shafts enter the actual cockpit on either side of the pilot's ass. Then, through a series of universal joints the two shafts then converge in a gearbox just forward of the main panel in the cockpit. Unfortunately, the specifics of what happened once the shafts entered the gearbox is unknown since the prototype was stripped of all useful metal materials before being completely forgotten in a shed in France some time in the 60s. So the restoration and the subsequent build of the replica was done with a bit of "educated guessing", i.e. - they just went with what sounded right.
Aside from the complicated engine setup, Bugatti also incorporated some other interesting design parameters. I'm not positive, but it might have been the first aircraft to make use of the Y-tail design, something Bill Lear later decided would work well with his Lear Fan. There was also the small idea to tie the flap condition to the altimeter, giving the pilot the ability to set the altitude that the flaps would start lowering and not have to worry about taking his hands off the throttle to mess with it. I'm not sure if that last one made it into the current aircraft, since it seems like there could be some potential issues with it. The flaps were also part of the spoiler system. If you opened the spoilers, the flaps would move as well and then lower some more if you dropped in flap controls, as you can see below:
Oh, and she should move at a sultry 500 mph in level flight once they throttle her up . . .
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