> That can in front of the Nieuport - is that oil or is it for a shot of fuel to get that radial started?
There's also a guy laying under it. Casualty?
*That* Nieuport still has the *rotary* engine. Except general shape, rotaries are not much like radials. The whole engine turns, the pistons hardly move, the crank is bolted to the plane. This is smoother than a rotating crank and oscillating pistons. A real issue when your engine must weigh as much as the rest of the plane.
So how do you get fuel to a rotary engine? Preferably with some carb-control (though not essential, these things flew wide-open or hardly at all.) You feed fuel-air through the crank! OK, crankcase full of explosive mixture, how do you oil? I suppose you know that one. How do you reduce crankcase explosions? What the middle series did was flow a very rich mix (too rich to burn) at the crank, pop it into the cylinders through the pistons, then used an intake/exhaust valve in the head. It let the smoke out, stayed open, air diluted the very rich mix to the right mix.
However _that_ Fokker Dr 1 Triplane seems to have a radial retro-fit. Those look like exhaust pipes blowing under the wing. A rotary has no need for exhaust manifolds, because the tailpipes would spin with the engine, blow out all over, just like you had no pipe at all. The excessive cowling on the Fokker and Nieuport was originally to direct the all-ways smog down away from the pilot's nose and gut.
Yes, Fokker and Nieuport used the same engines. Gnome rotaries made more power/weight than anything else, they sold as many as they could make pre-war, and everybody took a license to make more themselves. The big German companies liked their own engines, but Fokker couldn't get those, used Gnomes of various origins.
Got to admire the Big German Sixes. More power than the Gnome in MUCH more weight. Un-fussy, reliable. Good truck engines. Perhaps more reliability than you want when people are trying to shoot you down. 1,000-hour engines lasted just a couple hours over the front. Yes, many were dug out of the mud and sent up in a new plane, but still.