Uncleal, the gear-reduction Hispano was commonly used in the later part of the War, and was indeed the powerplant fitted to the SPAD XII Ca.I. This was the plane that had been armed with the thru-hub firing Hotchkiss 37mm cannon and was designed in part by Guynemer and used by him to score at least two of his victories. Fonck also used the SPAD XII, scoring 11 of his victories with the craft. It did however have a fair number of problems. It was quite nose-heavy for one thing. Also, the Hotchkiss was a single-fire weapon and reloading in flight was horrible as air pressure coming through the barrel when you opened the breech pushed the spent shell gas into the cockpit and damn near choked the pilot into unconsciousness.
It's the only only way,
It's the only trick to play;
He's the only Hun, you're the only Pup,
And he's only getting the wind right up.
So go on and do not stop
'Til his tail's damn near your prop;
If he only crashes this side in flames,
Well, only then they'll believe your claims.
So keep him tight in your Aldis sight,
It's the OOOOOOOOO-nly way!