Spad XII Ca1
During WWI, several specially equipped SPAD XII Fighter planes were built with 37 MM cannons that fired through the propeller shaft. The design had several faults including noxious gas that filled the cockpit after firing the cannon. Another problem was that the cannon was a single shot and had to be reloaded by hand after each shot! Couple that with the violent energy of the recoil, the stress of aerial combat and the speed of the plane, this was no easy task. Still, if you hit your target, it was destroyed. SPAD "0" was the only Ca.1 in the American Air Service, it was originally intended for the American Ace David Putnam, but when Putnam was KIA over the front, the machine was given to his friend Capt Charles J. Biddle, CO of the 13th Aero Squadron, The Devil's Own Grim Reapers. Capt Biddle found the SPAD XII Ca.1 37 mm cannon difficult to operate, but stated that "if a shot ever hits a Hun, he might as well say his prayers...".
Capt. Biddle had 7 confirmed victories (10 probable) in WWI flying first with the Escadrille N. 73, then with Lafayette Escadrille and later with the 103rd Aero Squadron U.S.A.S. and the 13th Aero Squadron U.S.A.S. where he was CO, he eventually ended the war as CO of the 4th
Pursuit Group. Capt. Biddle's SPAD XIII was also numbered "0".
Don Henderson
