Were 20mm Hispanos used on P-38's Reliable?

[IceFire]

I'm not sure. I've not read much about the Hispanos in the P-38. The biggest problem with the cannon was that the initial French design was meant to be hub mounted in the nose of the aircraft carrying the cannon.

As this was impractical for the Merlin and Sabre engines the British never installed the cannon in the way it was meant to be used. Mounting cannons on the wings means that the mechanism is subject to more extreme forces and the flexing and bending of the wing. The early problems were attributable to that and to dirt and dust getting into the mechanism. There may be more issues than that... but that's the simple breakdown.

So the British and the Americans worked to fix those problems on the basic design independently.

My guess is that the P-38 and P-39 installation in the nose of the aircraft countered the difficulties with installing in the wings. Installing it in wing mounted installations for the Hispano only happened in the F4U-1C.