Terribus,

Just a couple of points.

The 'wing-top'gun on the SE 5 was a Lewis with the 'infantry' cooling jacket removed and a 96 round magazine fitted, not a Vickers 'K' (the 'K' is a 1930s design I think).
The technique you describe of shooting into the 'blind spot'was a favourite of 'Billy' Bishop, apparently, he kept his lewis gun in the 'loading' position on the quadrant mount (pointing almost straight upward) dived under his opponent (who thought himself safe as most single seat 'planes fired forward) and stitched them from tail to engine (or t'other way).

WWII. Wasn't the P 51 'Mustang' an American design?

I'm glad someone mentioned the DH Whirlwind, I'd quite forgotten it(would I be right in thinking it was based on the DH 88 from the Britain-Australia race?).

Regards

Walrus