Stretching WW2 Designs

Peter Stickney wrote in message ...

(Wasn't the Mk VIII actually based on the Mk III, which was
to be a Merlin XX powered flavor that was abandined in favor of the Mk
V when it was decided that the 2-speed Merlins were better off being
put into Hurricanes? It's Rivet Counting, I know.)

The answer is not quite, the Mk III prototype N3297 was used for trials
on the merlin 60 series engines, but it was not a mark VIII prototype.
If anything the mark III was in fact considered a mark IX prototype,
along with R6700 (ex mark I) and AB196, AB197 both ex mark V,
but N3297 was very non standard.

The Air Ministry Certificate of design for the Spitfire Mk III, Merlin
61 conversion, N3297, and for R7600 "Spitfire Special" was
issued on 1 April 1942. This was the mark IX. It appears AB196
and AB197 were the definitive prototypes.

Technically the mark VIII was the mark VII without the pressure cabin,
and some early versions even came with the extended wingtips of
the mark VII. The mark VII prototype was AB450, originally built as
a mark V, there was no official mark VIII prototype.


Rivet count 123 and a third and counting.

Geoffrey Sinclair
Remove the nb for email.