Hello MIFlyer,
Thanks for the images. I actually have those already.
I found PDFs of Paul Matt's books online a while back and the mages are not too bad though the pages are a bit out of order.
The set by Paul Matt is what I started with. The problem is that although the drawing LOOKS like an Airacobra, there are things that just do not look right when examined in detail and compared to photographs. Look qt the underside for obvious discrepancies. It did give me a "reasonable" overall length for the 37 mm Airacobra though.
Note that the second diagram in the design analysis shows an overall length that is 1.4 inches shorter than the OAL in Paul Matt's drawings. That drawing is incorrect because the 30 feet 2 inches isn't really the overall length even though it looks that way in the drawing. It is the Reference length as I call it because it is from the Fuselage datum point to the tail. It is the same for all models of Airacobra even though the barrel of cannon extends different lengths past the spinner and sometime is missing entirely on some aircraft.
The set of drawings I found that seemed to match longitudinally with most of the points was from Mongrafie Lotnicze. The problem is that they don't seem to match in cross sections which is why I was thinking the result didn't really look right.
Thanks.
- Ivan.
P.S. Attached is an image of the station diagram from a few posts back superimposed on a wireframe of my 3D model.
Interestingly, there are actually few differences in the nose except by the spinner and most of the issues are in the tail section.
Note that the station diagram happens to be missing the brace above the pilot's head and also the carb intake is shaped a little differently than photographs tend to show.