[Graham Boak]

Yes it looks good, but remember that promises in 1936 only mean deliveries in 1938, when it wouldn't look quite so good. Hagedorn quotes the NA-50 first delivered in March 1939 at 295mph at 9.500 ft, which is indeed quite good - if ever proven. The P-64 with a slightly more powerful engine, cannon and retractable undercarriage, is only credited with 270mph at 8,700ft. The NA 50 only had 2x0.303 machine guns. It was delivered only seven months after the order in August 1938, but NA had much more experience in building the aircraft, a flowing production line, and an extra two years to work up details of the design. Up to four forward firing guns was a capability of all NA 16 variants (at least theoretically if not practically) but this was rarely if ever carried.

There is however the political matter: would NA have been able to get permission from the then-isolationist US State Department to sell fighters to Finland? There was considerable fuss within the US over the sale of combat aircraft to their long-time ally France.

Looking further at the P-64, it has an empty weight of 4,660lb, a normal loaded weight of 5,990lb, and a maximum weight of 6,800lb. The cannon and retractable undercarriage would add weight, but it still makes those quoted for the NA 16-5 appear optimistic.

Looking at the D 21, it's top speed is only 9mph slower than that projected for the NA 16-5., and a service ceiling of 36,010ft. It doesn't seem that bad a deal.