Wright R-975-E3 Whirlwind (420 hp (310 kW)) USAAC (trials) Ex-NA-16, won against Seversky BT-8 and Curtiss-Wright CW-19R, to Argentina in 1937



Variants could have an open cockpit (the prototype and the NA-22) or be under a glass greenhouse that covered both cockpits. On some variants, the rear of the canopy could be opened for a gunner to fire to the rear. A variety of air-cooled radial engines, including the Wright Whirlwind, Pratt & Whitney Wasp and Pratt & Whitney Wasp Junior of varying horsepowers, could be installed depending on customer preferences. The fuselage was built up from steel tubes and normally fabric covered; however, later versions were provided with aluminium monocoque structures.HARVARD NA-26

Basic Combat demonstrator (NA-26)

NA 26One-armed demonstrator and the first variant with a retractable undercarriage, eventually sold to RCAF who modified it with Yale and Harvard parts.
powered by Pratt & Whitney R-1340 Wasp

In 1937, the North American NA-26 prototype won a competition for a basic combat trainer for the USAAC, and, in due course, it went into production as the BC-1. Little could North American Aviation know how famous and numerous its new trainer would become, with demand for it spurred on by the urgent needs of WW2. The aircraft was produced in several versions and it flew with many arms, with production continuing long after WW2. The metal-framed BC-1 had a metal skin on wings and tail unit, fabric-covered control surfaces and mainly fabric-covered fuselage. There was a Pratt and Whitney R-1340 9 cylinder Wasp radial up front, and an inwardly retracting undercarriage.


Dutch NA-27 (NA-16-2H) demonstrator in Air Force colours. It was lost at De Vlijt when destroyed by Bf.110s on 11 May 1940.


NA-31 (NA-16-4M) in Sweden. Virtually the same as the BT-9C, the only differences were the Wright R-975-E3 engine and Goodyear tyres. The NA-31 was scrapped in November 1949 after some 1881 hours of flying. The Swedish AF designation was Sk 14.


The NA-44 was a one-off prototype that was the first with a metal-skinned rear fuselage. Powered by a 750hp Wright R-1820 (!), she featured the earlier-style outer wings as seen on the BT-9, NA-57/NA-64 & Harvard Mk I, and also featured a ‘wet wing’ fuel tank for the centre section. She went to South American for a sales tour, targeting countries there that were looking for a cheap attack aircraft. The sales tour led to orders from Brazil and Chile, although those examples were R-1340 powered. In 1940, the NA-44 (as well as the NA-26 – the prototype retractable gear NA-16 variant) was acquired by the RCAF and given the RCAF serial number 3344. She served the war at RCAF Station Trenton, and was known to engage in dogfights with Hurricanes on occasion (and won!), hence the blue/red paint job. After the war, she was slated to be sold off, however, she disappeared before the buyer could collect her at Trenton. Shane Clayton.



NA -64