In
1934, North American proposed a new basic trainer to replace the
Seversky BT-8 that was tricky to fly and expensive to maintain.
The NA-16 first flew in 1935 and was purchased by the U.S.
Army Air Corps as the BT-9.
North American improved the design in 1937 by
replacing the BT-9's fabric-covered aft fuselage with metal and
installing a more powerful engine. The resulting aircraft was
designated the BT-14.
Over 100 BT-14s built for France were diverted to
Canada after the fall of France in 1940 and designated Yale.
The next series of improvements (including
retractable landing gear) to the BT-14 resulted in the AT-6
Texan.
