Keystone NK

The Keystone NK or Keystone Pup was a two-seat biplane trainer built by Keystone Aircraft for the United States Navy.

Design and development
The NK was an open-cockpit two-seat biplane with a convertible wheel or float landing gear. It was powered by a 220 hp (164 kW) Wright R-790 Whirlwind. The company prototype designated the Pup was entered into a United States Navy design competition for a trainer and was awarded a contract for three prototypes designated XNK-1. Following evaluation a production batch of 16 was ordered designated NK-1 which were delivered during 1930.

Variants

 * Pup
 * Keystone prototype, one built.


 * XNK-1
 * Prototypes for Naval variant of Pup, three built.


 * NK-1
 * Production aircraft with minor changes, 16 built.

Operators

 * United States Navy
 * United States Navy