12/31/2023. Remarks by
Johan Visschedijk: "Powered by a 220 hp Wright J-5 (R-790 Whirlwind) engine and named Pup, Keystone Aircraft created this open-cockpit two-seat biplane in 1928.
Keystone Pup (
Johan Visschedijk Collection)
The Keystone Pup could be flown with a wheels or float landing gear.
The Pup was entered into a USN design competition for a trainer, it performed well, and Keystone received an order for three prototypes based on it. These where designated XNK-1 and allotted the BuNos. A-7941 to A-7943. Subsequently the markings U.S. Navy and XNK-1 were applied to the Pup.
Keystone NK-1 (A-8053) (
Johan Visschedijk Collection)
After successful testing of the prototypes, an order was issued for sixteen production aircraft, designated NK-1, BuNos. A-8053 to A-8068, these were delivered in 1930."