Thomas-Morse XP-13 Viper

Thomas-Morse Aircraft · United States · first flew 1929 · fighter

The Thomas-Morse XP-13 Viper was an experimental single-seat pursuit biplane developed for the United States Army Air Corps in the late 1920s, powered by a liquid-cooled Curtiss Conqueror engine. Only one prototype was built.

Recognition (WEFT)

W — WingsMid-mounted, tapered
E — Engines1 × piston, nose-mounted
F — Fuselage7.16 m fuselage
T — TailConventional

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A compact biplane with a liquid-cooled engine giving a narrow frontal profile, short fuselage, and tapered wings; the inline engine distinguishes it from radial-engined contemporaries.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

Designed as one of several competing pursuit types evaluated by the USAAC in the late 1920s, the XP-13 was submitted by Thomas-Morse Aircraft — a company better known for its World War I trainers. The Viper did not outperform competing designs and no production order followed.

Variants

Single prototype only.

Where you'll see it

Never entered service.

Related aircraft

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