NICO BRAAS MEMORIAL COLLECTION
No. 9452. Tupolev ANT-31
Source unknown

Tupolev ANT-31

11/30/2009. This fighter, designed by Pavel Sukhoi's brigade 32, was the first in the world combining un-braced wing, retractable landing gear, cowled engine, enclosed cockpit and powerful armament. Negative feature was retention of corrugated skin on wings and horizontal tail. It was powered by a 580 hp Bristol Mercury VIS2 nine-cylinder air-cooled radial engine, and was first flown on fixed skis by K.A. Popov, May 27, 1933.

The improved second aircraft, designated ANT-31bis, I-14bis, was fitted with the 712 hp Wright Cyclone SGR-1820-F2 nine-cylinder air-cooled radial engine. It had a new wing and horizontal tail with smooth skin, narrow-track landing gear retracting outwards, and a narrow open cockpit.

The aircraft first flew (also on skis) in March 1934 and testing was favorable and measured figures were outstanding, but there were problems with spinning, and with the narrow track landing gear and its manual operated retraction mechanism. Despite this an order for 55 aircraft was placed.

Armament in the production aircraft consisted of two 0.787 in (20 mm) cannons and two 0.3 in (7.62 mm) machine guns. The engine was a 730 hp Soviet version of the Cyclone, the M-25A. However, the similar powered Polikarpov I-16 proved superior, and with the earlier stated problems still unsolved, production of the ANT-31bis was cancelled after 22 aircraft produced, the remaining airframes already under construction were scrapped.

Created November 30, 2009