Grigorovich DI-3

Grigorovich DI-3 (Russian: Григорович ДИ-3), (Dvukhmyestnyi Istrebitel - two-seat fighter), was a prototype two-seat fighter developed in the Soviet Union in the 1930s. It was intended to be a long-range escort fighter developed from the DI-2 with improved range and performance comparable to single-seat fighter aircraft of the time. DI-3 was a single-bay biplane of mixed construction with a twin-rudder tailplane of variable incidence. Although initial tests demonstrated flight characteristics comparable to Polikarpov I-5, the addition of armament and operational equipment caused significant degradation in performance and DI-3 did not enter mass production. The prototype was subsequently fitted with an enclosed cockpit and used as a VIP transport.^[1]

Specifications (DI-3)

Data from Shavrov 1985^[1]

General characteristics

• Crew: Two
• Length: 7.8 m (25 ft 7 in)
• Wingspan: 11.8 m (38 ft 9 in)
• Height: ()
• Wing area: 30.1 m² (324 ft²)
• Empty weight: 1,487 kg (3,278 lb)
• Loaded weight: 2,122 kg (4,678 lb)
• Powerplant: 1 × BMW VIz7,3 V12 engine, 545 kW (730 hp)

Performance

• Maximum speed: 256 km/h (138 knots, 159 mph)
• Service ceiling: 6,300 m (20,669 ft)
• Wing loading: 70 kg/m² (14 lb/ft²)
• Power/mass: 257 W/kg (0.16 hp/lb)
• Time to altitude: 17.5 min to 5,000 m (16,400 ft)
• Horizontal turn time: 13 sec

Armament

• 2× 7.62 mm (0.3 in) synchronized PV-1 machine guns
• 1× 7.62 mm (0.3 in) DA machine guns on a manually operated gun mounting.

References