Tupolev I-4
Role	Fighter Type of aircraft
National origin	Soviet Union
Manufacturer	Tupolev
Designer	Pavel Sukhoi
First flight	1927
Retired	1933
Primary user	Soviet Air Force
Number built	369

The Tupolev I-4 was a Soviet sesquiplane single-seat fighter. It was conceived in 1927 by Pavel Sukhoi as his first aircraft design for the Tupolev design bureau, and was the first Soviet all-metal fighter.

Design and development

After the first prototype (under the development name Andrei Nikolayevich Tupolev fighter 5 | ANT-5), the I-4 was redesigned with a new engine cowling to decrease drag, with added rocket launchers on the upper wing and a larger tailfin. The lower wing was predominantly an attachment for the wing struts; it was almost removed in the second series, the I-4Z (where the lower wings were greatly shortened), and totally removed from the I-4bis, thus transforming the aircraft from a sesquiplane into a parasol-wing monoplane.

Operational history

The I-4 was used as a parasite fighter in experiments with the Tupolev TB-1 bomber. The aircraft was in Soviet service from 1928–1933. A total of 369 were built.^[1]

Variants

• ANT-5 : Prototype.
• I-4 : Single-seat fighter aircraft.
• I-4Z : Single-seat fighter with span of lower wings greatly reduced.
• I-4bis : Monoplane version (lower wings totally removed).
• I-4P : Floatplane version.

Operators

 Soviet Union

• Soviet Air Force

Specifications (I-4)

Data from ^{[citation needed]}

General characteristics

• Crew: 1
• Length: 7.27 m (23 ft 10 in)
• Wingspan: 11.42 m (37 ft 6 in)
• Height: 2.82 m (9 ft 3 in)
• Wing area: 23.8 m² (256 sq ft)
• Empty weight: 978 kg (2,156 lb)
• Gross weight: 1,430 kg (3,153 lb)
• Powerplant: 1 × Shvetsov M-22 9-cylinder air-cooled radial piston engine, 343 kW (460 hp) (Bristol Jupiter)
• Propellers: 2-bladed fixed-pitch propeller

Performance

• Maximum speed: 257 km/h (160 mph, 139 kn)
• Range: 524 km (326 mi, 283 nmi)
• Service ceiling: 7,655 m (25,115 ft)
• Wing loading: 60 kg/m² (12 lb/sq ft)
• Power/mass: 0.25 kW/kg (0.15 hp/lb)

Armament

• Guns: 2 × 7.62 mm machine guns