Engineering:Sikorsky S-20

RBVZ S-XX
Role	Fighter
Manufacturer	RBVZ (Russo-Baltic Wagon Works)
Designer	Igor Sikorsky
First flight	1916
Introduction	1916
Retired	1920
Primary user	Imperial Russian Air Service
Number built	5

The Sikorsky S-20 (named after its designer) or RBVZ S-XX (named after its manufacturer) was a Russian single-bay unequal span two-seat biplane designed by Igor Sikorsky in 1916. Displaying some Nieuport influence, it saw very little service during World War I.

Five S-XX aircraft were built in September 1916, with the first two powered by the 100 hp Gnome rotary engine which had powered its predecessor, the RBVZ S-XVI. However, the other three were powered with the 120 hp Le Rhone engine, with which they were allegedly faster than the French Nieuport 17.

Operational history

The S-XX saw little service because it was viewed as inferior to newer enemy aircraft, and no series production was undertaken. As such, only five aircraft were ever produced.

List of operators

Russian Empire

• Imperial Russian Air Service

Specifications

General characteristics

• Length: 6.5 m (21 ft 4 in)
• Wingspan: 8.6 m (28 ft 3 in)
• Height: 2.6 m (8 ft 6 in)
• Wing area: 17 m² (180 sq ft)
• Empty weight: 395 kg (871 lb)
• Gross weight: 570 kg (1,257 lb)
• Powerplant: 1 × Le Rhône Type 9Jb 9-cylinder air-cooled rotary piston engine, 89 kW (120 hp)
• Propellers: 2-bladed fixed-pitch propeller

Performance

• Maximum speed: 180 km/h (110 mph, 97 kn)
• Range: 390 km (240 mi, 210 nmi)
• Service ceiling: 5,600 m (18,400 ft)
• Time to altitude: 2,000 m (6,600 ft) in 6 minutes 20 seconds
• Wing loading: 33.0 kg/m² (6.8 lb/sq ft)
• Power/mass: 0.21 hp/kg

Armament

• Guns: 1 x 7.7 mm Lavrov machine gun

References

Bibliography

• William Green and Gordon Swanborough. The Complete Book of Fighters. Colour Library Direct, Godalming, UK: 1994. ISBN:1-85833-777-1.