Bratukhin B-5

Bratukhin B-5
	Bratukhin B-5 conducting a test flight
Role	Transport helicopter
National origin	Soviet Union
Manufacturer	Bratukhin
First flight	1947
Number built	1 (B-5); 1 (B-9); 1 (B-10)
Variants	Bratukhin B-11

The Bratukhin B-5 was a prototype Soviet transverse rotor helicopter designed by the Bratukhin aircraft design bureau.^[1]

Development

The B-5 was an improved and larger design based on the bureau's earlier G-4, a twin-rotor helicopter, with each rotor driven by an Ivchenko AI-26 radial engine.^[1] Each engine was housed in a pod on an outrigger with the related rotor above.^[1] The programme was delayed waiting for appropriate engines and the B-5 was not completed until 1947, it only made a few short hops before the programme was abandoned due to vibration and structural flexing.^[1]^[2]

An air ambulance variant, the Bratukhin B-9 was built but was abandoned without being flown.^[2]^[3] Another variant was the Bratukhin B-10 which had uprated 575 hp (429 kW) engines and was modified for use in the artillery observation role with the military designation VNP (Vosdushnii Nabludatelnii Punk - Aerial Observation Point).^[2] The B-10 had three-seat for the crew, the cabin could hold three passengers or equipment. The B-10 flew in 1947 but although it did not have the wing stiffness problems of the B-54, demonstrating adequate handling like the B-5 and B-9 was also abandoned.^[2]^[3] A variant with an improved performance was built as the Bratukhin B-11.^[2]

Variants

B-5: Prototype, one built.
B-9: Prototype air ambulance variant, one built.
B-10: Prototype observation and reconnaissance variant, one built.

Specifications (B-10)

Data from ^[4]

General characteristics

Crew: 3
Capacity: 3 or additional equipment
Empty weight: 3,019 kg (6,656 lb)
Max takeoff weight: 3,900 kg (8,598 lb)
Powerplant: 2 × Ivchenko AI-26GVF) radial piston engine, 429 kW (575 hp) each
Main rotor diameter: 2 × 10.00 m (32 ft 10 in)

Performance

Maximum speed: 218 km/h (135 mph, 118 kn)
Range: 440 km (270 mi, 240 nmi)

References

Notes

^ ^a ^b ^c ^d Orbis 1985, p. 839
^ ^a ^b ^c ^d ^e Nemecek 1986, pp. 385-386
^ ^a ^b Gunston 1995, p.64.
^ Nemecek 1986, pp. 438-439

Bibliography

Gunston, Bill (1995). The Osprey Encyclopedia of Russian Aircraft from 1875 - 1995. London: Osprey Aerospace. ISBN 1-85532-405-9.
Nemecek, Vaclav (1986). The History of Soviet Aircraft from 1918. London: Willow Books. ISBN 0-00-218033-2.
The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985). Orbis Publishing.

[orbis-1] Orbis 1985, p. 839

[nemecek-2] Nemecek 1986, pp. 385-386

[Gunston_Russian_p64-3] Gunston 1995, p.64.

[nemecek2-4] Nemecek 1986, pp. 438-439

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