This week in… 1940 – Sikorsky’s Helicopter

With the battle of Britain at its most intense, The Engineer turned its attention to a form of air transport that was still at an embryonic stage — the helicopter.

The VS-300 (above ) invented and designed by Ukrainian aviation pioneer Igor Sikorsky, wasn’t the first helicopter to fly, but it was the first to boast the single-rotor configuration that is so common today (below).

The magazine, full of admiration for the design, said: ‘The new helicopter… is equipped with a single lifting rotor, because the maximum lifting and forward flight efficiency are secured thereby and because the overall dimensions are kept down to a minimum.’ The article added that ‘with the engine placed immediately below the rotor hub, the transmission system is reduced to its barest elements.’

To counteract the turning force exerted by the rotor — which would otherwise cause the fuselage to spin round, Sikorsky introduced a small auxiliary airscrew at the tail. Rotating in a plane parallel to the plane of symmetry of the aircraft, this provided lateral thrust and counteracted the torque of the main rotor. ‘When the pitch of this airscrew is varied,’ wrote The Engineer, ‘its thrust is varied. Hence rudder action is provided.’

The article added that the two additional airscrews mounted on outriggers from the tail of the fuselage could be used to give lateral and longitudinal control providing ‘control about all three axes.’

The article was written shortly after the VS-300’s maiden flight. And although it hadn’t risen to any great heights, the magazine was justifiably confident that it soon would. ‘We congratulate Mr Sikorsky on an elegant solution to the helicopter problem, and await further progress with real expectations,’ it said.