On 24 November 1961, a machine that looked like somebody had bolted two helicopters to the wingtips of a transport aircraft lifted 16.4 tonnes to two and a half kilometres, set six world records in one flight, and landed thirty minutes later with its fuel warning lights on.

Six weeks earlier the same design had flown at 356 km/h, faster than any convertiplane in the world.

Four of them were built. Two crashed, killing nine people. Not one survives.

The idea: get rid of the tug

The concept came from a Kamov engineer, Vladimir Barshevsky, who in 1951 was working on the problem of helicopter range. The method then in use was to tow a helicopter behind a Li-2 with its rotor autorotating. Barshevsky’s thought was obvious once stated: give the helicopter its own wings and its own propellers, and you can throw the tug away.

Kamov’s deputy took the proposal to the Kremlin. A ministerial telephone call came the same night, and by June 1954 a government decree ordered three aircraft built.

What made it work in theory was high rotor speed. At cruise the wing carried up to ninety percent of the lift, so the rotors could run in a near-autorotative, low-drag state with their blade tips going supersonic — enough disc loading to stay damped, not enough to cost much drag. Rotor blade loading was 45 kg per square metre against 18 on Kamov’s little Ka-15.

What the Soviet military actually wanted

Not a research aircraft. The requirement was to move a ballistic missile and its launcher at speed into terrain with no runways, and it was handed to Mil and Kamov simultaneously. Mil built the Mi-6, a very large conventional helicopter. Kamov built the Ka-22.

The 1956 specification asked for five tonnes over roughly 700 kilometres or four tonnes over 1,500, at not less than 400 km/h. The cargo hold, 17.9 metres long and 2.8 metres high, was comparable in volume to an Antonov An-12, and the entire nose swung open to starboard so a vehicle could be driven in.

The competition was, in effect, a race between two answers to the same question. The helicopter won it.

Learning to fly it

The first lift-off from the ground came on 17 June 1959; the first free hover on 15 August, when Dmitry Yefremov got it two or three metres up three times, the longest hover lasting a minute. By 18 September the test diary records eleven minutes airborne and fifteen landings.

It was not a pleasant machine at low speed. Yuri Garnayev, one of the LII test pilots brought in, wrote after his second flight:

Above about 40 km/h it transformed — the test diary records that it became stable, moved into a normal helicopter régime, the vibration dropped and there appeared, in the engineers’ phrase, a pleasant state of normal flight. Lead engineer Dordan recorded what the blade tips sounded like at high speed: the compression waves, he said, were like a heavy machine gun.

The Ka-22 demonstrating at Tushino in 1961 — the only time Western observers ever saw it fly.

The records

On 7 October 1961, fitted with spats over the wheels and a fairing behind the cockpit, the Ka-22 was flown over a measured base at 356.3 km/h, tracked by four cine-theodolites at a flight weight of about 29 tonnes. That beat the Fairey Rotodyne’s convertiplane mark.

The payload attempt on 24 November was the bigger one. Build-up flights had taken it to 44.1 tonnes. On the record flight it took off at 44,670 kg and lifted 16,485 kg to 2,557 metres, taking six records in a single half-hour sortie. The lead engineer’s log entry is a model of understatement: the machine behaved normally, programme number 8-9 complete.

The flight engineer, Yevgeny Filatov, interviewed fifty years later, was less restrained about the rivalry with Britain.

Asked whether the crew had calculated the risk before the speed attempt, his answer was blunter: what was there to calculate? It was like a game of Russian roulette.

The full story of the Ka-22 and the later Ka-35 project.

Dzhusaly, 28 August 1962

Two Ka-22s left Tashkent for Moscow on 28 August 1962, being ferried for acceptance testing. Aircraft 01-01 entered the Dzhusaly control zone in Kazakhstan at 11:13 asking for a straight-in landing in aeroplane mode. At 11:20 it rolled left, went inverted, and hit the ground two kilometres short of the runway.

The commission found that a turnbuckle on the cable controlling the collective pitch of the right rotor had come undone in flight — testing showed that unlocked turnbuckles unwound under vibration. Inspections afterwards found the same assembly error on two of the three remaining airframes.

All seven aboard were killed, among them Dmitry Yefremov, the pilot who had first got the machine off the ground. Filatov survived only because he had been moved to another crew shortly before.

Tashkent, August 1964

The last flight was stranger. Aircraft 01-03, heavily instrumented and fitted with an autopilot, was fifteen minutes into an acceptance sortie at 310 km/h when it suddenly turned right — a turn that full rudder and aileron could not arrest. It went round nearly 180 degrees.

Garnayev, in the right seat, believed the tractor propellers were at fault and unloaded them by sharply increasing rotor collective. The turn slowed but the aircraft pitched into a steep dive. The flight engineer jettisoned the flight-deck hatches; one struck the starboard rotor and broke a blade, and the resulting imbalance tore the entire starboard engine nacelle off the wing. Garnayev ordered everyone out.

Colonel S. G. Brovtsev, who was flying, and technician Rogov were killed. Three men got out. The commission never established what had started it.

Archive footage of the Ka-22 in the air.

Why it lost

Partly the crashes. Partly the handling — Russian accounts describe an aircraft that was extremely hard to fly and resembled neither a helicopter nor an aeroplane. Partly the mechanics: enormous power losses through the gearboxes and drives, and each rotor blowing its downwash straight onto the wing beneath it.

And partly the engines. When the intended 5,900 hp Kuznetsov units were replaced by 5,500 hp Solovievs, the OKB reckoned the 800 horsepower cost them roughly half their useful lifting capacity.

But mostly it lost because the Mi-6 had already won. Mil’s helicopter entered production at the end of 1959 and service in 1963. The bureau memoir puts it plainly: the competition ended in victory for the helicopter.

Two Ka-22s stood on the factory airfield at Tashkent for years afterwards. The last one, reportedly ninety percent complete, was destroyed in the late 1990s after several museums declined to take it.

There is one more thing worth noting. Gordon and Gunston, cataloguing the Ka-22’s failings — the complexity, the transmission losses, the difficulty of transition — added a single dry sentence: similar charges could be levelled against today’s V-22 Osprey.

Sources: Yefim Gordon and Bill Gunston, Soviet X-Planes (Midland, 2000); airwar.ru (Kamov OKB participant memoir); Viktor Myasnikov, “Ка-22 показал, кто всех быстрее и сильнее”, Nezavisimoye Voyennoye Obozreniye, 3 February 2012; GlobalSecurity.org; Vertical Flight Society Vertipedia; English and Russian Wikipedia; Wikimedia Commons.