The four Yak-36 prototypes explain the distinct Soviet route to V/STOL flight. During early tethered tests, strong suction drew hot exhaust back into the aircraft and increased the power needed to hover. The first tethered flight came in January 1963, an untethered flight followed in June, and a successful transition followed on 16 September. Soviet designers were pursuing a larger, faster aircraft than the British P.1127, Kestrel, and Harrier line. Similar engineering problems produced convergent solutions, while the roughly two-ton rise in empty weight from Yak-36 to Yak-38 shows how much Soviet design ambitions grew.
Chapter · 2:20-7:26
Yak-36 lessons behind Soviet V/STOL development
The Yak-36 trials show how larger aircraft and higher speed ambitions shaped the Soviet route to V/STOL flight.