Where its contemporaries were fabric-and-wire biplanes, the I-16 was a low-wing cantilever monoplane with a retractable undercarriage — a combination widely credited as the first to reach front-line fighter service anywhere in the world. The stubby fuselage was a wooden monocoque skinned in birch plywood, mated to a fat air-cooled radial chosen partly for its tolerance of battle damage. Some pilots disliked the sliding canopy so much that later batches reverted to an open cockpit. Radical and cramped, it pointed straight at the fighters of the Second World War.

The I-16’s virtues and vices came from the same source: a very short fuselage. It made the fighter light on the controls and vicious in a horizontal turn, but also unstable in pitch — it “reacts to the slightest deviation of the controls,” as one account put it, and could snap into a spin. High approach speeds and an oil-fouled windscreen made landings a handful, and the manually cranked gear (about 44 turns) often left novices porpoising as they wound the wheels up. The maxim followed naturally: master the Ishak and you could fly anything.

Over the Mongolian steppe in August 1939, a flight of I-16s under Captain N. Zvonarev carried something new beneath their wings: RS-82 rockets. Salvoed into Japanese formations, they are credited with the first aircraft ever downed by air-to-air rockets — Soviet claims range from around 13 to 19 machines, and should be read as claims. It was a preview of a weapon that would define the jet age, fired from a propeller fighter.

The I-16 was a Soviet state product of the 1930s, built by the thousand in a command economy and never sold on an open market, so no dependable flyaway unit price or cost-per-flight-hour figure survives in the public record. What is documented is scale, not money: production is commonly estimated at around 10,000 airframes (counts range roughly 8,600 to 10,300 depending on how two-seat trainers are tallied). Any precise dollar figure attached to an I-16 today is, in practice, guesswork.