Why the I-185 Was the Best Soviet Fighter You Never Heard Of

This video explores one of World War II’s most promising, yet overlooked fighters: the Polikarpov I-185. Designed by legendary aircraft engineer Nikolai Polikarpov, the I-185 was a machine ahead of its time, boasting exceptional speed, agility, and firepower. We’ll dive into its ambitious development, cutting-edge technical features, rigorous testing, and the complex wartime decisions that kept it from ever reaching mass production.

Fast, agile, and heavily armed, the Polikarpov I-185 had the makings of a legend. When it first flew in early 1941, it represented the pinnacle of Nikolai Polikarpov’s fighter lineage – the culmination of nearly two decades of innovation that began with the I-1 in 1923. In testing, the I-185 achieved an astounding top speed of 426 mph (646 km/h). Even when weighed down with three 20mm cannons, Soviet test pilots in late 1942 and early 1943 declared it superior to anything they had ever flown, outperforming both domestic and foreign aircraft, including those of the Luftwaffe.

By all rights, it should have been one of the greatest fighters of World War II. But fate and faulty engines had other plans. Despite glowing reports and calls for mass production, the I-185 never made it beyond the prototype stage. This is the story of how one of the most promising aircraft of its era became a forgotten footnote in aviation history.

Built with a sleek plywood monocoque fuselage and an ultra-thin all-metal wing, the Polikarpov I-185 was a perfect blend of strength, speed, and aerodynamic refinement. Thanks to its carefully designed flaps and wing profile, it handled beautifully, a stark contrast to its predecessor, the I-16, which, despite its combat prowess, was notorious for its unforgiving flight characteristics and high accident rate.

Initially, the aircraft was intended to be powered by the promising 2,000-horsepower Tumansky M-90 radial engine. But when the first unit arrived, it failed to meet expectations so drastically that engineers calculated the plane wouldn’t even lift off the ground. Undeterred, Polikarpov reworked the prototype to accommodate another developmental engine – the M-81, which finally allowed the I-185 to take flight on January 11, 1941.

Even so, the M-81 proved unreliable and was soon abandoned. But Polikarpov refused to give up. Anticipating setbacks, he had already begun constructing two more prototypes- one fitted with the Shvetsov M-71, the other with the M-82A. Both variants also carried a formidable punch: three 20mm cannons, giving the I-185 the kind of firepower that could tear through any opponent of its day.

Following the successful Air Force Institute trials, the I-185 was sent to the front for combat evaluation with the 728th Fighter Regiment. Restrictions were strict. Pilots were forbidden to fly over enemy lines to prevent the aircraft from being captured, but even under these limits, the I-185 earned glowing praise.

The pilots were unanimous: every version of the aircraft outperformed any enemy fighter they encountered, while remaining remarkably easy to handle.

To them, the I-185 wasn’t just good, it was the best fighter in the sky. Yet, despite these stellar reviews, no production order ever came. So what went wrong?

The most immediate reason was the cancellation of the M-71 engine program, which effectively killed off the most powerful version of the I-185. Meanwhile, the Lavochkin La-5,  a modified LaGG-3 using the more reliable M-82 engine, was already moving rapidly through development. Since the LaGG-3 was in mass production, converting existing lines to build La-5s was far quicker and more practical than starting from scratch with the I-185.

There were also material concerns. The I-185’s advanced wing structure relied on scarce light alloys- resources the Soviet Union simply couldn’t spare in wartime. The Lavochkin, by contrast, used mostly wood and could be built cheaply and quickly in dispersed factories. In the end, the I-185’s brilliance wasn’t enough to overcome the harsh realities of war. It was a masterpiece that came too late, outshining not by performance, but by practicality.