The Polikarpov I-16 Fighter


Between 1930 and 1935, a new generation of fighter aircraft began to appear in European air forces. Classic biplanes with open cockpits gave way to monoplanes with enclosed cockpits and retractable landing gear. These new fighters carried heavy machine guns and sometimes cannons as well, and often provided armor for the pilot and the engine. The Soviet I-16, designed by Nikolai N. Polikarpov, was the first of this new generation of fighters; it served well during the Spanish Civil War, but soon the newer fighters surpassed it, and by 1941, it was outclassed.

During World War I, the first true fighters were monoplanes, the Fokker Eindeckers. Subsequent experience in the Great War favored biplanes, however, and this preference prevailed for more than a decade after the war. Monoplanes remained in civilian use, particularly in high-performance flight. Some developers retained an interest in monoplanes for military use, as well, for the same reason.

One of these developers was Nikolai Nikolaevich Polikarpov, who began his career as a designer of military aircraft when he was a student in 1916. He continued his work after the Soviets took power, and established his credentials with an adaptation of the de Havilland DH4. In 1922, Polikarpov began work on the IL-400, which was meant to be a monoplane fighter. The idea came from a captured monoplane of German origin, although Polikarpov did not seek to emulate the latter’s metal construction, building his prototype with a wooden frame and fabric skin. The project took its name from the Russian word Istrebitel’, which means “fighter,” and the designation of the engine, L-400. The early versions were not successful, but by 1925 this line of research had resulted in models that were accepted by the Soviet air force, the VVS.

Development slowed for a few years, reflecting organizational changes that accompanied Stalin’s policy shifts as he secured power, but 1929 brought a radical departure in Polikarpov’s career. He was one of several leading aircraft designers who were accused and convicted of high crimes in order to bring them together in a controlled environment with the understanding that their very lives were on the line. In this context, Polikarpov built a biplane fighter, the I-5, that met Stalin’s approval, and in 1931, he was freed from the prison design context, although he was not officially exonerated until after Stalin’s death.

Over the next several years, Polikarpov designed a number of fighters, both monoplane and biplane, reflecting the intention of the VVS to employ both kinds of aircraft for a balanced force. Accordingly, Polikarpov produced an updated version of the I-5, which entered service as the I-15, while working on a monoplane that would also pass muster. Conceptual work began as early as 1932, but construction and testing proceeded the following year.

This new design, which would become the I-16, had none of the glamour of the most famous fighters of World War II. To make the plane as light as possible, it was built with a short length of less than 20 feet. With its radial engine and large tail fin, this gave the fighter a stubby appearance. Its center of gravity made it much more maneuverable than its appearance would suggest, but these same characteristics required a fair amount of work on the part of the pilot to keep the plane steady.

In its construction, the I-16 continued the tradition of wood and fabric, mainly because Soviet industry had not reached the point at which it could sustain the production of metal-skinned aircraft in any meaningful numbers. It was meant to be powered by an imported Wright Cyclone engine, although the contract had not yet been concluded when the I-16 was approved, and a less impressive domestic engine was used in the first models.

In two important respects, it represented a substantial departure from other aircraft. The first major development was its enclosed cockpit. It had a glass canopy that could be slid back when the pilot was secure in his seat; ironically, the benefit of this feature was often lost, as the glass proved difficult to keep clean, and many pilots had the canopy removed altogether, retaining only a frontal windscreen, as many photographs of the plane will demonstrate. The other new feature was the ability to retract the landing gear up into the wings, making the plane more aerodynamic. To raise or lower the landing gear, the pilot had to crank it into position manually, which added to his difficulties in keeping the plane steady in flight. Still, for a few months in 1935, the I-16 was the most advanced fighter in the world, and Stalin proudly permitted it to be displayed at an air show held in Milan that October.

Soon after, I-16 fighters were also delivered to the Republican side in Spain as part of the Soviet Union’s support for the Popular Front. The original delivery consisted of 278 examples, and the Republican side was permitted to produce I-16’s of their own. Although the I-15 was even more numerous than the I-16, the latter’s numbers made it an iconic part of that war, earning different nicknames on either side of the conflict. Republican forces dubbed the I-16 the “Fly,” or Mosca, while Nationalists called it “Rat,” or Rata. It outperformed the German Heinkel He 51, was comparable to the Italian Fiat CR.32, but inferior to the German Messerschmitt Me 109.

Its greatest liability in these early combats was a relatively light armament of only two machine guns. Just as later versions of the I-16 were outfitted with more powerful engines, so too were they given stronger armament. At first, the number of machine guns was doubled to four by installing two in the fuselage along with the two in the wings. Later, the machine guns in the wings were replaced by 20mm cannons, further increasing the firepower. Bombs could be carried under the fuselage, or rockets could be carried under the wings as well.

Both of Polikarpov’s major fighter types were lent to the Nationalist Chinese when the war with Japan started in 1937. 1939 gave them the opportunity to fight for the Soviet Union directly, when they participated in the Soviet campaign against Japan at Khalkhin-Gol. In the latter case, the I-16 enjoyed one more record-making moment when a flight of I-16’s, armed with rockets intended for ground attack, fired instead at Japanese planes and shot down two.

The latter incident draws attention to the fact that the I-16 was often sent into action in order to serve in a ground-attack role, instead of an air-superiority role. It was officially designated as a fighter (Istrebitel’), but it performed well in ground attack. This became particularly clear during with Winter War with Finland, when it achieved air superiority through ground attacks on enemy airfields. There may be a suggestion of its general-purpose nature in the prevailing Russian nickname for the aircraft, ishachok or “little donkey,” which was initially suggested by the Russian pronunciation of the designation I-16.

By 1941, the I-16 was clearly inferior to German fighter craft, which had been honed by the experience of the Battle of Britain. Newer planes were in development, but it took time to deliver production models, so I-16’s still served, although production had been curtailed in 1940. Nearly forty percent of Soviet fighter craft on the western airfields were I-16’s when the German invasion came. Many of these were destroyed on the ground, in much the same way that I-16’s had destroyed Finnish aircraft in their raids on airfields. Those that made it into the sky fared little better, although the I-16’s maneuverability offered some chance. Reportedly, fifteen I-16’s brought down enemy planes by flying into them, a tactic that was usually fatal for the pilot employing it.

Despite its disadvantages, the I-16 could not be replaced with more modern types in any numbers until the summer of 1942. During the fall, the surviving I-16’s were withdrawn for service as training vehicles. More than 6500 I-16’s had been produced. Until his death in 1944, Polikarpov, known popularly as the “King of Fighters,” struggled to modernize the I-16 with prototypes of the I-180 and I-185, but testing difficulties prevented the acceptance of either of these designs.

Polikarpov’s I-16 was a groundbreaking fighter craft when it first appeared, and it performed well in the early conflicts in which it served. In some ways, however, it was relatively primitive even when it appeared, and soon the fighter craft of friend and foe alike surpassed it. When the German invasion came, its numbers alone kept it in use until newer planes were available.



Crosby, Francis.  The World Encylopedia of Fighters & Bombers.  Anness Publishing, 2010

Gordon, Yefim.  Polikarpov I-16 Fighter – Red Star Vol. 3.  Midland Publishing, 2002

Jackson, Robert, et al.  Aircraft: Compared and Contrasted.  Amber, 2010

Ibid., ed.  The Encyclopedia of Aircraft.  Thunder Bay Press, 2004

Winchester, Jim.  Classic Military Aircraft: The World’s Fighting Aircraft 1914-1945.  Amber, 2013


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