Aviation of Word War II
Aircraft Armament of the I-16
As a result of the war in Spain, one of the main shortcomings of the I-16 was still recognized as its insufficient firepower. The main enemy of the Mosca, the Italian Fiat C.R.32 fighter, quickly proved the high efficiency of its airborne weapons. And this is with clearly the worst flight characteristics.
It became clear that the two ShKAS 7.62 mm machine guns, despite their record rate of fire (1800 rounds per minute), are insufficient fighter weapons. The order for the additional equipment of the I-16 went to the Soviet Union. The revision of the machine was carried out at the plant number 21 by a team of engineers under the guidance of designer Borovkov during one night. They installed a third synchronous ShKAS at the bottom of the fuselage. The plane was tested the very next day. The vehicle received the designation I-16 type 6 and was produced in an amount of 30 copies. The planes were urgently flown by a brigade of military test pilots and just as urgently sent to Spain. A little later, a modification appeared with two synchronous ShKAS machine guns mounted in the upper part of the fuselage. This four-machine-gun I-16, designated Type 10, was called in Spain "Super Mosca" or simply "Super". The urgency of the order led to the fact that this type continued to be refined in the process of serial construction and in its final form - with an uprated M-25V engine, landing flaps and retractable skis, it passed state tests at the Air Force Research Institute only in February 1939.
Type 10 entered Spain for the first time in March 1938 in the amount of 31 copies. During the summer, another 90 of these four-machine-gun vehicles arrived. These aircraft took part in air battles during the summer and autumn of 1938. During this period, 24 "contraband" American high-altitude engines "Wright-Cyclone" F-54 got to Spain. These engines were used to equip the aircraft of Squadron No. 4, consisting of 12 I-16 Type 10, commanded by one of the most productive Spanish pilots Antonio Arias. Supers, equipped with an engine that developed maximum power at 7000 meters, had an excellent opportunity to win back on the German Bf.109 fighters. It must be said that already the first combat clashes between I-16 and Bf.109 in the spring of 1937 showed approximately equal capabilities of these machines. However, this continued only up to 3 km altitude, where the power of the I-16 engine began to drop, and the Bf.109 engine retained power until it climbed to an altitude of 5000 meters. This advantage allowed the Messerschmitt pilots to almost always take a more advantageous position. After installing high-altitude engines on the planes of the 4th squadron, the pilots began to fly with oxygen masks, for which they were nicknamed the squadron of "suckers".
The I-16 type 17 aircraft was an I-16 type 10, on which the ShKAS wing machine guns were replaced by the ShVAK cannons. The slug belts were laid along the center section spars at the level of frame No. 1 of the fuselage. In the places where the guns were installed, the wing structure was reinforced, the removable panel for access to the gun had dimensions of 650 × 774 mm.
The I-16 fighter was armed with the pride of the Soviet industry - ShKAS machine guns with a rate of fire of 1800 rounds per minute, but the gunsmiths did not rest on their laurels. In 1937, the creators of the ShKAS Shpitalny and Komaritsky proposed an ultra-SHKAS with a rate of fire of 2400 rounds per minute. Before the test firing of the ultraShKAS began, two engineers, Savin and Norov, presented in 1935 for testing one more CH aircraft machine gun with a rate of fire of 2800-3000 rounds per minute. In 1936, the machine gun successfully passed firing tests, and in 1937 it was recommended for mass production. I-16 fighters were immediately armed with CH machine guns; The I-16s with SN machine guns received the designation type 19, despite the fact that, apart from the armament, the aircraft was no different from the I-16 type 10. The wing-type ShKAS machine guns were replaced by SN machine guns, while the synchronous machine guns remained the same - ShKAS. At the beginning of 1939, plant number 21 produced three I-16 type 19 (serial numbers 1921111, 19212 and 19213). From March 17 to March 26, the planes were tested by the factory test pilot Thomas Susi. Based on the test results, it was recommended to build a batch of such aircraft. But mass production was considered impractical. The fighters were transferred to the Air Force under the designation I-16SN. In the spring of 1939, the ultraShKAS aviation machine gun was adopted by the Red Army Air Force. The fighters, armed with ultra-SHKAS and CH, took part in the war with Finland in the winter of 1939-1940.
The possibility of installing a larger caliber weapon on the fighter was studied. These works were carried out in the winter of 1938-39. at the plant number 156 in Moscow personally under the leadership of Nikolai Nikolaevich Polikarpov. Mainly, methods of mounting synchronous heavy machine guns over the engine were considered. Installing heavier machine guns in the nose of the aircraft would allow the glider's center of gravity to be shifted forward, thereby increasing the pitch stability margin, which, in turn, made the aircraft a more stable platform when firing. At the end of 1939, two fighters taken from the aviation brigade stationed in Lyubertsy began to be modified for large-caliber machine guns. On one aircraft (serial number 1021332), wing ShKAS were dismantled, and two 12.7-mm machine guns of the Berezin design were installed in the nose of the fuselage just below the axis of the aircraft. The placement of machine guns and boxes for ammunition (440 rounds) led to the need to reduce the capacity of the fuselage fuel tank. The total capacity of the tanks was kept at the same level due to the installation of wing tanks. The aircraft received the designation I-16SO (Synchronized Experienced). The tests were carried out from March 23 to April 9, 1939. The variant with two 20-mm ShVAK cannons received the designation I-16PS (Cannon Synchronized), the tests of this aircraft were carried out in parallel with the tests of the I-16SO. The guns were mounted on an aircraft with serial number 521570; they were so long that the breeches of the guns protruded into the cockpit. Ammunition - 175 rounds per barrel. Externally, the I-16SO and I-16PS were almost identical to the original aircraft. Both fighters successfully passed tests, during which they even fired weapons with the stabilizer turned off. Aircraft have proven their ability to fly with propeller blades shot through. On the other hand, the tests revealed drawbacks, the main of which was the ingress of powder gases into the cabin and into the engine carburetor. On a cannon-type aircraft, this defect manifested itself more clearly, therefore, an option with Berezin machine guns was recommended for mass production.
It is not known whether a series of fighters with Berezin machine guns was built (in the technical documentation, the aircraft were designated TsKB-150), but in the spring of 1939 these machines aroused considerable interest. Ultimately, at the highest level, this modification was recommended for mass production, and the development of this option was given the highest priority at all factories that produced I-16 fighters. The delay in the release of aircraft was associated with a shortage of machine guns - the arms factories did not have time to produce them in sufficient quantities. The mass production of the I-16 with machine guns BS (Berezin Synchronous) began in mid-1940, the fighter was designated I-16 type 29.
I-16 type 29 with the M-63 engine was the last modification of the fighter. The composition of the armament has been changed - there are no wing machine guns, in addition to 2 SHKASOV, a BS machine gun of 12.7 mm caliber is installed at the top of the fuselage in the lower part of the fuselage.