Mikoyan-Gurevich I-3

Mikoyan-Gurevich

Company type	Design bureau
Industry	Aerospace, Defense
Founded	1939
Headquarters	Soviet Union
Products	Fighter aircraft prototypes (I-3 series)

The Mikoyan-Gurevich I-3 represented the initial prototype in a series of three closely connected fighter aircraft projects conceived by the Mikoyan-Gurevich design bureau within the Soviet Union during the mid to late 1950s. This sequence began with the I-3, proceeded to the Mikoyan-Gurevich I-7, and culminated in the Mikoyan-Gurevich I-75. Throughout these programs, airframes were frequently modified or repurposed either within a single project or carried forward into subsequent developments. The entire I-3 series experienced setbacks due to delays in the advancement of the Klimov VK-3 afterburning bypass turbojet engine, which was ultimately discontinued and supplanted by the Lyulka AL-7F turbojet.

Design and development

On June 3, 1953, the Council of Ministers commissioned both the I-3 and I-3P models—the former intended as a frontline fighter and the latter designed as an all-weather interceptor. These two variants were developed concurrently alongside the I-1/2 project; however, aside from sharing a similar wing configuration, they bore no design relationship. Visually, the I-3 bore a strong resemblance to the Sukhoi S-1 (prototype of the Su-7), suggesting they may have originated from shared design requirements and foundational research. When compared with the Mikoyan-Gurevich MiG-19, the I-3U was marginally larger and heavier but maintained comparable aerodynamic characteristics.

I-3 (I-380)

Compared to the I-1, the I-3 featured an extended forward fuselage, with the cockpit situated further forward relative to the 60-degree swept wing. Its armament included three 30 mm Nudelman-Richter NR-30 cannons, each supplied with 65 rounds—one mounted in the left wing root and two positioned on the right wing. The Klimov VK-3 turbojet engine was neither installed nor prepared for integration on this airframe. In 1956, the I-3 underwent modification to become the I-3U.

I-3P

Conceived concurrently with the I-3, this variant was equipped with the Almaz search radar identical to that used on the I-1. It carried two 30 mm Nudelman-Richter NR-30 cannons as its primary weapons. Additionally, it could be armed with two ORO-57K rocket launchers, each capable of deploying 16 unguided 55 mm ARS-57 (S-5) rockets, or alternatively two 190 mm TRS-190 rockets, two 212 mm ARS-212 rockets, or two bombs weighing up to 250 kg mounted on pylons beneath the wings. Development of the I-3P ceased by late 1954.

I-3U (I-5)

The I-3U was a conversion of an incomplete I-3 airframe; its fuselage length was increased by 93 cm (from 12.27 m to 13.20 m), and its nose was redesigned to house the Uragan-1 fire control system—hence the "U" in its designation—positioned above the air intake. The inlet cone incorporated an Almaz search radar capable of detecting and tracking targets up to 17 km away. Its weaponry comprised two 30 mm Nudelman-Richter NR-30 cannons equipped with symmetrical automatic ranging linked to the radar system. This variant marked Mikoyan-Gurevich's initial use of titanium alloys in the rear fuselage sections subjected to high thermal loads. The transformation from I-3 to I-3U was finalized in 1956.

Flight evaluations were conducted intermittently between 1956 and 1958 due to recurring engine issues and ongoing modifications. A total of 34 test flights took place, during which design bureau test pilot Georgiy Mossolov achieved a top speed of 1960 km/h at altitude on one occasion. Ultimately, the program was terminated on June 17, 1958.

External links

• http://wp.scn.ru/mig_okb/planes-exp-i380 Archived 2012-05-10 at the Wayback Machine
• http://wp.scn.ru/mig_okb/planes-exp-i410 Archived 2012-05-24 at the Wayback Machine
• http://wp.scn.ru/mig_okb/planes-exp-i420