Mikoyan-Gurevich DIS

Mikoyan-Gurevich DIS
Company type	Aircraft prototype
Industry	Aerospace
Founded	1940
Founder	Mikoyan-Gurevich design bureau (OKB)
Defunct	1943
Headquarters	Soviet Union
Products	Heavy fighter aircraft prototype (DIS, MiG-5)

Template:Good article Template:Infobox aircraft The Mikoyan-Gurevich DIS (Russian: Дальний истребитель сопровождения/ Dalnij Istrebitel' Soprovozhdenya, meaning "long-range escort fighter") was a Soviet heavy fighter prototype developed during World War II, primarily designed for the escort fighter mission. The designation MiG-5 was assigned to the planned production model. Within the USSR, it competed against designs such as the Grushin Gr-1, Polikarpov TIS, and Tairov Ta-3.

Plans included variants for reconnaissance and bombing roles; however, these were halted by the onset of Operation Barbarossa in June 1941. The program was ultimately unsuccessful due to underperforming Mikulin AM-37 powerplants. When a second prototype was fitted with M-82 radial engines, its capabilities remained unimpressive. After constructing at least two prototypes, the project was terminated in 1943.

Design and development

On 7 October 1940, the NKAP (Narodnyy komissariat aviatsionnoy promyshlennosti—People's Commissariat for Aircraft Industry) commissioned the OKO (opytno-konstruktorskiy otdel—Experimental Design Department) of Factory No. 1, which would later evolve into the Mikoyan-Gurevich design bureau (OKB), to develop a twin-engine, long-range, single-seat escort fighter powered by the then-in-development AM-37 engine from Mikulin. The ministry required that preliminary specifications and a scale model be ready for review by 12 November 1940. Shortly thereafter, Mikoyan and Gurevich received orders to produce three prototypes scheduled for State acceptance trials on 1 August, 1 September, and 1 November 1941. Following this directive, NKAP expanded the aircraft’s intended roles to include bombing, torpedo attacks, reconnaissance, and interdiction.

The DIS featured a low-wing monoplane configuration with twin engines and twin vertical stabilizers. Its structure combined different materials: the forward fuselage was constructed from duralumin; the central fuselage section utilized a wooden monocoque design; and the aft fuselage consisted of steel tubing covered with duralumin skinning. The twin tail units were wooden and incorporated an electrically actuated variable-incidence horizontal stabilizer. The elevators had duralumin frames covered in fabric. The wing assembly comprised three parts: a metal center section and wooden outer panels with fabric-covered ailerons and veneer-covered Schrenk flaps. Leading-edge slats extended over two-thirds of the wing span. The main landing gear retracted rearward into the engine nacelles’ aft sections, while the tailwheel folded into the rear fuselage. The Mikulin AM-37 inline engines were mounted beneath the wings, with oil coolers installed within the outer wing panels. Supercharger air intakes were positioned along the leading edges of the wings. For enhanced downward visibility, the pilot’s cockpit featured a glazed panel under the nose. Protective armor plating up to 9 mm (0.35 in) thick shielded the pilot’s front, rear, sides, and seat underside. Fuel was stored in two armored tanks behind the cockpit holding 1,920 litres (422 imp gal; 507 US gal), plus four additional tanks located within the wings.

Armament plans initially called for a 23 mm (0.91 in) VYa cannon mounted in a pod beneath the nose with 200 rounds available; however, the VVS favored equipping the aircraft with two Taubin MP-6 cannons carrying 120 rounds each. Due to reliability issues with these weapons, development reverted to using the original VYa cannon instead. Each wing root housed a synchronized 12.7 mm (0.50 in) Berezin UBS machine gun loaded with 300 rounds, positioned above two 7.62 mm (0.300 in) ShKAS machine guns carrying 1000 rounds apiece. The gun pod could be detached to allow for bomb loads up to 1,000 kg (2,200 lb) or alternatively fitted to carry a torpedo.

Flight testing

The initial prototype, designated internally as T, completed its maiden flight on 11 June 1941. Manufacturer-conducted flight trials from 1 July to 5 October yielded unsatisfactory results, as the aircraft achieved a maximum speed of only 560 km/h (348 mph) at 7,500 metres (24,606 ft), falling short by 104 km/h (65 mph) compared to expectations. To address this, the original three-bladed 3.1-metre (10 ft) AV-5L-114 propellers were replaced with four-bladed 3.1-metre (10 ft) AV-9B-L-149 propellers, and the engine installation was reconfigured following wind tunnel analyses at TsAGI (Central Aero and Hydrodynamics Institute). These tests identified poorly designed engine components as the primary source of excessive drag. After these adjustments, the aircraft's speed improved to 610 km/h (380 mph) at an altitude of 6,800 metres (22,310 ft), with a climb time to 5,000 metres (16,404 ft) of 5.5 minutes. Despite these enhancements, the LII (Lyotno-Issledovatel'skiy Institoot—Flight Research Institute) did not endorse mass production but recommended ongoing development and testing. The German advance toward Moscow in October 1941 compelled the Institute and DIS to relocate to Kazan, while the OKO and its manufacturing facility moved to Kuibyshev. The failure of the AM-37 engine to enter production temporarily stalled the project.^[1]

In May 1941, all aircraft designers, including OKO, were instructed to adopt the Shvetsov ASh-82 radial engine as an alternative powerplant for their designs. However, evacuation disrupted production of this variant, internally named IT, which was not constructed until autumn 1942. Apart from the engine swap, it featured minor differences from the T model: its tailcone was split vertically to function as an air brake, and its armament was updated to include two VYa cannons mounted in an undernose pod with 150 rounds each, supplemented by four Berezin UBK machine guns positioned in the wing roots. The IT undertook its first flight on 28 January 1943, reaching a top speed of 604 km/h (375 mph) and climbing to 5,000 metres (16,404 ft) in 6.3 minutes. Flight trials ceased on 10 February due to issues with floatless carburetors that required adjustment at TsIAM (Tsentrahl'nyy Institoot Aviatsionnovo Motorostroyeniya—Central Institute of Aviation Motors). Persistent problems with these carburetors caused delays that ultimately led to the project's cancellation in October 1943.^[2]

The designation MiG-5 was reserved for the production variant of this aircraft, as indicated by an NKAP directive dated 2 October 1941 ordering Zavod No. 1 to commence manufacturing following successful State acceptance tests. Additional designations associated with this aircraft include DIS-200 and Idzeliye 71, its factory code. Had a bomber variant reached production, it might have been designated MiG-2.^[2]

While two prototypes are confirmed to have been constructed, some documentation suggests additional units may have been built. The initial contract called for three aircraft and was later amended to include two more equipped with M-82 engines. Certain sources cite first flight dates for this latter version as January 1942 and 15 October 1941; these discrepancies could imply that two such aircraft were completed or may simply reflect record-keeping errors.^[3]

Variants

DIS – standard model designation
DIS-T – initial experimental version powered by two Mikulin AM-37 inline engines, each delivering 1,400 hp
DIS-IT – second experimental variant equipped with two Shvetsov M-82F radial engines rated at 1,700 hp each; incorporated additional refinements for enhanced performance
MiG-5 – designated by the Soviet Air Forces for production-standard aircraft, though this designation was never applied

Specifications (DIS-T)

File:MiG5 (DIS-200).png

MiG5 (DIS-200)

Template:Aircraft specs

Comparable aircraft

References

↑ Gordon, pp. 126, 128
↑ ^2.0 ^2.1 Cite error: Invalid <ref> tag; no text was provided for refs named Gordon
↑ Gordon, pp. 129–30