Category Mig

1-250 / N

In early 1944 the GKO (state committee for defense) “gave comrades Yakovlev, Lavochkin, Mikoyan, and Sukhoi the responsibility to build jet aircraft.” During the meeting held in Mikoyan’s office to discuss this project, all the department managers (who knew very well that the USSR did not have a jet engine in production) decided to power their new fighter with a package unit consisting of a piston engine—a 1,214- kw (1,650-ch) VK-107A—and a special booster nozzle designed at the central institute for aeroengine construction (TsIAM) by a team led by Professor К. V. Kholshchyevnikov. In this rather odd assembly, the power delivered by the piston engine was shared between two “con­sumers": a propeller 3.1 m (10 feet, 2 inches) in diameter, and a com­pressor intended to feed a combustion chamber. This assembly was known as a VRDK (Vozdushno-Reaktivmy-Dopolnitelniy Kompressor: jet – propelled auxiliary compressor) or booster. For takeoff and cruise situ­ations, the main consumer was the propeller. During these flight modes the compressor (driven by a reduction gear) ran at idle, and no fuel was pumped into the seven burners of the combustion chamber When dash speed was needed fuel was injected into the burners and ignited by spark plugs. The compressor was then clutched at its maxi­mum speed, and the revolution speed of the propeller was reduced. This power package offered a total of 2,061 kW (2,500 ch) at 7,000 m (22,960 feet) that is, 1,067 kW (1,450 ch) from the VK-107A at rated power and 994 kW (1,350 ch) from the VRDK equivalent.

It was also possible to regulate the VRDK power by means of the adjustable nozzle at the rear of the combustion chamber. This nozzle was fitted with two eyelids controlled by hydraulic jacks. The VRDK was cooled by a water-vapor system that protected the fuselage struc­ture and the cockpit against overheating. The water tank had a capacity of 78 1 (20.6 US gallons). The VRDK and the VK-107Aboth ran on gaso­line. The VRDK operated like the compressor’s second stage of a super­charged piston engine, increasing the aircraft’s ceiling.

The wing had a trapezoidal planform and a thin profile. The fuel system was made up of three self-sealing bladder tanks, one in the fuselage in front of the cockpit (412 1 [109 US gallons]) and two in the center section of the wing (100 1 [26 US gallons] each). The main gear

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The first 1-250 prototype or N-l was rolled out on 26 February 1945 just eleven months after the project received the go-ahead.

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The 1-250 combined power unit (J) Oil cooler (2) Engine exhaust pipe (3) VK-107A piston engine (4) Fuel tanks of 412 and 200 1 (5) Engine supercharger air-bleed. (6) Reduction gearbox (7) Compressor drive shaft (8) Compressor (9) Water jacket. (JO) Fuel injectors (JJ) Combustion chamber. (J2) Adjustable-area nozzle.

was of the levered-suspension type with lower arms leading the leg. The most original features here were the doors, which permanently closed the wheel wells except at the very moment of the gear retrac­tion or extension (a first in the USSR).

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Left to right: the VK-107A engine, the compressor drive shaft, and the VRDK compres­sor

The N-l prototype was armed with three 20-mm ShVAK (G-20) cannons—one mounted between the cylinder blocks and bring through the propeller hub, the others flanking the engine. Each of these weapons could Are 100 rounds, a flgure eventually improved to 160.

The preliminary design of the 1-250 was approved on 28 March 1944. At the same time, Sukhoi set to work on a similar aircraft, the Su-5 (1-107), which also had a combination power plant. But its performance was disappointing, and flight tests of the Su-5 were stopped on 15 July 1945. On 26 October 1944 the full-scale 1-250 mock – up was examined in great detail and endorsed; on 30 November almost all the sets of drawings were complete. As the war continued into 1945, OKB officials elected to build not an experimental prototype but instead an operational combat fighter.

Deputy chief engineer M. I. Guryevich had this to say in the OKB house newsletter:

We are now starting work on the N, an entirely new type of air­craft that greatly departs from our previous designs. We are going to reach speeds never achieved before. We are going to use new formulas, new materials. We shall have to create new systems. There is not a single sector, a single department of our OKB that will escape the difficult problems we shall have to face. We must give up all of the old configurations and all of the systems we are

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1-250 (N-l); the dotted line shows the modified fin (MiG ОКБ three-view drawing)

used to and create new ones. We are forging ahead in a new way, the only one enabling us to achieve levels that have never before been attained and that we could hardly have dreamed possible.

The N-l was rolled out on 26 February 1945, less than one year after the project received the go-ahead, and the N-2 followed three months later. The initial prototype was first flown on 3 March 1945 by A. P. Deyev, and the VRDK was fired as early as the third flight. The

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increase in speed proved to be significant: it was about 100 km/b (54 kt) faster than the best piston-engine fighter flying at the time. The only modification made involved a slight increase of the fin area.

In mid-May 1945 Deyev was killed during a flight test. The struc­tural load factor was somehow exceeded, and the tailplane disintegrat­ed at an altitude far too low for the pilot to bail out. The N-2 trials were conducted by a pilot from the LII, A. P. Yakimov, and later by two young ОКБ pilots, A. N. Chemoburov and I T Ivashchenko. During the first stages of the factory tests, the N-2 remained unarmed Flight tests showed that, at top speed, the plane’s yaw stability was inade­quate. The fin area was increased accordingly. Takeoff roll was limited to 400 m (1,310 feet) with the VRDK in operation; but otherwise it took far too long to become airborne owing to the propeller’s small diame­ter. The N-2 was destroyed during a crash landing, with Chernoburov at the controls.

In June 1945 the production factory was instructed to build ten I- 250s in time for a Red Square flyover on 7 November in celebration of the twenty-ninth anniversary of the October Revolution. ОКБ test pilot I. T. Ivashchenko organized an accelerated training program for a batch of air force pilots under the command of Col. P. F. Chupikov. Nine I-250s were completed in time; unfortunately, the weather was so bad in Moscow on 7 November that the flyover had to be canceled.

Sixteen I-250s were delivered in record time to Baltic fleet aviation units at Skultye, near Riga. The first production I-250s had saber­shaped propeller blades; they were replaced later on by conventional

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The 1-250 N-l in 1945 with the larger fin.

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The N-2 the second 1-250 prototype, was rolled out in 1945 The fin was modified once more, and the tail wheel no longer retracts This aircraft was painted dark blue and embellished with a yellow streak.

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This photograph of the N-2 shows the adjustable-area nozzle, two eyelids controlled by hydraulic jacks.

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The production version of the 1-250 is sometimes referred to as the MiG-13. In fact, only sixteen aircraft of the type were delivered to the Baltic fleet aviation units.

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The air intake duct for both the engine supercharger and the VRDK is visible below the engine mount of the MiG-13 Note also the saber-shaped blades of the propeller.

blades. The production 1-250 with serial number 3810102 (381 = facto­ry number, 01 = first series, and 02 = second machine in the series) passed its factory tests in July 1947. Its acceptance trials were carried out at the Nil WS test center between 9 October 1947 and 8 April 1948 with I. M. Sukhomlin at the controls.

All production I-250s—referred to as MiG-13s in some ОКБ docu­ments—were withdrawn from service in May 1948.

The following details refer to the 1-250 N-l.

Specifications

Span, 9.5 m (31 ft 1.9 in); length, 8.185 m (26 ft 10.2 in); wheel track, 2.75 m (9 ft 0.3 in); wheel base, 4.995 m (16 ft 4.6 in); wing area, 15 m2 (161 5 sq ft); empty weight, 2,587 kg (5,702 lb); takeoff weight, 3,680 kg (8,110 lb); fuel, 450 kg (992 lb); oil, 80 kg (176 lb); water, 78 kg (172 lb), wing loading, 245 kg/m2 (50.2 lb/sq ft); max operating limit load factor, 6.5.

Performance

Max speed, 825 km/h at 7,000 m (446 kt at 22,960 ft), max speed at sea level, 620 km/h (335 kt); climb to 5,000 m (16,400 ft) with VRDK in 3 9 min, without VRDK in 4.6 min; service ceiling with VRDK, 11,960 m (39,230 ft), without VRDK 10,500 m (34,440 ft); landing speed, 150 km/h (81 kt); range with VRDK, 920 km (570 mi), without VRDK 1,380 km (857 mi); takeoff roll with VRDK, 400 m (1,310 ft); landing roll, 515 m (1,690 ft).

The following details refer to the production 1-250 (MiG-13)

Specifications

Span, 9.5 m (31 ft 1.9 in); length, 8.185 m (26 ft 10.2 in); wheel track, 2.75 m (9 ft 0.3 in), wheel base, 4 995 m (16 ft 4.6 in); wing area, 15 m2 (161.5 sq ft); empty weight, 3,028 kg (6,674 lb); takeoff weight, 3,931 kg (8,664 lb); fuel, 590 kg (1,300 lb); oil, 80 kg (176 lb); water, 78 kg (172 lb); wing loading, 262.1 kg/m2 (53.7 lb/sq ft).

Performance

Max speed not recorded; unstick speed, 200 km/h (108 kt); landing speed, 190-195 km/h (103-105 kt).

1-211 / Ye

As mentioned earlier, this program was a direct result of the 1-210 tests in one of the full-scale TsAGI wind tunnels. The goal was still to pro­long the MiG-3 series with an updated product. But to improve the level and climbing speeds of the aircraft, it was necessary to find a more powerful engine than the M-82A and to reduce its takeoff weight significantly. The only available engine alternative was the M-82F, delivering 1,362 kW (1,850 ch) at takeoff and 979 kW (1,330 ch) at

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The 1-211 marked a new attempt to match a radial engine with the MiG-3 airframe. This time it was a complete success. But, strangely enough, the project was not pur­sued, and Lavochkin inherited most of the technical innovations tested with this machine.

5,400 m (17,700 feet). The 1-211 differed from the 1-210 in several other respects as well. The front fuselage cross section was increased to make the junction of the engine cowling and the fuselage smoother, and the adjustable flaps of the engine exhaust outlet were moved to the sides of the fuselage. The cockpit was moved 245 mm (9.64 inches) back and the fin chord was extended forward, increasing its area and improving the aircraft’s yaw stability. The oil cooler air inlets were moved into the wing root fairings. The shape of the engine cowling was carefully designed to cope with the problem of airtightness and to achieve the best junction possible with the fuselage. All of these modi­fications resulted in an outstanding increase in the aircraft’s speed. In 1942 most of these technical innovations (engine cowling design and airtightness, proper positioning of the engine itself, and the 1-210 wing leading edge slats) were passed on—at the order of the Narkomavprom (state commissariat of the aviation industry)—to the Lavochkin OKB, which adapted them successfully to the La-5, a mass-produced fighter.

The armament was also modified: the 1-210’s machine guns were replaced by two synchronized 20-mm ShVAK cannons at the bottom of engine cowling. Assembly of the 1-211 begai in December 1942 and finished in August 1943. Golofastov was the first pilot to fly it. Two pro­totypes were built, followed by eight preproduction aircraft. The short­comings of the first 1-210 and its engine became nothing more than a bad memory, and the 1-211 proved to be the best Russian fighter of the time. Compared with the 1942 version of the La-5, its level speed was 40 to 166 km/h (21 to 90 kt) higher, depending on the altitude. Com­pared with the 1942 version of the Yak-9, it was 65 to 73 km/h (35 to 39 kt) faster. To climb to 5,000 m (16,400 feet), the La-5 took 1.4 to 2.2 minutes longer, and the Yak-9 0.9 to 1.5 minutes longer. After the pro­totypes passed the factory flight tests, ten preproduction 1-21 Is were delivered to the VVS to prove themselves in combat. They engaged successfully in air battles over the northwestern front near Kalinin. Air force pilots and Nil WS test pilots spoke out in favor of adding the 1-211 to the WS fleet. But in spite of their recommendations and the aircraft’s remarkable flying qualities, the GKO (defense state commit­tee) gave up mass-producing the aircraft because two factories were already building the La-5FN (an La-5 with an ASh-82FN engine)

Specifications

Span, 10.2 m (33 ft 5.6 in); length, 7.954 m (26 ft 1.1 in); height, 3.63 m (11 ft 10.9 in); wheel track, 2.78 m (9 ft 1.4 in); wheel base, 5 015 m (16 ft 5.4 in); wing area, 17.44 m2 (187.7 sq ft); empty weight, 2,528 kg (5,572 lb); takeoff weight, 3,100 kg (6,830 lb); fuel + oil, 385 kg (848 lb); wing loading, 177.75 kg/m2 (36.38 lb/sq ft).

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Performance

Max speed, 670 krn/h at 7,000 m (362 kt at 22,960 ft); climb to 5,000 m (16,400 ft) in 4 min; service ceiling, 11,300 m (37,065 ft); range, 1,140 km (710 mi).

MiG-В / Utka

A few months before the start of World War II, at the dawn of the jet era, members of the MiG design department started to gather and test various ideas for future aircraft. For this purpose, they decided to build an experimental prototype: an unconventional canard, or tail-first, machine (canard is French for duck). This is how Mikoyan and Gurye­vich justified their enterprise in a note enclosed with the preliminary design:

The canard-tailed aircraft we have designed and that is now being built is an experimental machine intended to check the maneuverability and steadiness in flight of that type of aircraft and to verify the characteristics of highly swept wings. We have chosen the pusher-prop formula because it will enable us to check the low-speed handling with a wing that will not be blown by the propeller. This point is of special interest for aircraft pow­ered by jet engines. The Utka ["duck”] will be a useful tool with which to examine thoroughly all the problems of handling, taxi­ing, takeoff, and landing (including go-around and touch-and-go) without any propeller slipstream effects on control surfaces.

In conceptualizing the Utka or MiG-8, the ОКБ project engineers had in mind the installation of a jet engine on an airframe of the same layout so that its hot exhaust gases would keep away from all structural elements. The design was prepared in close cooperation with a team of TsAGI technicians. The MiG-8 had a high wing braced by V-shaped struts with a two-spar fabric-covered wooden structure that displayed a 12 percent constant thickness ratio. The wing’s forward sweep angle was 20 degrees at the leading edge with a 2-degree anhedral. The fuse­lage, fins, rudders, and canard surfaces were made of wood.

The Utka was fitted with a fixed tricycle landing gear (a first for a MiG aircraft). The cabin had room for three people, with the pilot in front. Lateral and forward visibility was excellent because of the high position of the wing and the fact that the engine was in the rear. The engine bay and the fuselage were aerodynamically well matched.

The elevator was controlled by a rod and a bellcrank, while the rudder and ailerons were controlled by cables. The two duralumin fuel tanks had a total capacity of 195 1 (51 US gallons) and were located in the center section of the wing. The 18-1 (4.7-US gallon) oil tank was located behind the cabin. The air-cooled Shvetsov-Okromeshko M-11F radial engine offered 81 kw (110 ch) and was entirely cowled with the

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The vertical tail surfaces were later moved to midspan, and the slots were removed The wing tip anhedral is noticeable.

 

MiG-8 Utka; the two side views show the different locations of the vertical tail surfaces (MiG О KB four-view drawing)

 

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exception of the cylinder heads. The two-bladed, fixed-pitch propeller was made of wood and measured 2.36 m (7 feet, 8.9 inches) in diame­ter. Gear legs were constructed of welded metal with pneumatic shock absorbers; the front wheel (300 x 150 initially) had an oleo strut. The wheels of the main gear (500 x 150) were fitted with pneumatic brakes. Later, the wheel sizes were standardized at 500 x 150. The Utka was flown in 1945 for the first time by test pilot A. I. Grinchik. The two fins were then located at the wing tips, and the leading edge was fitted with protruding slots. The two fins were later moved to midspan. The rud­ders were fitted with balance weights, and the leading edge slots were removed. The ОКБ also tried out wing tips with a strong anhedral.

The MiG-8 was remarkable for its outstanding stability, refusing to spin even when used at great angles of attack. Many OKB pilots such as A. N. Grinchik, A. I. Zhukov, A. N. Chernoburov, and chief engineer E. F. Nashchyekin spent a great deal of time at its controls. Because of its outstanding flying qualities, safety and ease of handling, and low man­ufacturing costs, the OKB tried to sell the aircraft to Aeroflot, hut the offer was not taken into account. The plane served as the design bureau’s liaison aircraft for several years.

Specifications

Span, 9.5 m (31 ft 1.9 in); span of the canard surfaces, 3.5 m (11 ft 5.8 in); length, 6.995 m (22 ft 11.4 in); wheel track, 2.5 m (8 ft 2.4 in); wheel base, 2.996 m (9 ft 10 in); wing area, 15 m2 (161.5 sq ft); empty weight, 642 kg (1,415 lh); takeoff weight, 997 kg (2,197 lb); max take­off weight, 1,150 kg (2,535 lb); fuel, 140 kg (309 lh); oil, 14 kg (31 lh), wing loading, 66.5/76.7 kg/m2 (13.6/15.72 lb/sq ft); aircraft balance, 8% MAC.

Performance

Max speed, 205 km/h (111 kt); landing speed, 77 km/h (42 kt), range, 500 km (310 mi).

PBSh-1 and PBSh-2 Series

PBSh-1

Throughout the 1930s the doctrines relating to the use of big armored units were completely reappraised. Because every new threat demand­ed an immediate answer, a new type of aircraft appeared in the USSR: the shturmovik, or assault aircraft. Several of the best-known aircraft manufacturers worked on this new weapon. At the start of the decade Tupolev proposed two heavy shturmoviks, the ANT-17 and ANT-18, but they were never built. The TsKB (central construction bureau) built four aircraft designed by D. P. Grigorovich, the LSh-1, TSh-1, TSh-

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The PBSh-1 main gear was directly inspired by that of the I 200.

2, and ShON. In 1933 a design brigade under the leadership of S. A. Kocherigin—and assisted by the forty-one-year-old M. I. Guryevich, Mikoyan’s future right-hand man—built the TSh-3, also called the TsKB-4. N. N. Polikarpov, for its part, developed the R-ZSh.

All of these attempts led in 1936 to the Ivanov program (“Ivanov” was Stalin’s cable address), an air force initiative that resulted in the construction of such prototypes as the KhAI-5 (R-10) and KhAI-52, designed by Nyeman, winner of the contest; and the ANT-51 and ShB, both designed by Sukhoi. But in the end the true winner was a relative­ly unknown outsider, S. V. Ilyushin. More than 40,000 of its BSh-2s, renamed the 11-2 in 1940, were built because of the war.

Mikoyan and Guryevich started the preliminary design of their first assault aircraft in 1940. The PBSh-1 (Pushechniy Bronirovaniy Shtur – movik. armored assault aircraft with cannons) was a single-seater designed to attack frontline ground targets such as troops, strong points, and armored vehicles. It had a cantilever inverted gull wing and was to be powered by a 1,178 kW (1,600 ch) Mikulin AM-38 engine. Sensitive parts, the engine, and the cockpit would be protected by armor plating. But the weight of the armor alone was 1,390 kg (3,065 pounds), or 30 percent of the aircraft’s takeoff weight. The design had tc be completely reconsidered to integrate the armor into the stressed structure. It was to be equipped with two 23-mm cannons in fairings beneath the wing (96 rpg) and six 7.62-mm ShKAS machine guns on the wing leading edge (750 rpg). All of these weapons would fire out­side the propeller disc.

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The bomber version of the aircraft was to carry in its fuselage either 24 10-kg (22-pound) FAB-10 or 24 8-kg (17.6-pound) FAB-8 bombs and either 280 2.5-kg (5.5-pound) FAB-2.5 or 120 1-kg (2.2-pound) ZAB – 1 bombs. (FAB indicates demolition bombs, while ZAB refers to incen­diary bombs. The number after the acronym reflects the bomb’s weight.) For dive-bombing missions, two FABs ranging in weight from 25 to 250 kg (55 to 550 pounds) could be added beneath the wings.

The preliminary design by N. Z. Matyuk, chief of the aerodynamic design department, was approved on 24 July 1940 by OKO chief engi­neer Mikoyan, his assistant Guryevich, and P. V. Dementyev, manager of Aviakhim factory no. 1. The OKO started work on a full-scale model of the aircraft in the fall. But as soon as the Ilyushin 11-2 was approved for series production, О KB engineers halted all work on the PBSh-1 and started in immediately on the preliminary design for the PBSh-2.

In some OKB documents the PBSh-1 is referred to as the MiG-4.

Specifications

Span, 13.5 m (44 ft 3.5 in); length, 10.145 m (33 ft 3.4 in); height, 3.2 m (10 ft 6 in); wheel track, 2.9 m (9 ft 10 in); wheel base, 6.6 m (21 ft 7.9 in); wing area, 30.5 rrF (328.3 sq ft); takeoff weight, 4,850 kg (10,690 lb); max takeoff weight, 6,024 kg (13,277 lb); wing loading, 159 kg/m2 (32.6 lb/sq ft).

Design Performance

Max speed, 441 km/h at 5,000 m (238 kt at 16,400 ft); max ground speed, 449 km/h (242 kt); range, 900 km (560 mi); service ceiling, 7,600 m (25,690 ft).