Polikarpov I-185

Last updated

Polikarpov I-185
Polikarpov I-185 (M-71).jpg
Side view of the I-185 with a M-71 engine
General information
Type Fighter
National origin Soviet Union
Manufacturer Polikarpov
StatusCancelled
Number built4
History
First flight11 January 1941
Developed from Polikarpov I-180

The Polikarpov I-185 was a Soviet fighter aircraft designed in 1940. It was flown with three engines but all of them were either insufficiently developed for service use or their full production was reserved for other fighters already in production. The I-185 program was cancelled on 27 January 1943. Engines used with the I-185 included the Shvetsov M-71, which was more prominent and the Shvetsov M-82, which was also used on Lavochkin La-5 fighters. Only a few M-82 variants were produced.

Contents

Design and development

The I-185, designed in early 1940, was based on the I-180, which was itself a development of the I-16, but was virtually a new design. The monocoque fuselage was similarly built of 'shpon', molded birch plywood, and also had an integral fin, but it was considerably longer than that of the I-180. The two-spar, all-metal wing was smaller and thinner than the I-180's wing, nearly as thin as that of the Supermarine Spitfire's wing at 13% at the root and tapered to 8% at the wing tip. [1] The wing had a NACA-230 profile and was skinned in duralumin. Pneumatically powered split flaps and leading edge slats were fitted. The outer wing panels had 3° of dihedral. The fabric-covered control surfaces were framed in duralumin. The protected 540-litre (119 imp gal; 143 US gal) fuel tanks were mounted between the wing center section spars. The I-185 used a conventional undercarriage with a retractable tailwheel. The unproven 1,492 kW (2,000 hp) 18-cylinder, two-row Tumansky M-90 radial engine was carried on welded steel tubes. It was fitted with a ducted spinner to improve cooling with the air expelled through gills as in the I-180 to provide additional thrust. [2] The synchronized armament was mounted in the fuselage, two 7.62 mm (0.300 in) ShKAS machine guns and two 12.7 mm (0.50 in) Berezin UBS machine guns. A 500-kilogram (1,100 lb) bomb could be carried under overload conditions. The first prototype was completed in May 1940, but the only available example of the M-90 did not provide enough power for take-off. The prototype was modified to use another experimental engine, the 895-kilowatt (1,200 hp) Shvetsov M-81 radial, but this was not nearly powerful enough for flight tests. The I-185 (M-81) finally took to the air on January 11, 1941, but it was decided not to waste further development and await a more powerful engine which was fortunate as the M-81 was cancelled in May 1941. [3]

A second prototype was completed at the end of 1940 with a 14-cylinder, 1,268 kW (1,700 hp) Shvetsov M-82A radial engine. The forward fuselage had to be redesigned to accommodate the slimmer engine and the armament was revised to three synchronized 20 mm (0.79 in) ShVAK cannon. The drawings for this engine installation was passed to Lavochkin and Yakovlev where they proved very useful in designing their own fighters using the M-82 engine, notably the Lavochkin La-5. A third prototype was also built that used the larger and heavier Shvetsov M-71 radial engine of 1,492 kW (2,000 hp). The flight tests of both of the latter versions were interrupted by the German invasion in June 1941 and all three prototypes, along with the entire Polikarpov design bureau, were evacuated to Novosibirsk. [4]

Flight testing resumed in early 1942 and the M-71-powered versions, which now included the re-engined first prototype, proved to be faster than the Messerschmitt Bf 109F by 47 km/h (29 mph) at sea level and 20 km/h (12 mph) at 6,000 metres (19,685 ft) with a top speed of 630 km/h (390 mph) at that altitude. [5] It was recommended for immediate production, even before it began combat trials in November 1942. All three aircraft were assigned to the 728th Fighter Aviation Regiment of the 3rd Air Army of the Kalinin Front and were tightly controlled to prevent the loss of the prototypes. For example, all sorties had to be flown over Soviet-controlled territory and required the express permission of the 3rd Air Army staff to fly. [6] Pilots' reports were quite enthusiastic; the 728th's commander, Captain Vasilyaka wrote: "The I-185 outclasses both Soviet and foreign aircraft in level speed. It performs aerobatic maneuvers easily, rapidly and vigorously. The I-185 is the best current fighter from the point of control simplicity, speed, maneuverability (especially in climb), armament and survivability." [7]

Based on the glowing report by the NII VVS (Nauchno-Issledovatel'skiy Institut Voyenno-Vozdushnykh Sil—Air Force Scientific Test Institute) in early 1942 preparations began to put the I-185 (M-71) into production. A 'production standard setter (etalon)' aircraft was built in April 1942 with a redesigned engine cowling. Its gross weight increased by 144 kg (317 lb) over the earlier prototypes, but the reduction in drag from the new cowling was significant and the top speed increased to 650 km/h (400 mph) at 5000 meters. It underwent manufacturer's tests between June and October and was submitted for the State acceptance tests on 18 November. However, flight testing was interrupted by the need to replace the engine between 17 December 1942 and 26 January 1943. The new engine failed the next day and the aircraft crashed on 27 January. Flight tests were ordered to be continued with the original prototypes to validate the range figures, but the first prototype crashed on 5 April, killing the pilot as he attempted a dead-stick landing. [8]

Following a conversation between Yakovlev and Stalin where Yakovlev refuted the performance data, all work to put the I-185 into production was cancelled, even with the M-82 engine, as they were all required for the La-5 fighter. Another reason cited was that the La-5 used the fuselage of the Lavochkin-Gorbunov-Goudkov LaGG-3 which was already in production in three plants and would involve less disruption of the production lines. Another factor may have been that the La-5 required less duralumin to build, something in short supply at the time. [9]

Variants

Polikarpov began preliminary design of two updated versions of the I-185 design in February 1943. The I-187 had a M-71F engine of 1,640 kW (2,200 hp), a bubble canopy, four 20 mm cannons, eight RS-82 rockets and an estimated maximum speed of 710 km/h (441 mph). The I-188 used an improved M-90 engine with 1,552 kW (2,080 hp) and used the same armament as the I-187, although the fuselage was slimmer than that of the I-187 because of the slimmer engine. [10]

Specifications (I-185 (M-71 etalon))

Data from[ citation needed ]

General characteristics

Performance

Armament

See also

Related development

Aircraft of comparable role, configuration, and era

Related Research Articles

<span class="mw-page-title-main">Lavochkin La-5</span>

The Lavochkin La-5 was a Soviet fighter aircraft of World War II. It was a development and refinement of the LaGG-3, replacing the earlier model's inline engine with the much more powerful Shvetsov ASh-82 radial engine. During its time in service, it was one of the Soviet Air Force's most capable types of warplane, able to fight German designs on almost equal footing.

<span class="mw-page-title-main">Mikoyan-Gurevich MiG-1</span> 1940 fighter aircraft model by Mikoyan-Gurevich

The Mikoyan-Gurevich MiG-1 was a Soviet fighter aircraft of World War II that was designed to meet a requirement for a high-altitude fighter issued in 1939. To minimize demand on strategic materials such as aluminum, the aircraft was mostly constructed from steel tubing and wood. Flight testing revealed a number of deficiencies, but it was ordered into production before they could be fixed. Although difficult to handle, one hundred were built before the design was modified into the MiG-3. The aircraft was issued to fighter regiments of the Soviet Air Forces (VVS) in 1941, but most were apparently destroyed during the opening days of Operation Barbarossa, the German invasion of the Soviet Union in June 1941.

<span class="mw-page-title-main">Yakovlev Yak-3</span> Fighter aircraft

The Yakovlev Yak-3 was a single-engine, single-seat World War II Soviet fighter. Robust and easy to maintain, it was much liked by both pilots and ground crew. One of the smallest and lightest combat fighters fielded by any combatant during the war, its high power-to-weight ratio gave it excellent performance and it proved to be a formidable dogfighter.

<span class="mw-page-title-main">Lavochkin La-9</span> Soviet fighter aircraft in service 1946-1959

The Lavochkin La-9 was a Soviet fighter aircraft produced shortly after World War II. It was one of the last piston engined fighters to be produced before the widespread adoption of the jet engine.

<span class="mw-page-title-main">Shvetsov ASh-82</span> Soviet aircraft engine

The Shvetsov ASh-82 (M-82) is a Soviet 14-cylinder, two-row, air-cooled radial aircraft engine developed from the Shvetsov M-62. The M-62 was the result of development of the M-25, which was a licensed version of the Wright R-1820 Cyclone.

<span class="mw-page-title-main">Polikarpov I-180</span>

The Polikarpov I-180 was a 1938 Soviet fighter prototype. It was the last attempt to extract performance from the basic Polikarpov I-16 design. The development cycle was plagued with problems, especially with the death of the star Soviet test pilot Valery Chkalov in one of the prototypes.

<span class="mw-page-title-main">Polikarpov ITP</span> Soviet fighter prototype

The Polikarpov ITP was a Soviet fighter prototype designed during World War II. Development was prolonged by the evacuation of the design bureau forced by the German advance on Moscow in the fall of 1941. By the time the second prototype was finished the Soviets had fighters with equivalent or better performance already in production and the program was cancelled.

The Lavochkin La-126 was a World War II Soviet prototype piston-engined fighter aircraft.

<span class="mw-page-title-main">Polikarpov I-153</span>

The Polikarpov I-153 Chaika is a late 1930s Soviet sesquiplane fighter. Developed from the I-15 with a retractable undercarriage, the I-153 fought in the Soviet-Japanese combats in Mongolia and was one of the major Soviet fighter types in the early years of the Second World War. Three I-153s are still in flying condition. The I-153 is powered by the Shvetsov M-62 radial engine.

<span class="mw-page-title-main">Lavochkin-Gorbunov-Gudkov LaGG-3</span> Type of aircraft

The Lavochkin-Gorbunov-Gudkov LaGG-3 was a Soviet fighter aircraft of World War II. It was a refinement of the earlier LaGG-1 and was one of the most modern aircraft available to the Soviet Air Force at the time of Germany's invasion in 1941. Compared to its opponents the LaGG-3 was underpowered and, despite its wooden construction, overweight. It was unpopular with Soviet pilots, but despite this, at one point in the war, on average 12 LaGG-3s were being completed daily and 6,528 had been built in total when production switched to the Yak-3 in 1944. The LaGG-3 was steadily improved, forming the basis for the more successful La-5 and La-7.

<span class="mw-page-title-main">Polikarpov I-3</span> Soviet Polikarpov biplane fighter

The Polikarpov I-3 was a Soviet fighter designed during the late 1920s. It entered service in 1929, but was retired in 1935 with the advent of fighters with higher performance.

<span class="mw-page-title-main">Polikarpov I-6</span> Soviet Polikarpov biplane fighter

The Polikarpov I-6 was a Soviet biplane fighter prototype of the late 1920s. It was designed with traditional wooden construction in comparison with the wood and steel tube construction Polikarpov I-5. Its development took longer than planned and the lead designer, Nikolai Polikarpov, was arrested for industrial sabotage, which only further delayed the project. Only two prototypes were built, as the I-5 was selected for production.

The Yakovlev Yak-5 was an experimental trainer aircraft designed by Yakovlev OKB in the Soviet Union, and first flown in 1944.

<span class="mw-page-title-main">Borovkov-Florov I-207</span> Type of aircraft

The Borovkov-Florov I-207 was a fighter aircraft designed and built in the USSR from 1936.

The Shvetsov M-71 was a Soviet radial engine built in small numbers during World War II. It was derived from the Shvetsov M-25, which was a license-built copy of the American Wright R-1820-F3 Cyclone engine.

<span class="mw-page-title-main">Polikarpov NB</span> Type of aircraft

The Polikarpov NB was a Soviet twin-engined bomber designed during World War II. Only a single prototype had been built before the program was terminated upon the death of Nikolai Nikolaevich Polikarpov, the head of the aircraft's design bureau, in 1944.

<span class="mw-page-title-main">Tupolev I-14</span> Type of aircraft

The Tupolev I-14 was a Soviet fighter aircraft of the 1930s. It was a single-engined, single-seat monoplane with retractable undercarriage, designed to carry heavy armament, and as such was one of the most advanced fighters of its time. It was ordered into production, but this was cancelled after only a small number had been built, the competing Polikarpov I-16 being preferred.

The Yakovlev AIR-6 was a Soviet light utility aircraft of the 1930s. It was a single-engined high-wing monoplane designed by Alexander Sergeyevich Yakovlev, with 128 being built.

<span class="mw-page-title-main">Yakovlev AIR-7</span> Type of aircraft

The Yakovlev AIR-7 was a prototype Soviet high performance light aircraft of the 1930s. It was a two-seat single-engined monoplane, which demonstrated excellent performance during testing. After the prototype almost crashed as a result of flutter, its designer, Alexander Sergeyevich Yakovlev suffered temporary disgrace and no production followed.

The Yakovlev Ya-21,, was a single-seat high-speed sport aircraft / fighter-trainer designed and built in the Soviet Union in the late 1930s.

References

Notes

  1. Gordon and Dexter, pp. 94–95
  2. Gunston, p. 308
  3. Gordon and Dexter, p. 95
  4. Gordon and Dexter, pp. 95–96
  5. Gordon and Dexter, pp. 96, 100
  6. Gordon and Dexter, p. 100
  7. Gordon, p. 275
  8. Gordon, pp. 275–76
  9. Gordon and Dexter, p. 101
  10. Gordon, p. 277
  11. Lednicer, David. "The Incomplete Guide to Airfoil Usage". m-selig.ae.illinois.edu. Retrieved 16 April 2019.

Bibliography