Shvetsov M-82 / ASh-82 / ASh-2TK / ASh-2K (ASh-4K)
The Shvetsov ASh-82 (M-82) is a 14-cylinder, two-row, air-cooled radial aircraft engine developed from the Shvetsov M-62 and first run in 1940. The M-62 was the result of development of the M-25, which was a licensed version of the Wright R-1820 Cyclone.
Arkadiy Shvetsov developed the Wright Cyclone design, reducing the stroke, dimensions and weight. This allowed the engine to be used in light aircraft, where a Twin Cyclone could not be installed. It entered production in 1940 with Shvetsov & Evich, OKB-19 in Perm, and saw service in a number of Soviet aircraft. It powered the Tupolev Tu-2 and Pe-8 bombers and the inline engine-powered LaGG-3 was adapted for the ASh-82, additionally the famous Lavochkin La-5, Lavochkin La-7 fighters, and the Ilyushin Il-14 airliner were created around the engine. Over 70,000 ASh-82s were built (57.898 of Ash-82, 82F & 82FN in wartime).
ASh-82-112 (M-82-112) - Improved M-82-111 with longer Time between overhaul (TBO) and better reliability. Redesigned carburettors, oil pumps, gear, turbocharger and reinforced pushrods. This engine worked better in the harsh Russian winter.
ASh-82F (M-82F) - Identical to ASh-82 except for longer Time between overhaul and improved cooling and lubrication which allowed unlimited operation at takeoff power.
ASh-82FN (M-82FN) - ASh-82F with gasoline direct injection, power output increased to 1,230 kW (1,650 hp) for takeoff with only a 30 kg (65 lb) increase in engine weight, used by Pe-8 long-range bombers and Lavochkin La-7 fighters.
ASh-82FNU (M-82FNU) - Improved M-82FN with more boost pressure and RPM, power output increased to 1,380 kW (1,850 hp). After all the improvements, the ASh-82FN and ASh-82FNU were two of the most sturdy radial engines of the war.
ASh-21 (M-21) - Single-row 7-cylinder version of ASh-82 for Yakovlev Yak-11 trainer, entered production in 1946.
ASh-82T (M-82T) - New version of the Ash-82FNU developed in the early fifties for civilian aircraft. Previous version twin superchargers were replaced with a large single-speed compressor attached to an after-cooler (the critical altitude was 2,000 m, 6,561 ft). Optionally, the engine was provided with a two-speed supercharger (with a critical altitude of 4,000 m, 13,123 ft, the robustness of the engine allowed to take off in second speed). New alloys were used and some components were upgraded, thus reducing maintenance operations. Special care was put into reducing the engine noise level and an optional exhaust double silencer was available. The engine had a new fuel injection system and improved specific fuel consumption (a 16% reduction at cruise speed compared to 82FNU). A four-blade high efficiency propeller, the Typ AB-50m, was developed for the 82T version. This radial engine had an excellent reputation for its reliability and simple maintenance; there are still aircraft in service with this engine thanks to the inexpensive spare parts and the possibility to use automotive gasoline. The power was 1,900 hp (1,417 kW) at 2,600 RPM for takeoff, with 95 or 100 octane Avgas. Maximum continuous power was 1,630 hp (1,215 kW). Lower octane fuel, 90 octane Avgas or equivalent automotive gas, was allowed with minor modifications and turbocharger Manifold Pressure restrictions that limited the power to 1,700 hp (1,268 kW).
ASh-82V (M-82V) - Helicopter version of the ASh-82T developed in 1952, with axial-flow fan mounted in the fuselage's front. The engine was connected to a R-5 two-stage planetary primary gearbox with the help of a shaft (which was between the pilots seats). This engine was used in the Mi-4 and Yak-24 helicopters
ASh-2TK and ASh-2K (ASh-4K) – Four-row versions of the ASh-82, developed in the late '40s. The Shvetsov design bureau took into consideration all available information about the Pratt & Whitney R-4360 and developed an engine with less maintenance operations, longer time between overhaul, direct fuel injection and a simpler supercharging system. The ASh-2TK had a two-stage two-speed supercharging system with intercooler (similar to the ASh-73) that compromised the engine's long TBO. Finally the ASh-2TK was discarded and a new version was developed, the ASh-4K, with an experimental variable-speed turbocharger and after-cooler, which allowed a cruising altitude of 11,000 m (36,089 ft). The engine had 82.4 litres (5,030 cu in) and 4,000 HP (2,985 kW) at 2,600 RPM (dry). The Ash-2K (ASh-4K) version had 4,700 HP (3.507 kW) wet, with a water-methanol system. For political reasons, these engines were prematurely installed in Tupolev Tu-4LL testbeds at the end of 1950, when the prototypes' initial tests had barely begun. The engines had various teething and overheating problems, and required a long testing period. Most of the flaws were fixed in the mid-fifties, but the production was cancelled: in those days, the priority for the Soviet Air Force were the turboprop and jet engines.
Dongan HS-7 A Chinese license built copy of the ASh-82V, and the chosen engine for powering modern 21st century reproductions of the Focke-Wulf Fw 190A built in Germany.
Dongan HS-8 A modified version of the Dongan HS-7 which "combined the main body and supercharger of the HS-7 with the reduction gear and propeller drive of the Shvetsov ASh-82T". Built by Dongan Engine Manufacturing Company (aka Harbin Engine Factory)
M-82FN with direct fuel injection:
M-82T with two speed supercharger: