Yakovlev M-501 - The BIGGEST Piston Radial Ever Designed

what's the first thing that comes to mind when i say cold war russian engineering sputnik yuri gagarin and the vostok one how about that abandoned knockoff space shuttle still sitting in a hangar and baikonur or how about this gargantuan 8 759 cubic inch 42 cylinder radial engine never heard of it what if i told you they then upgraded it to 56 cylinders and gave it a two-stage turbo supercharger rookie numbers right they definitely need to pump those numbers up and they did they bolted two of them together into a 112 cylinder 22 361 cubic inch hulk making 10 500 horsepower now this engine wasn't entirely inefficient and actually had pretty good specific power and power to weight ratios but it does seem like the russian engineers when faced with a problem have a tendency to just keep increasing the size this is the story of the goliath yakovlev m501 radial engine the most monstrous colossal production aircraft radial engine ever created when hostilities ended after the war the russian experimental design bureau was tasked with rebuilding junkers yumo to four diesel aircraft engines however a man named vladimir m yakovlev had something else in mind and finally convinced his superiors to let him start development on what he dubbed the m501 in 1948 the development of the yonkers yumo 224 finally stopped and the design and development of the m501 properly began the design was a large water-cooled four-stroke diesel aircraft engine with 42 total cylinders oriented in seven banks of six cylinders each the crankshaft assembly consisted of seven sections bolted together when fully assembled it had six throws supported by seven roller type manned bearings each six cylinder bank was connected to the crankcase by studs inside each cylinder were four total poppet valves two for intake and two for exhaust driving these valves were cams driven through bevel gears by a vertical shaft at the rear of each cylinder bank in each row of cylinders the pistons were connected to the crank via a master rod assembly and six articulating rods exhaust exited the banks on the left side of each bank and routed directly into a manifold on the upper part of the v after flowing through the turbo supercharger the remaining exhaust pressure provided an additional 551 pounds of thrust after this turbo supercharging high pressure intake air was routed through a mechanical supercharger between the turbo and the engine itself resulting in a two-stage forced abduction system the cylinders of the m501 used a 6.3 inch bore and a 6.69 inch stroke total displacement was 8 759 cubic inches or 143.6 liters total power output was 4750 horsepower without the turbo supercharger and 6205 with it obviously the m501 was not a light engine without its turbo it weighed a crushing 6504 pounds with it it tipped the scales at 7459. in 1952 further testing clocked the m501 at over 6000 horsepower during tests but the program was cancelled in 53 due to jet and turbine engines proving to be a better solution for powering large bomber aircraft before the program's cancellation the m501 was intended to power the tupelo 487 the iliation il-26 and the tupolev 489 but none of these aircraft were ever produced instead of scrapping the project altogether though the m501 was instead converted into the m501m a marine variant using a steel crankcase rather than its original aluminum one the engine featured a power takeoff reversing clutch and water jacketed exhaust manifolds early versions of the marine engine suffered from several teething issues but these were eventually ironed out in the 1960s when the engine became more reliable the primary factory producing the engine number 174 was renamed fedsta meaning star after the engine's star-shaped layout zvezda would continue to produce the m501 until refining it into what became the m503 the m503 used the same basic configuration as the m501 but used a compounded turbo supercharger with the compressor wheel connected to the crankshaft via three fluid couplings in this case the compressor wheel shared the same shaft as the exhaust turbine wheel this design was chosen because at low rpm the engine didn't have enough energy to power the exhaust turbine so instead it depended on the crank powered compressor at high rpm the turbine powered the compressor creating around 16 pounds of boost excess power from the turbine was fed back into the engine via couplings connecting the compressor to the crankshaft compression ratios of the m503 were 13 to 1 and max output was rated at 3943hp at 2200 rpm the colossus of an engine measured 12 feet long and was 5.1 feet in diameter typical service life was between 1 500 to 3000 hours [Music] m503s were most often used in osa class fast attack missile boats because one obviously wasn't enough three were installed you know it makes me wonder what it would cost to fill your 168 cylinder missile boat with gas on another note a competitive tractor pulling team has adapted a heavily modified m503 svetsta into their tractor's design the engine has been converted to spark ignition and uses methanol fuel each custom cylinder head features three spark plugs and a modified supercharger that deletes the turbine according to the team the engine produced more than 10 000 horsepower at 2500 rpm weighing about 7 055 pounds the most powerful production variant of this vesta was the m517 with a rated output of 6370 horsepower but by far the most insane variant was the m507 the m507 coupled two 56 cylinder m503s together from front to front with a common gearbox in this configuration each engine could run independently of one another but the total 112 cylinder package displays 22 361 cubic inches and the maximum output was rated at 10 453 horsepower at 2200 rpm unsurprisingly this beast was not a compact piece of machinery measuring over 22 feet long and weighing nearly 40 thousand pounds about as much as a garbage truck today despite gas turbines taking over much of the diesel marine engine's intended market the zvezda company continues to produce repair and develop its line of m501 engines the m501 was perhaps a naive creation not too dissimilar to frankenstein's monster a mountain of an engine upsized and constructed from the best of discarded bits of kit left lying around after the war while other engineers were busy tinkering with their new jets yakovlev was if you'll allow me to stretch the metaphor a bit raising the dead while it was never used for its intended purpose it's still an impressive piece of engineering and even more impressively it's still being used today ensuring for the time being that the world of ludicrously oversized radials never dies and you know a part of me hopes it never does [Music] hey guys i just wanted to take a second to acknowledge how blown away we are by the amount of you who flooded into the channel and made us feel welcome as we launched this series we have a lot more planned and we're glad you're liking it that being said if you have a piece of aviation history you'd like to see us cover feel free to leave a comment below and we'll investigate right now we're feeling pretty lucky to be here thanks to you so thanks guys we uh we hope you enjoyed this video and as always thanks for tuning in to flight dojo see you next time [Music]

Channel: Flight Dojo

Views: 697,743

Keywords: aviation, engine history, big engine, cold war soviet, cold war, engine design, soviet engineering, large aircraft engine

Id: AG8iloB3ptE

Length: 8min 5sec (485 seconds)

Published: Wed May 25 2022