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The AM-42 started out in life as the AM-34, designed in Italy, and morphed into the AM-35, then the AM-38 and, finally, the AM-42. It had some Soviet input in that time, naturally, but was a larger-displacement engine than the MNerlin or the Allison ... alrgely due to les sophisticated fuel used in development and operation. It had the very unique characteristic of having a longer stroke on one side than the other due to articulated connecting rods on one side!
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Here's some typical engines used in a variety of warplanes, certainly not the largest engines of the war, but does give an idea of how big those engines were on average:
Rolls-Royce Merlin 61: 1,647 CID (27L)
Allison V-1710-F30R: 1,710 CID (28.02L)
Daimler-Benz DB601A: 2,070.5 CID (33.93L)
Junkers Jumo 213E: 2,135.2 CID (35L)
Klimov VK-107A: 2,140 CID (35.08L)
Mikulin AM-35A: 2,847 CID (46.66L)
I was thinking of the DB 603A at 44.52 L (2,716.9 in3)
Like I said, those were average sizes and look at how they performed in the aircraft they were installed in.
There were much larger engines that were in use (this does not include prototypes or dead end projects):
Rolls-Royce Vulture V: 2,592 CID (42.47L)
Junkers Jumo 222A: 2,830 CID (46.5L)
Mikulin AM-42: 2,847 CID (46.66L)
Allison V-3420-A18R: 3,420 CID (56L)
AA Fueler Dragster engines run about 10 - 12 seconds max. About halfway down the dragstrip the spark plugs are burned away and it is dieseling. They wouldn't last as long as a takeoff run for Piper Cherokee 180. I have never considered them to be anything but dragster engines and won't. But I DO love to watch them run. The WinterNationals will be soon at Pomona Raceway and I'll BE there. In addition to the dragsters, they will have a cacklefest, too. Don Garlits, Don Prudhome, and a lot of others will be there with cars from the past that start and run. Maybe they'll be allowed to do some slow runs ... if they stay under 200 mph or so.
If someone asked for a list of engines, then go for it.
I still say NOBODY could build a large-displacement, 1500 - 2500 HP, liquid-cooled piston aero engine today without a LOT of development. They have just lost the formula and would need to rediscover it. What is needed is GREAT power at LOW rpm ... depending on propeller diameter. Can't design one without the other unless you are resigned to a PSRU, and most WWII engines WERE geared except for some smaller radials that had both geared and direct drive units produced. They were NOT the power champs.
An engine is nothing more than a big air pump and direct drive engines will always pump less air than a geared unit of the same displacement.
AM-34 was designed in Italy, while the AM-42 have had only 'some Soviet input'? You are unbelievable, Greg.
BTW, the standard Soviet fuel was 95 oct, suspiciously close to the German of 96 oct C3 fuel, and not that far away from Allied 100 oct.
It seems to me that radials were never really fully developed.
Two of the most remarkable fighters of WW2 was the Fw 190A and the Vought Corsair.
The Corsair was the first American aircraft to exceed 400mph and I believe that was a result of the USN spec PW R2800 which had a two stage multispeed (independent drive) supercharger with intercooler that could maintain power into the thin air of high altitude where parasitic or form drag was less.
Also remarkable is the Fw 190A which managed this feat with only a single stage two speed supercharger likely as a result of the low drag installation made possible by the forced fan cooling which reduced engine cooling inlet area and eliminated the area subtended by the oil cooler in the propeller blade area.
Had the two techniques been combined I believe we would have radial engines beating water cooled engines.
The only 400+ mph aircraft in service till 1944 with single stage superchargers I believe was the Typhoon and Fw 190, which had almost exactly the same speed.
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The Continetal AV-1790 engine needs to be mentioned. An air cooled V-12 5.75 inch (146mm) bore x 5.75 inch (146mm) stroke, it started in the 1950s as a 600 hp gasoline (spark ignition) engine. Later versions were compression ignition (diesel), with the latest offering 1200 HP @ 2400 rpm. It continues to be availble as an engine for tanks and other heavy military vehicles.
I am sure that if the governor were recalibrated to allow operation at 3000 or even 3200 rpm, that it could produce 1500 HP or more, for 5 minutes. That is starting to get into Merlin / DB 601 / AM-37 kind of power.
Downside is, at least according to the internet, it is a real porker, weighing 4000 pounds or more AS A TANK ENGINE. Before we immediately discount this engine, we need to consider the differences between a tank engine and an aircraft engine. Since a tank has to be able to pull full power while moving oh so slowly across the desert, the 4000 pound weight includes high capacity fans for cooling which an aircraft engine lacks. The quoted weight includes an oil cooler, also sized for desert operation, while the oil cooler is usually not included in the quoted weight of an aircraft engine. There is also likely a lot of extra metal in a tank engine (compared to an aero engine) to allow it to run after the concussion of a shell hit against the armour. Plus what sort of expectation for time between overhauls on a tank engine compared to a aircraft engine.
That is all I think I know.
it had a variable compression ration, achieved by hydraulically varying the length of the connecting rods.
Wonder if this is why diesel automobiles are so popular in Europe?
Ideal if the public and the military can share fuel.
Might be very indirect. Like if there are policies on taxes on diesel fuel vs gasoline or something.
It was big back in the 50s when NATO was gung-ho on Multi-fuel engines. Fill the fuel tanks with what ever you could find, flip a few switches or twist a dial on the control panel and away you go
Turns out it didn't work all that well, Some engines lost 10-20% in power running on gasoline compared to diesel fuel and the increased cost of the engines, the break downs, and maintenance/overhaul pretty well killed it.
It was reason the US started down the Turbine engine path though, Early ground use turbines were touted as being able to run on anything from home heating oil to peanut oil. Eco-Friendly tanks?