9 Of The Largest Piston Aircraft Engines Ever 

*INSANE!*

What is that in freedom units? 8,000 cheeseburgers per toe?

@@SoI_Badguy I thought it was roughly 6,000 hands - horses

radials often redline between 2000 and 3000 rpm so about 1.8 - 2 times the horsepower to get to feet pints.

Just wait until the Tesla roadster

Don't forget diesels now too!

You left out the part where all of these WWII era radial engines were designed to work with high octane Avgas, which contained tetraethyl lead. As TEL got phased out (because environmental lead slowly poisons people and makes children retarded), getting supplies of this high octane Avgas has become a major limiting factor in continuing to economically operate these old engines.

Think, it was less than 50 years before that, that horse and buggy was more common than car. We went from clopping around behind beasts of burden to flying with birds in less than one mans lifetime. Amazing.

Well "reliable" only if you maintain it. The tolerances were huge and they all leaked oil. Tons of oil.

@@carlosandleon they didn’t maintain them during the war they did the bare minimum to get them back in the air obviously after the war maintenance was a much bigger thing. Every engine from this time period leaked oil it doesn’t matter if it was a lawnmower or an aircraft engine we had only been making engine for a handful of decades we didn’t have all the good gasket materials and sealers that we do now and I’m sure they didn’t know that one gasket material will seal better with a rougher machined surface and another gasket with seal better if it were smoother and we for sure didn’t have good seals I mean just look 50 years ago with cars where they had rope rear main seals it was just normal for every car to leak oil. The tolerances of engine manufacturing back then was also bad all the way around and even worse was balancing engines you can find videos from back then where a person is weighing pistons on a scale and before the needle on the scale stops moving they pull the piston off to put another on it lol. There are still surpluses of new old stock engine parts from ww2 for these old engines that still get used. Nowadays it’s normal for a little 4cyl engine in a car to rev past 7,000 rpm smoothly because they are balanced so well and they take thin 0w20 oil because the tolerances are much tighter. I use to work for a Saturn dealership as a mechanic and they used a Saab v6 engine in a few cars and the tolerances were so perfect they didn’t have a stock size main bearing every engine would usually have multiple different size bearings because they manufactured them to much tighter clearances and because they did such a great job machining the bottom ends they would never come in with spun bearings I think the entire time I worked there we did a crank on 2 engines because someone cracked the oil filter housing and leaked all the oil out. Engines have came a very long ways! My grandfather worked on the b-29’s in the Korean War I think they had 18 cylinder wright engines, he flew all over the world in them on missions he said the biggest problems were with the magnetos and then cylinders would crack some times but he said the cylinders were more of a problem when the were doing training in northern Canada because of the super cold weather. Either way it’s amazing some of these old air frames are 80 years old and still in use!

Impressive, but I can't get them to rhyme.

You really believe u can shoot away a complete cylinder and fly for hours? Your BS alarm should go off immediately. Such accounts are fake.

DB603 A as installed in the Me410 is supercharged, but you are absolutely right it sounds sweet.

Damn straight 👍

I was wondering how that ended up in this video about recips

The Il-2 shown flying is powered by an Allison V-1710, as there are no Airworthy AM-35 oe 38 Engines.

Epic Fail... ;-)

Definitely turboprop. Can't fit a big radial like he was talking about in the small of a cowl.

The IL18 shown is a popular aircraft in many Eastern countries. The 1946 plane was an abandoned project.

The Il18 in the video is an Air Koryo plane, I've seen the original video from a group of aviation enthusiasts having trips in several planes.

Sleeve valve monster. It out breathed any poppet valved 'plant but had a lot of extra machinery all the way around that radial.

Much appreciated!

Incidentally, it is not uncommon for multi-engined aircraft to have their engines spin in opposite directions specifically so that this torque effect will be mostly self-cancelling.

You better get a move on then. I'm still waiting to to see a flying Typhoon in my lifetime

cannot find footage of that bug doing anything but getting started.

The Hawker Fury with Napier Sabre is shown just after the Corsair at 3:57. That had 37 litres from two crankshafts and 24 cylinders. In late 1944 they were doing 2,400bhp but eventually made 3,500 bhp. Test bed engines reached 5,500bhp.

@@davidelliott5843 Sorry mate...not a Napier. That is the Bristol Centaurus. There are no Sabres running at the moment, until the UK Hawker Typhoon resto comes to life in 4 or 5 years.

Agree! Waiting for the Typhoon!

@@@johnmclean6498 - Sorry mate... not a Centaurus. The engine installed in the Fury at 3:57 is an overhead valve design (you can see the rocker covers). The Centaurus is a sleeve valve design.

Which is why they dumped it for the Bristol Centarus.

Each engine had it's own crew..

Well, so far, no mention of the biggest of them all. The Lycoming XR 7755. That's 7755 cubic inches, 36 cylinders, 5000 horsepower. Built around 1948. 2 were built and there is a photo of it and its development crew on Wikipedia. It never flew, but was successfully run up on the dyno, eventually producing 5000 hp. With the jets coming on the scene, its market disappeared.

Radial engines usually smoke on startup because bottom cylinders collect some engine oil if it is not running for some period of time.

YES! Something somehow soothing about the sound of a big radial. The big V12's too!... The jets are awesome yes, all light and small and powerful and reliable... But their shrill, screechy sound will never match the charismatic rumble, the melodic charms of the big old piston engines!

Good luck tryna make it quiet

Good luck keeping it together

You'll have to put a car around the engine.

@@bradcogan8588 Yes

Nice idea bro

Turboprops are jet engines blowing on a wind turbine. So are turbofans. The difference is what the turbine drives (an unducted prop or a ducted prop)

I can confirm the Ash-73 comment. 1. Totally wrong sound for a piston engine on the first and third plane. 2. Totally wrong exhaust plumes on second plane. (No gasoline aircraft piston engine smokes black) 3. Totally wrong cowling shape for a piston engine (no cooling flaps on all three planes) About the R-4360 cant say for sure, but the 'Fifi' was a B29 which were indeed powered only with R-3350s.

The B-50 used R-4360's, and looks alot like a B-29

R4360s were used on many different airplanes. Already mentioned is B50, but also C & KC97, B36, C119, C124, and Boeing's civilian version of the C97.

Basically the B-50 is a upgraded version of the B-29. But you can easily spot the main differences: - Chin coolers under the engines nacelles. - And a much taller tail fin. The B-29 was planned with the R-4360 but the engine wasn't ready fast enough. So it had to be build with R-3350s, which were a fire hazard.

Not change them. Remove them. Clean them. Inspect them. Gap them. Test them. Reinstall them. Every 50 hours or 25 hours.

The B-36 Peacemaker had 6 of these engines and since the Peacemaker was too big to fit in a hangar the maintenance crews had to service the engines outside... 2 spark plugs per cylinder, 28 cylinders per engine and 6 engines per plane.

Not to mention the use of that cumbersome, hard to read slide rule.

Try the engines of a Super Constellation, not just turbo chargers, superchargers, buckets of sparkplugs, mass quantities of oil, but a power recover turbine coupled via viscous coupling to the crank.

I was a Reciprocating Aircraft Engine mech when I was in the Air force. I worked on R-2000's, R4360's and R1300's. The 4360 was the sweetest sounding engine of them all, but it was much harder to work on than the 2000 or the 1300.

Agreed. Once initial reliability problems were overcome the Sabre was a potent engine, most famously used in the Hawker Typhoon and later Tempest. It is interesting to note that Napier ran into problems with the Sabre and the great Roy Fedden from rival manufacturer Bristol was co-opted into ironing out the problems.

As far as i am aware the engine never made anything close to 5500hp. The last production version (the Mk VII) was rated at 3050hp. There were reports that the Mark VIII made around 4000hp with a completely redesigned induction system but I have not seen any documentation to back the claim. I suspect the 5500hp number is the structural design capacity of the engine before it breaks, not its actual output. This number would be considerably more than its original design as the engine had two major redesigns of its internal structure (including discarding the crankshaft counterweights!) through its life, The engine was almost single handedly designed by Major Frank Halford who was unfairly blamed for many of the problems with the engine, the original hand made prototypes worked very well. Unfortunately, Napier could not rely on its highly skilled craftsmen to build the engines in production and the design really wasn't well suited to the unskilled workforce engaged by Napier in war time. The tolerances required in the sleeve valves was far tighter than RR employed in its engines. It has been said that Napier's original production facilities resembled something you would find described in a Charles Dickens novel. I think that Napier, as a company, just wasn't well suited to large scale production. Things improved dramatically after English Electric acquired the company. There are some very interesting stories about the engine including the redirection of some precision centreless grinders from Pratt&Whitney to Napier. I do not think P&W was very happy about it. When all the production problems were occurring, Frank Halford had already closed his design shop and returned to working for de Havilland exclusively. He designed all three of their gas turbines, the H1 (the Goblin), The H2 (used in the Comet but only indirectly related to the sad history of that aircraft), and the H3. Anyhow the Napier Nomad was much more complex than the Sabre, it being a compound engine, half gas turbine, half 2 stroke diesel with many unconventional design features. Features such as the load sharing variable ratio Briers coupling that transferred the excess power from the 3 stagepower turbine (that is, power turbine produced several hundred hp more power required by the 12 stage axial compressor to function as a supercharger) to the 2 stroke diesel crankshaft. All the power was transferred by a very thin film of oil in shear!!. The whole engine was far too complex to be used in the field. The US Airforce looked at the engine design in ( I think) the 90s when assessing aircraft engine design (Again I think it was helicopter design) but baulked at the complexity. Even the two stroke diesel was unconventional, its fully ported loop scavenged combustion chamber did not have enough cylinder compression to ignite the fuel charge (when running at power the supercharger provided enough extra compression to support ignition) so Napier designed a primitive spark ignition system to start the engine. There were many other unusual features including the opposing conrods running on the same crankshaft journal with NO offset, there were no caps on the conrods just thin retaining rings that stopped the conrods from falling off the journal when the engine was starting or not running. Even the big ends themselves were unconventional, too hard to explain and I doubt most people would believe it. Composite pistons made of alloy with a pressurised oil cooled iron crown, the list is just too long. So why design it? The Nomad's main claim to fame was that it was the most fuel efficient aircraft engine ever built, i do not know whether it still holds that title. You can find some contemporary articles on this engine and other engines (RR Griffons) in the Flight magazine which is archived on WWW. Sorry, but i can't remember in which editions they were described. Worth looking up was the RR Crecy, a very unusual engine in its own right. I have read THE book on the engine and it is well worth the read. I haven't read the other two books that include the Crecy. One is on all the 2 stroke aircraft engines so it includes the Nomad as well, the other book is on RR engines only.

@AMCKenA I like Setright's books but I don't necessarily believe everything he wrote in them. I suspect some of what he wrote was apocryphal. The 3050hp number I mention comes from Napier advertisements in Flight magazine post WWII. They never advertise it at any higher power. The 3750hp is believable for the MarkVIII and although I can believe the 175 hours but I have difficulty with it being continuous and at that power level. 4200rpm is about 400 rpm higher than the max for the engine in production and although possible it is also hard to accept. I would think Conrod velocity would be getting up in the danger zone although I have not calculated it. There is also the issue about what fuel they were using with charge air pressures of 45psi. The Nomad used higher pressures but it was a diesel and I think one experimental (well, more experimental) RR Crecy used pressures at this level but it was a direct injection, stratified charge petrol engine. BMEP is usually calculated not measured, so if any of the figures (rpm or hp)are out BMEP will be equally out. Don't get me wrong, the Sabre is one of my all time favourite engines. I am fascinated by its design including the elegant way used to stop lash on the propellor reduction gear set which also serves to couple the two banks of the engine. Its designer is, in my opinion, grossly overlooked. But despite all this, I don't overlook it failings, not the least of which was amount of money and effort that was diverted to its production. The same can be said of the RR Crecy and the whole range of sleeve valve engines built by Bristol. The RR Crecy, Exe, and Pennine were all sleeve valves engines (Crecy was two stroke and had somewhat different sleeve valve arrangement). In the book i have on the Crecy (currently on loan and not available), it is mentioned that Bristol spent more money ( maybe twice as much) and effort on determining the best material for the sleeve valves than was spent by Power Jets on the entire effort to develop the gas turbine! I don't know whether this is true, it was said by a RR engineer, I think. The British were not alone, both the Americans and especially the Germans diverted massive resources and people to complex and totally unnecessary projects. The Germans, apart from the V weapons, the advanced tanks were unnecessary (the Russian tanks were primitive but they could build a lot of them, the Russians weren't stupid), Junkers completely disabled the German Heavy Bomber Programme with their Jumo 222 and also spent a considerable amount of resources on the extraordinary Jumo 223, similar to the Deltic except having 4 banks of cylinders arranged in a rhomboid (technically superior to the deltic as all the crankshafts rotate in the same direction), and the even bigger Jumo 224. Then there was the RR Vulture and Peregrine. Daimler Benz on the DB606 and other developments. Heinkel also ran a number of high end projects that fail the sensible test. Anyhow back to the Sabre. I assume that people at the Napier Power Heritage Trust would have a more informed view of what was the max power of the Sabre. i must drop them a message and see what documentation is available. During a quick look at their website, I can only see them mentioning 3000hp

@AMCKenA By the end of the war it was clear that the competition was all about fuel and air charge. The only other part of the competition was keeping the engines in one piece. RR's greatest advantage was the design of its supercharger. Their other main advantage was their continuous development process. I think it may have been Setright who described the Merlin as the triumph of development over design. The Griffin was a far better designed engine. Obviously the higher RPM possible with the smaller stroke of the Sabre was a big advantage but it was offset (to a degree) by the larger number of moving parts and thus inherently lower reliability, not to mention weight. At this point consider this; the power produced by the engine is determined by the mass of air that can be delivered by the supercharger/ turbocharger/ turbo-supercharger. Even if the rest of the engine was up to the task the Sabre's supercharger wasn't. This is exacerbated by the lack of charge air cooling (often erroneously called intercooling) As is well reported, the Napier powered fighter planes really weren't good at high altitudes, a consequence of the design of the induction system. Napier was apparently redesigning the supercharger when English Electric took control of the company. Rightly, English Electric decided it needed to focus on correcting the reliability issues of the engine. After the war Napier redesigned the induction system for the Mark VIII. In the end, it was the better fuels available to the allies that provided the 'edge'. In this, there is a difference between bomber and fighters. After the failure of the RR Vulture X24 in the Manchester bomber and its subsequent replacement by 4 Merlins which turned the Manchester into the Lancaster, it became clear that 4 engines were indeed better than 2. This is not so clear in fighters, A single high power engine was the traditional solution for fighters. Later in the war, this traditional view was tested by a number of 2 engined fighters designed by the Britishs, Americans, Germans and perhaps the Russians. There are several to chose from but my favourite is the DH Hornet. It doesn't hurt that it looks like an over engined scaled down Mosquito, itself inspired by the beautiful DH88 Comet. At one time DH considered using the Sabre but the reliability/availability of the engine steered them back to the Merlin. Although Ricardo maintained that the sleeve valve allowed a higher compression ratio by one (that is from say 6 to 7) on the same fuel, I do not know whether this was proven and if so whether it was the case later in war. At 45psi (3 atmospheres!) the temperature out of a practical induction system is going to require a very high grade (octane) of fuel to avoid detonation and the consequent failure of the engine. I am not sure that the maximum grade available at the time (100/150) would be sufficient for such an induction pressure and temperature, even taking into account ADI (anti detonation injection i.e. water/alcohol injection). I am having difficulty finding information on the boost pressures used in test bed Merlin/Griffins. It appears that 25 PSI was the highest used in production engines. Interestingly, the 'turbo wars' in 80's F1 racing faced the same challenges with similar results.

@AMCKenA I am trying to find a paper i once read that was a relatively scholarly article that directly compared sleeve valve with equivalent poppet valve engines. This thread has me thinking about all of this stuff, I have also found a few old emails that have some of the things out of the paper but does not mention its name or Author - most annoying. As there were no equivalent engine to the Sabre, he compared the Bristol Hercules and Centaurus engines to the P&W R2800 and the Wright R1820. There is some comparison of design factors between the Sabre VII, the RR Griffin 130, the RR Eagle 46H22, and the Merlin 130, earlier Merlins and Griffins, the Allison V1710G and the Allison V-3420. The sleeve valve engines did run 1 compression ratio higher than the piston engines, Merlins and Griffins 6:1, Sabre and Eagle 7:1. The Sabre VII had a maximum military rating of 3055hp @ 3850rpm on 100/130 fuel, unfortunately the boost pressure is not shown. The sleeve valve's anti knock capability was demonstrated by the much lower ignition advance enjoyed by the Bristol sleeve valves. I still find it hard to believe the 5500hp. Some calculations put the maximum possible power out of the Eagle22 at about 4300, it only reached 3500hp despite its 46litres. Impulse power is never used in specifying the max output of an engine, the dynos of the day would have taken a while to come back with an accurate power reading. Max power for a few seconds is relatively meaningless as are powers for 'special' engines. For instance the Merlin equivalent of the Rolls Royce R engine was a prewar strengthened Merlin III. It produced a max power of 2160hp at 3200rpm and boost of 27psi At the time the production engine was putting out about 1000hp. It could survive a 15 hour test at 1800hp at 3200rpm and 22psi boost, much better than I would have thought.. It is also much better than the RR R (racing engine) which often had a between tear down period of a few hours. The fuel must have been very special, there was no 120/150 grade or even 100/13 grade fuel at that time. As the engine would not be run for very long, leading of the plugs was probably not much of an issue so i would think there was a lot of lead in the fuel A couple of other things from the paper in my emails (for radials) were, sleeve valve was inherently heavier than poppet due to cooling issues with the junk head, sleeve valve engines about the same frontal area area as poppet valves (again cooling issues). Inline liquid cooled engines are heavier and longer due to wider cylinder spacing required for the layout of the inlet ports. The Sabre was especially heavy due to two large crankshafts, later, the weight was somewhat reduced when the counterweights were removed from the crankshaft design. In the end the paper appears to back the claim of sleeve valve superiority but at a price. Some things that I found very strange about things in the paper, it appears that a contemporary book showed that sleeve valves used about half the oil as the equivalent poppet valve engine, quite the opposite to what has been promulgated in so many stories. Total friction in the sleeve and poppet version was about the same. There was, however, a problem with the sleeves that was due to the mono grade oils available at the time. The Napier used the Coffman starter system. In cold weather, the engines were difficult to start due to high viscosity of the oil, the solution was to start and run the engine every three hours or so, the alternate was truck with a big heater on the back was was used to blow hot air through the chin radiator and warm up the engine. The Napier was difficult to start and many pilots had problems so ground crew would start the engine for them. The Coffman starter really wasn't powerful enough for the Napier. The impulse start caused by the rapid rise of pressure in the starter cylinder put the engine under a fair deal of stress, this was no different for the Merlins that used them. There were 4 cartridges in the Coffman starter. If all cartridges were used and still no start, the ground crew had to remove the plugs and spray a solution of oil into the cylinders to replace the oil that the fuel stripped from the cylinders. When the engines were shut down, at the end there was an injection of the oil solution to keep the cylinders lubricated. This responsible for the cloud of smoke when they were started. When properly built, sleeve valve engines were more reliable than poppets with very long service times. Few wartime engines were adapted for post war commercial use. It cost RR a lot of money to get the Griffin up to snuff for commercial use. It was much easier for Bristol and the Centaurus which had very long service periods. It is interesting that of the last 5 piston engines designed by Rolls Royce 4 were sleeve valve, the only poppet was the Griffin, which followed the line of 36litre engines The Condor, the R, and the Griffin. The air cooled, sleeve valve X24 Pennine was designed to be put in commercial service. So what did RR know that made them shift from poppet to sleeve? I will eventually find that paper and when i do I will post a link.

Also... sleeve valve engines are quieter than sleeveless valve engines. As a result, the Bristol Beaufighter, albeit with Bristol Hercules radials, was nicknamed whispering death.

The wasp major was used in the Convair B-36 Peacemaker which was a post wwii warplane.

I recommended a similar video months ago. Aviation engines are awesome!

your choices are 0 and 1

Ellenor Malik... I can choose my own choice.

B-29 used Wright Cyclones, but the later B-50 upgrade of the B29 used PW 4360's

Yeah, that's what I suspected. The B29 and B50 are hard to tell apart. I think Fifi was used for atom bomb testing, right?

@@HSMiyamoto enola gay (plane #82)(now in the smithsonian) dropped the first atomic bomb, bock's car (plane #77)(now in the wright-patterson air force museum) dropped the second atomic bomb