Genius or insanity? Clickbait titles deserve to be ignored. Buh bye

I flew with my dad in one of these. He was an engineer in WW2 in them. He told me the engines were under powered for the job they had to do. MIss you dad, he left us at 97

The nine-cylinder radial engine has two cam rings. One exhaust, one intake. Each ring has four lobes and rotates opposite the crankshaft's rotation. Also, each cam ring rotates at one-fourth engine RPM. I'm quite familiar with engine mechanics, but this arrangement still amazes me, and I don't fully understand how it works. But it does. The cam rings are partially visible in the cutout. Also they had roller lifters, which are very common today, but unusual for the 1930s and 1940s. Remarkable engineering, and achieved w/o computers, CAD-CAM, or CNC. Those engineers were geniuses. Up close and personal, nothing sounds quite as awesome as a big, radial engine. I got to ride in a B-17 about a decade ago, for $450, and it was worth every cent. I sat in the nose gunner's seat and "strafed" herds of cattle that we flew over in fields surrounding the airport. Quite an experience. No cattle were harmed!

The piston engine planes from WW2 are some of the most incredible engineering in a time of only pencil to paper and slide rules, no computers just pure genius, I love them

I was in the Navy for 20 years, 1970-1990 and worked on 3 aircraft that used the R-1820. The T-28, Grumman S-2 and the Grumman C-1. Always a reliable piece equipment.

As a retired aerospace senior quality engineer, it’s mind-boggling that these engine systems were designed with brain-power, math books, and slide rulers! When looking at the cut-away display engine, the complexity of the gears, cylinder firing sequence, fuel injection, compressed air, and oil distribution systems were all made by manual manufacturing equipment. And interchangeable from different manufacturing companies. Absolutely impressive. 🇺🇸

Radial engines are a fantastic combination of sheer genius and utter insanity.

Several years back, I worked on the ramp when the Collins Foundation was visiting during one of their B-17 and B-24 tours. Both planes started up together and did their engine warm-ups. During the warm-up, you could hear the difference in the B-24's R-1830s and B-17's R-1820s sound. The Wright engines sounded smoother running, versus the Pratt engines which had more of a tick to them. Great engines both, which you could count on in bringing you home.

My father was a ball turret gunner in B-17s in North Africa during WWII. When I was a young kid, he was always telling me that the superchargers and turbochargers on the B-17 engines increased their Volumetric Efficiency(VE). I never knew what that really meant until I took a class in thermodynamics in college. Note: From an online Brian Nutter Tech Article ------ At sea level, the air is more dense. This means that there are more air molecules inside the cylinder. In the mountains, the opposite is true. The same engine would operate at a higher VE at sea level than in the mountains. You can improve VE by making it easier for air to flow. This is the idea behind aftermarket intake manifolds, cold air kits, porting and polishing cylinder heads, and headers. Pumping more air is also the idea behind superchargers, turbos, and nitrous. These power adders force more air into the cylinder. When the fuel and ignition systems are properly tuned, this can raise VE over 100 percent and make tons of power. (From "On All Cylinders" Tech Article 05/11/2017 by Brian Nutter

Grangeville Idaho is home to Aero Motor and they rebuild these engines. I have family over there and I stumbled across this place and was amazed. They gave me a tour and they rebuild everything, heads, crankshafts, all the major and minor assemblies. The dyno run is cool.

I'm not sure which Pratt it was, but many years ago I read an article about the recollections of a WWII German engineer. He said they knew they were in trouble when they dissected a downed P&W engine. They couldn't believe the case halves were so well machined that they didn't need a gasket between them, and worse, that these were being built in high production quantities.

He mentioned Sam Heron, who was a genius whose contribution to aircraft engine development came at a critical time in history. His employment of sodium as a heat transfer medium was paramount in the development of other industries as well. Respect.

I took a ride on the movie version of the Memphis Belle back in 2013 in Wichita, KS. I went with my 83 yr old dad, it was a great time. They flew us for about 45 minutes all around Wichita including flying over the old Boeing factory and our local McConnel Airforce Base. It was exciting because the gunner doors were open and you could literally lean out of the airplane while taking pics and videos. Also, the top gunner's bubble was just a hole that you could stick your head out of as well. An experience that I will never forget. Sadly, my dad passed away only one month later, but, he had a blast on the flight and couldn't quit smiling.

The courage and determination of the air crew is definitely worthy of praise but the ground crews and logistics that kept these planes in the air was nothing short of remarkable. Everyone understood that they had a job to do and lives depended on their getting it right.

The aircraft I worked on in the Navy had 1820-9 radial engines Grumman S-2 Anti Submarine Warfare. This was in early 70s I was fortunate to have a "Turn card" so I could start engines to insure Hydraulic leaks and issues were properly repaired. I loved starting those round motors. Still my favorite engine type to hear run.

My stepfather was an aero engineer and I remember how we looked at a cutaway of a radial, and I exclaimed that it looked insanely complicated and that it must be expensive as hell! But he said no, what is really difficult is making the mould for a V12 block. It requires very experienced workers and that is a major obstacle in ramping up production war-time. All steps in the manufacturing of a radial is a lot simpler. We looked around and found a quite reliable source that stated a price for a Merlin about twice that of an R2800.

One of the big advantages of turbochargers is the ability to vary the amount of boost they produce. In an airplane, this helps to keep engine power constant as they climb, even though the ambient air gets thinner. With mechanical superchargers, there's a single altitude where the supercharger delivers maximum boost. Turbos can deliver constant manifold pressure over a wide range of altitudes, varying the speed of the turbine (and thus boost) by varying how much exhaust was sent through the turbine or bypassed through a wastegate.

When we talk about the bombing campaign in Europe, we often think of the brave crews that risked their lives but we rarely discuss the gorund crews keeping these planes in the air. These old radials were effective and reliable but under war time conditions rewuired a lit of maintenance. Just the 20 hour checks alone were involved. I can't remember the exact interval but around 200 hours, they need top overhauls. They really pushed as much horsepower they could get out of them. My grandad was A&P mechanic on the B-24 but went to school on the B-29. There was a course he took to learn how to do an overhaul blindfolded. This was incase they were in bombing blackout conditions and still had to get the planes repaired. He had a lot of good stories to tell.

I am so glad to see the Memphis Belle restored to her original self. When I was a kid in Memphis, the Belle sat on a concrete pedestal in front of the National Guard Armory located on East Parkway at Central Avenue. There she sat, rusting and deteriorating for years before being rescued for preservation.

What is really amazing about all of these engines, they were designed, and blueprints were all done by hand. The manufacturing process was done by hand. Sheet metal work, casting, forging, machining, all done on manual machine tools. No CAD. Yet you could take any part off the assembly line and fit it to any engine. There was some parts matching, either in dimensions, or in weight, but they did not have to custom machine a part to fit an engine. That is an amazing accomplishment for the time.

On the Wright R-3350 Duplex-Cyclone engines they used exhaust turbines NOT as superchargers. These engines had 3 turbines in the exhaust system(s) that each fed 150 kW onto the crankshaft of the engine. That makes sense when fuel efficiency is more important than performance at height.

That engine was one of the secret weapons of the 8th AF. Bombers returned home with entire cylinders shot away, and the engine still turning. It's a major factor in the legendary status of the B-17.

I was a recip engine mechanic in the Air Force back in 62-66. I worked on the R-2000, R-1300, R-4360 and sometimes the R-3350 PRT. Love sound of those big radials.

The Depth of Mr Duford’s knowledge is astounding - he was Absolutely the Right man for that job!

So many moving parts. Truly incredible

Cutaway: I was surprised at how thin the cylinder walls were. Exhaust driven Turbo and superchargers do actually take a littler engine power to run because of the exhaust back-pressure.

I saw the Sentimental Journey B17 at an airshow in the mid '80s. A couple of interesting things I remember about the engines. 1 was tagged Wright Aeronautical, 2 were General Motors, and 1 Studebaker. The center hub of the turbocharger exhaust bucket wheels were branded Allis Chalmers.

I want to say thank you all for your work, friends. I sent the link to my friend, his grandfather, who served at the Poltava airfield. He was glad to hear and see this plane and the “brave Americans” again. Thanks again. Best wishes. Danny.

The radial engine was fantastic in its design and an amazing piece of engineering,turbo supercharger is amazing.

In a constant speed prop, full power is at full fine pitch where it effectively is just a fixed pitch prop. You use this for takeoff and landing in the event of a go around. Its great advantage is that it can go to feather position in the case of an engine failure. Another advantage of it is the blade shape doesn't need to be as compromised as a fixed pitch where every shape is a compromise. For those that don't know, when in variable pitch mode, the prop RPM is controlled by propeller pitch lever and tacho, the throttle controls manifold pressure. The prop governor infinitely varies the propeller blade pitch (between the coarse and fine stops) to maintain the selected RPM. Say you set 2100rpm and 35" manifold pressure, then the manifold IN HG power setting + RPM + indicated airspeed cause the propeller pitch to vary infinitely to maintain that RPM no matter what - the pitch in this instance would be fairly coarse than if you say changed the manifold pressure to 24" with the same RPM where it would 'fine off' a bit. Usually there is a power setting chart that tells the pilots the optimum combo of manifold pressure & RPM for a given weight and altitude that factors for cruise speed and fuel consumption. When the prop pitch control is the full fine position then the throttle acts as it would in a fixed blade aircraft, or similar to a car throttle where more throttle = more RPM usually. Also re turbochargers, he's dead wrong about it not costing HP. It is a direct engine engine pumping loss. If you're using engine exhaust to pump pressure then you're using power. Work is being done. It is true that the power loss vs a mechanical supercharger is less. Also Superchargers are at a disadvantage on their own, since each revolution delivers a known volume of air. As elevation increases the air can't fill the supercharger so it's effect drops off since it's a positive displacement pump. A turbocharger is free spooling so can provide boost - however it also begins to suffer the effects of altitude gain - as do jet engines. It is a fact of life the higher you go the less power you can make but the fuel efficiency increases due to the fact that you also pick up a lot of airspeed for free. 150 knots indicated airspeed is probably closer to 220 ground speed in still air at say 25,000ft. That's 70 knots of free speed meaning less time to destination therefore less fuel burn.

I’ve got many thousands of hours behind a radial engine, a PW 985. They never let me down in almost 40 years behind them!

Amazing how fast technology changed in a very period of time. The developments during WWI and before II you see so many major developments

1:40 Some Mopar guys are really confused about seeing a hemispherical chamber on an aircraft engine...

The radial engine that blows my mind is the British sleeve radial, Centaurus, no overhead valves, talk about mechanical motion

As they say "If God intended engines to be in-line, Pratt & Whitney would have built one"

Turbochargers are increase their efficiency with higher altitudes since the pressure drop across the turbine is greater as the atmospheric pressure drops. Great system!

I remember the scene in the movie "Memphis Belle" in a raid when a crew member spills a flask of tomato soup and thinks he's bleeding to death.

My father was a waist gunner on a B17 became a flight engineer after the war sat on a wing on a C47 while he changed an exhaust manifold then we taxied down the runway to test the repair. He served in WW II Korea and Vietnam the greatest generation

Fying in one of them on a bombing run must have been scary as hell at 40 below in a non-pressurized plane. The crew must have felt very vulnerable with 109s flying around at about 100 mph faster and flak popping up everywhere. Makes me glad I wasn't born yet.

Navy ADR 2 in the early 70s and loved working on these radial engines. 1800s and 2800s.

My Father was a mechanic on these planes in WWII in the USAAF. There were a lot of farm boys out there that knew their sh.t. He increased horsepower and fuel consumption simply by adjusting the mag timing outside of what the books said.

Samual Heron was born and educated in England attending Goldsmiths College and Durham University. "Heron worked at the Royal Aircraft Factory. From 1915 to 1916 he worked with Professor A.H. Gibson on the first systematic research into the design of air-cooled engine cylinders. They concluded that (1) aluminium should be used for efficient conduction (2) the cylinder head should be in one piece because conduction through metal-to-metal interfaces could not be guaranteed (3) the cylinder head should provide the shortest escape path for heat at the hottest parts across the greatest cross section".

I was amazed when I found out that it was only a single bank radial.

One of the biggest advantages of the turbo supercharger was its ability to maintain the right amount of boost no matter what altitude (though it would gradually reduce once the waste gate was fully closed). A single-stage supercharger was “ground boosted” meaning that it produced way too much boost at low altitudes.. so it was reduced with the throttle. The problem was that the engine had to work hard to produce full boost all of the time. A two speed supercharger had the problem of cutting in and out at certain altitudes. Fly a bit too low and the low speed would cut in, reducing horsepower. The Luftwaffe did solve this by having a hydraulic drive for the superchargers that always ran at the correct speed for the conditions.. as well as having direct injection which allowed for much higher boost levels without detonation. One thing you must remember too about the turbocharger is TINSTAAFL. It indeed costs engine power to operate it.

they were vastly outdated by 1943, but due to the electrical systems being intertwined with the engines it would have cost too much to refit them with newer engines, which is why the G model remained with them while other bombers gained engine upgrades

Speed of technological development at that time is astounding. 1930s...Imagine airplanes just 15-20 years before that..

Radial engines were clearly engineering genius from that era. The low melting point of sodium allowed for better heat dissipation as it sloshed around the internal chamber of the exhaust valve. Not mentioned in the engine description and of interest: all radial engines have odd numbers of cylinders to facilitate the every other cylinder firing order, which even applies to multi-bank engines like the R-2800, R-3350, R-4360. The crankshaft travels in a concentric path around the propeller drive gearing, There is a master cylinder with a fixed connecting rod, while the remaining cylinders have articulating connecting rods.

The issue was the wright was an older engine design but very reliable engine by the time of the war. It couldn’t be easily upgraded to the Pratt and Whitney double wasp more powerful engine, because of all the electric attachments which were essential for the B17. Ironically the Boeing B-50 Superfortress revision of the Boeing B-29 Superfortress, addressed this similar issue by fitting the more powerful Pratt & Whitney R-4360 radial engines post war. MAP had a strategy of power egg or pod, so each major aircraft could be powered by an alternative engine whilst maintaining the specification. This can be argued it was unnecessary over engineering and waste of resources, but it allowed errors to be addressed. Consequently you had the Tempest II Bristol Engined and Tempest V Napier Engined chosen for production, but Tempest I, III and IV design being rejected but ultimately leading to the Bristol engined Sea Fury. The Handley Page Halifax had a similar issue originally with Merlin XX , but incorrectly positioned on the wing resulting in additional drag. This was corrected with the mark III with the installation of the Bristol Hercules with aerodynamic improvements. Handley Page had developed their own design for the power egg instead of using the typical, slimmer Rolls-Royce counterpart; despite generating increased drag, this was a mistake. Obviously the ultimate successful reengineering was the fitting of the Merlin 65 in the outstanding North American P51 airframe.

The “belch!” of oil smoke when a radial starts….

Ain’t nothin like a ROUND Engine !!!

My Dad was a B 24 Driver, he used to talk about them flying 4,000 feet higher and watching the B 17s slowly falling behind as they headed home. The B24s had R2250s.

I read that the Belle was re-engined 9 times in the course of its service life.

all the engineering done with paper pencils and slide rulers. Incredible. Connecticut's Hamilton Standard. Excellent video

Powering the supercharger with exhaust gas probably made it more reliable, too. A perfect link between throttle and boost.

The DWG # and high and low angle info on blades is really important. The hydrostatic prop is ground adjustable. Inside the hub are 2 stop rings . One for high angle and one for low angle . Have degree marks on them.

Gentleman really explained it well how these engines worked

At 9:30 when he is talking about the turbocharger, what he says is not correct. A turbocharger DOES cost horsepower. You can't get something for nothing. The exhaust gases that are coming out of the engine have to do work to get the centrifugal compressor to compress the air going to the engine. The cost is, the pressure in the cylinder on the piston's exhaust stroke is higher (than if there was no turbocharger) because there is resistance of the hot exhaust gases going through the turbine impeller. You can't create free energy.

Then sadly they are looking at the wrong videos, I am lucky to have worked around and flown piston props, radials and big Vs, Generations coming through now never will have that honour to experience, these videos are a contact point for them. Stay safe

Engine output power is proportional to the weight of fuel burned. The proportion of fuel mass (call it weight if you like) to air mass also controls power output. The ideal proportion (mixture) is 14.7:1 (pounds of air:pound of fuel) at which point all the fuel will be burned and release its maximum heating value. Heat is what makes propellers turn. Since air at high altitudes weighs less than the same volume at sea level, the amount of fuel the engine can burn is also less and produces less heat and power. The turbocharger corrects this problem by increasing the mass of air entering the cylinders so that more fuel can be burned to produce more power.

In 1979-80 I got to work on A US-2B Tracker powered by the R-1820-82. That was with a Naval Air Reserve Unit. NARU

My dad used to describe a radial starting sounding like some kicking over empty trash cans in the alley. Aviation Machinist Mate , First Class Joseph Meidlinger.

Excellent video but just one slight issue that i think was put across in a confusing manner. A variable pitch prop is far more efficient than a fixed prop, but can be a lot of work for the pilot. A constant speed prop autonatically varies the prop pitch to keep the engine rpm according to where the pilot sets the throttle. Essentially an automatic variable pitch prop.

Ahhh, the blue ox or Norton. Bombsight or whatever they called it sitting behind the engine is one of my favorite pieces of technology history been fascinated since I was a kid. The engine is borderline insanity, the amount we manufactured and the fact that the b-17 was initially developed in the mid 30s was incredibly interesting to me I was not aware of the fact of the matter. The early thermodynamic principals of the compressors or density accumulators are the reasons we have jets today Edit the pilots

The guy really loves to say "turbosupercharger", and I can't blame him

The radial engine aircraft that I got to fly in were the T-6 Texan, P-2 Neptune, C-118, Stearman, 2 B-17s, and a B-25. One of the B-17s, "Sentimental Journey", had three Studebaker made engines at the time.

That was a really good explanation of superchargers! I finally understood what they were really for; for squeezing the very thin air at high altitude. Thank you for the great explanation!

they didnt catch fire like the 29

It was genius how that Turbo Super Charger operated. It's amazingly what they accomplished back then with Slide rules and no computers.

As for the books I read some 50 years ago. They said that the turbo, produced about 450 Hp, the supercharger took 400 hp to run them so there was a net gain for using a Supercharger system for maintaining Hp up to altitude.

This is the Best episode Yet Scottie !!!

Wow great video. Thanks Jeff for the explanations.

Great series on the B-17 / Memphis Belle. Cheers fm Oz

Turbo chargers cost horsepower too. He is wrong about that.

What a beautiful bird.

I shoked At the Complexity of the Engines 😊

My dad was flight engineer on B17 ww2, 3 bail outs and one of the few survivors

Great job explaining the engine design especially the turbo charger/super charger system

@6:29 B17 engines are the best white noise ever!

having ridden in two different B-17s, one being the Memphis Belle Movie plane shown in the first clips of this video, I have to say, they are worth the money to take a ride in.

Highly interesting! Tnx. alot!

The mayor of Memphis, elected in 1991, was responsible for letting this iconic B17, the Memphis Bell, leave its eponymous home city. What a loss and what a waste. As a kid of about 12, I played inside this bomber as it sat at the Memphis airport. It was restored and placed on Mud Island. I guess it wasn't worth keeping in its home city.

A turbo does rob power from the engine just like a supercharger, it's just taking it from a different place. If you're using engine exhaust to turn a fan, you're increasing the pressure the engine has to push exhaust out, thereby working against the piston stroke trying to push the exhaust out and slowing the engine down.

ITS ALL ABOUT AIR DENSITY

Great episode. One of the Best Ever!!!❤

My dad worked on these as a corporal in the army air corps back in WW2...called out wrong engine sounds he heard in any war movie we watched...

The reason for a double compression system is because as elevation increases, air gets thinner so a supercharge will lose efficiency while the turbocharger will spin faster and keep pumping BUT the turbochager can't get enough pressure w/o becoming too big but the supercharger can.... Even today this system is used, see Archates engines and their tank engine developed in partnership with Cummins

Exhaust driven turbochargers do take power to turn. Excellent video and so informative. Just wanted to correct a minor point. Very good video. Wow what a fantastic era. Pretty much the height of I.C.E. technology. And besides the technology, the unbelievable manufacturing accomplishments have never been completely acknowledged. A good book about it is: Freedom’s Forge. Thank you for this great video you’ve made here

A couple of days ago I walked by a B17 bomber ----and a B29 bomber right next to it. Not far away was an SR71 aircraft, the fastest in the world. Nearby was a reconstructed 1903 Wright Flyer. These were among many other aircraft. Where was I?

Extremely interesting, thanks.

Density of air, which is 20% oxygen, decreases with altitude. This means the engine gets less oxygen at altitude, leading to less power because it is the fuel/oxygen chemical reaction that makes the power. By compressing the air, we are re-densifying the oxygen making it possible to generate as much power at altitude as can be made at sea level. That's how it works.

Very fine explanation by this gentleman, and really makes me want to visit the museum. Thanks!

My father was an aircraft mechanic during ww2. He inspected those engines for sabotage before they were sent to Europe.

Is that the original Memphis Belle? The one that used to be on display at Mud Island in the Mississippi River in Memphis? I remember seeing that plane back in the early 70s. Then a couple of years ago, while visiting my son in England, we went to the Imperial War Museum in Duxford and saw a B-17 all painted up in the Memphis Belle livery. It started up and took off with paying passengers. What a thrill that must have been.

Amazing video, thank you!!!!!

The "tour guide", or whatever he is, did not explain why supercharging was important, he stated that it was important. Because high altitudes meant lower oxygen levels supercharging was needed to force more oxygen into the combustion chamber. This same type system, crank drive supercharger and turbo supercharger, was used in the P-47, giving it unparalleled high altitude performance.

Yamaha used sodium filled valves on some of their dirt bikes starting in the late 90s,....and I thought it was some brand new technology at the time. 😂

Sencillamente IMPRESIONATE!!!

Well done and accurate information.

The turbo adds back pressure on the exhaust cycle so....not free. But the waste gate allows for greater flexibility.

Well explained! Bravo!