B-17 ENGINES IN DEPTH! Genius Or Insanity?

[@petergibbons607]

i guess you took an interesting subject and challenged yourself to make the video about it as boring as possible, you succeeded because i really want to learn about this engine but i can't handle how boring you made this video.

[@MilitaryArmamentsCompany]

We look forward to seeing your production series of videos on the Memphis Belle.

[@HH-COactual]

Did you not take your Adderall to stay focused enough on this one? Not enough colorful pictures and flashy lights?

[@Goldscare]

Keep watching SpongeBob, son. This isn’t the channel for you.

[@petergibbons607]

@@Goldscare SpongeBob is even more boring and I have no interest in that. I do enjoy stuff on engineering and most people do a good job on that but not this video. Sorry y'all can't handle criticism, it's your loss.

[@petergibbons607]

@@MilitaryArmamentsCompany i was trying to tell you to do a better job next time but you're not listening. just out of curiosity i checked and saw that you only have 18k subs, that's pretty much pathetic and now it all makes sense (the boring video and your reaction when i told you so). i don't actually care if your channel does well or not, i was trying to help you out but you don't deserve it, so just keep doing what you're doing ;)

[@claiborneeastjr4129]

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!

[@MilitaryArmamentsCompany]

On one hand it's UFO technology, when you look into it, it's amazingly simple to understand compared to today's engines. Thankyou for watching! Glad you got a 17 experience flight in!

[@dukecraig2402]

Roller lifters were only uncommon in automobile engine's back then, every motorcycle engine I've seen the inside of from the mid teens up had roller lifters even the flathead motorcycle engine's. The only reason I can think of why the automobile industry used flat tappet lifters so extensively is because with them you don't have to solve the rotation issue like you have to with roller lifters, it simplifies the design, aside from that I couldn't guess as to why they used flat tappets in their engine's when it seems like everyone else used roller tappets.

[@claiborneeastjr4129]

Good reasoning. Likely flat tappets were cheaper to manufacture, too.@@dukecraig2402

[@PhrankTube]

Each cam ring operates at 1/8 engine RPM . . . . . not 1/4. Each cam ring does, indeed, rotate opposite the crankshaft's rotation. You're right . . . . these 1820s were a work of genius!

[@claiborneeastjr4129]

Thanks for that correction.@@PhrankTube

[@scottwins2]

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

[@MilitaryArmamentsCompany]

Incredible to have a memorable experience like that. If he was an engineer check out our top turret video in the series.

[@GuidosDad]

Beautiful Memories 🇺🇸 God Bless him 🙏

[@prophetsnake]

Then your dad was wrong.

[@HH-COactual]

​@@prophetsnake A WW2 B-17 Veterans opinion counts for a lot, right or wrong. Here's a Prophet for you Prophet Snake, your opinion doesn't matter.

[@prophetsnake]

@@HH-COactual Then you are a liar. And guess one, one of us has flown an airplane powered by 1820s, and it wasn't you.

[@redr1150r]

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.

[@MilitaryArmamentsCompany]

I had no idea the engine was in service that long. Very impressive.

[@bobharrison7693]

Yup. Although I was a jet guy, I was lucky enough to fly all 3 of those birds. Great engine.

[@redr1150r]

@@bobharrison7693 I also worked on a EC-121 Lockheed Constellation in my first squadron. I also worked on the F-4, A-3, A-4, H-2 helicopter, A-6 and the F-4. I carried 5 aircraft NECs. The first squadron I was in, VAQ-33, had 4 different aircraft types. I was also on the Forrestal (VA-85), and Nimitz (AIMD). I worked on the F-14 at the Depot in Norfolk and just retired from the Coast Guard Depot in Elizabeth City, N.C. on Dec. 31st.. I'm 72 and it's all I've ever done. I was also raised on Naval Air Stations until I joined the Navy.

[@GuidosDad]

Thank you for your Service 🇺🇸 a Fascinating time in Aviation

[@basiltaylor8910]

You forgot the Grumman HU-16 Albatross Rescue Amphibian, burning 115\145 grade avgas its twin late model R-1820 Cyclone 9,s had a pony count of 1525 for take off, not bad for a single row radial partly designed by Ex Armstrong Siddeley Engineer S,D Heron in the late 1920,s .

[@JodyMackin-w9g]

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

[@westerncivilization]

all accomplished without what modern society calls "diversity". it is amazing what our people can accomplish when left alone.

[@mikes9759]

Absolutely! And the time constraints on top of it!!

[@mikes9759]

​@westerncivilization And sadly we gave a lot of things away!!

[@87mini]

@@westerncivilization That's a pretty silly statement. Do you mean made by white people?

[@87mini]

@@mikes9759 Britain gave a lot to us, too. But if you agree with him, I don't expect you to think past your comfort level...

[@stevesmolik24]

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. 🇺🇸

[@MilitaryArmamentsCompany]

You are absolutely right, unbelievable some of the things we come up with.

[@johncox2865]

@@MilitaryArmamentsCompany Today, we celebrate the prospect of losing the ability to do such things. How? We are inviting Artificial Intelligence into our lives.

[@clivelee4279]

Take a look at a cut away of a Bristol sleeve valve radial if you like complicated .

[@ericsmith1562]

Truth!

[@rcdogmanduh4440]

They were made by Machinists. lol look that one up, not green button pushers! What an incredible trade!

[@chrisweber5399]

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.

[@ralphcarroll5090]

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

[@MilitaryArmamentsCompany]

First rate description! Thankyou for the information. Stay tuned with us, a huge Ball Turret video comes in 2 weeks. It will be the best one on the internet.

[@jamesnoggle2661]

great description. That thinner air was much easier to fly through. All the trade-offs; burning the fuel to get up there, saving fuel by being there, less accuracy in bombing, which led to development of better bomb sights, then almost gliding back to base.

[@scottw5315]

Normally aspirated, meaning non turbocharged/supercharged, lose about 3% power per every thousand feet of altitude gain. With the use of turbochargers and superchargers or both on the B-17, the engine can develop sea level thrust up to a certain critical altitude dependent on their design.

[@LanceStoddard]

Setting boost pressure to the proper level ensures the proper compression. It takes time to put air into a cylinder. As RPM's go up, time goes down. Compressors fix that problem.

[@HughBond-kx7ly]

Reciprocating gasoline engines produce more power on cool days than hot days ,I guess everyone knows that but what about the troposphere being 50 percent thicker at the equator than in temperate latitudes, I wonder how that fits into the equation.

[@Turboy65]

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

[@MilitaryArmamentsCompany]

Someone who finally understands my well thought out title! Welcome to the channel my friend.

[@prophetsnake]

@@MilitaryArmamentsCompany Another idiot, in other words

[@331SVTCobra]

@@MilitaryArmamentsCompany I don't see the insanity though. Everything in the engine made sense. It was a smart evolution of the ICE, optimized for higher altitude. Gamers and armchair generals don't appreciate the value of America's compression technology. Our aircraft could operate at 30,000 feet while the Germans struggled to be relevant at 20,000 feet. Germany's lack of supercharging meant they had to have huge displacement engines, at a cost of range. Thanks to the automobile manufacturers' understanding of materials, critical engine components were made from specific alloys, tricks like sodium-filled valves to combat predetonation, and of course the materials to build 20,000rpm blowers and knowing the appropriate boost settings all played a critical role in dominating the air. The B-17 airframe is so classic. It's fun to daydream about a civilian B-17 that is powered by two turboprops. That would be the ultimate Rich Person's toy.

[@jean-mariejm7404]

Two turboprop DC3 do exist. Great plane

[@terrygates8546]

Genius for sure then they had double rows before jet age

[@ohger1]

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.

[@MilitaryArmamentsCompany]

American industry in High Gear right there.

[@prophetsnake]

Then he was lying. The Germans were building licensed copies of Pratt and Whitney engines before the war.

[@kenneth9874]

​@@prophetsnakethey didn't have a licensed R2800.

[@HughBond-kx7ly]

​@@prophetsnakeyes for the JU 52 3m.

[@prophetsnake]

@@HughBond-kx7ly For a lot of airplanes.

[@michaelalbert8474]

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.

[@MilitaryArmamentsCompany]

Very true. Agreed!

[@Texas40years]

My dad was an aircraft powerplant mechanic during WW2 based in India. They would do the maintenance and overhauls of the engines. One thing that my brother reminded of was that once an engine was ready to go back into service, that engine, using a test stand, was run at full throttle for 24 hours before it could be put into an aircraft.

[@michaelalbert8474]

@@Texas40years Better to break on the stand. 24 hours seems like a lot. They earned their title of “greatest generation”.

[@jean-mariejm7404]

Very true. On the other hand the Germans had engines manufactured by forced workers and prisoners, with lost of sabotaged key elements. Also courageous resistant people.

[@richarderickson8840]

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.

[@clintwilde1048]

I also worked on these engines from S2's. We had one catastrophic failure of one engine where a cylinder came loose, the piston on the bottom of its stroke came out of the cylinder, and the crank tried to push it back in, smearing it like butter. We salvaged everything off of that engine we could, but the front crankcase half, the crank and the master rod with the one slave connecting rod we could not get out, was put in the recycle bin.

[@88SC]

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.

[@MilitaryArmamentsCompany]

Yes absolutely. Jeff was the right man for the job on this topic!

[@Snaproll47518]

Sodium, having a low melting point, would slosh around inside the valve to improve heat transfer.

[@basiltaylor8910]

Wow every day is a school day, Sam worked for Armstrong Siddeley Motors of Coventry Warwickshire UK, for he designed the Jaguar first half way reliable twin row radial in the early 1920,s.

[@peterclark6290]

Should be called Heron valves.

[@basiltaylor8910]

@@peterclark6290 I think you are right, with out Sam,s breakthrough, we could not have won the Battle of Britain,. Rollers of Derby used sodium cooled exhaust valves on the Merlin and Griffon, enabling high power ratings with improved reliability.

[@mindeloman]

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.

[@MilitaryArmamentsCompany]

Great information. Welcome to the channel! Ground crew of course need time in the spotlight. Hopefully we can cover them in depth. Also the guys back him working tireless hours with coke bottle lens glasses and a drafting board to make ideas become reality. I have full B-17 plans. 21000 technical drawings in there.

[@Roybwatchin]

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.

[@MilitaryArmamentsCompany]

Glad you got to experience a 17 ride! With you dad makes it better. Check out our video on Bomber Camp, Lots more happening in a B-17 then just the ride!

[@williamrau8636]

She caught fire a few years back and burned up in field near Chicago I’m told. A real loss.

[@Roybwatchin]

@@williamrau8636 I believe that B-17 was the Nine-O-Nine that crashed in Connecticut in 2019, I believe the Memphis Belle that I flew on is still flying, at least I hope so, I'll do some checking now.

[@davidscott9572]

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

[@MilitaryArmamentsCompany]

Thankyou to him and Thankyou for watching

[@steels96]

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.

[@MilitaryArmamentsCompany]

Thanks for watching mate! Plenty more coming! Its B-17 season currently however tanks will make a big appearance again soon.

[@pete1342]

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.

[@MilitaryArmamentsCompany]

Amazing you remember those details! There's Passion in the subject right there.

[@rolandsolomon7728]

I flew on the Sentimental Journey in July of 2013 in the nose. Navigator and bombardier seat. What an experience! And I checked that one off of my bucket list. 😊

[@GuidosDad]

Isn’t it WONDERFUL ? We are Blessed to have done It

[@philgiglio7922]

ALL such flights are now no longer allowed because of a recent B17 crash that took multiple lives. IIRC it was pilot error The FAS is not allowing these pay to fly flights any longer

[@rolandsolomon7728]

@@philgiglio7922 That's why I flew on one a long time ago. I saw the writing on the wall even back then thinking that insurance companies were going to stop allowing it.

[@randall1959]

So many moving parts. Truly incredible

[@donallen7990]

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.

[@MilitaryArmamentsCompany]

Absolutely a one of a kind sound!

[@drtidrow]

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.

[@danquigg8311]

Isn't there a 'waste gate' or a 'bleed gate' between the 'charger and the engine to allow the correct boost to the engine & either bleed or waste the excess compressed air?

[@drtidrow]

@@danquigg8311 You're probably thinking of a blow-off valve like that found on cars, but that's mainly for cases when the throttle slams and leaves the boost air nowhere to go. Aircraft engines generally operate at mostly or wide-open throttle, and don't have times where the throttle slams closed like when you shift a car's transmission, the throttles generally stay at a particular setting for long periods of time. Wouldn't surprise me, though, if there was a blow-off valve in the intake somewhere to deal with transients.

[@wilburfinnigan2142]

@@danquigg8311 He said there was a waste gate to control volume, go back and reread his post, s l o w l y !!!!!

[@kenneth9874]

They added different stages and multiple speed mechanical superchargers to extend the altitude ranges

[@wilburfinnigan2142]

@@kenneth9874 the B17 has a single stage mechanical superchrger which is fed by a TURBOcharger, no gears or speed, same as B24 and the P47 and the P38 only planes in WWII to use a TURBOcharger, which is a turbine driven by the exhaust gasses !!!

[@rongreen8485]

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.

[@MilitaryArmamentsCompany]

Very cool! Didn't know there was a place in Idaho for that. I would imagine it's a rare skill set to maintain.

[@GereDJ2]

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.

[@YouNameItGaming]

Exactly! The turbine wheel, and the plumbing leading to it (diameter/density changes, bends etcetera) all creates resistance against the piston trying to push that exhaust out, but people seem to forget that as you're forcing more air (and flowing more fuel) to produce much more power than it costs. It creates a bit of a deadly circle with turbo-superchargers (and modern-day turbocharging) as the more air/fuel you force into the cylinders, the more exhaust gases need to come out, and therefore more back-pressure

[@GereDJ2]

@@YouNameItGaming I always thought it was really neat how Boeing tucked the landing gear inside the rear of the engine nacelle. Seemed to work well even with a bit of the tire showing. Amazing how the B-17 was state-of-the-art at its important place-in-time. And, one of the only things the Damn Ruskys didn't copy.

[@scotty2307]

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.

[@MilitaryArmamentsCompany]

Agreed! Glad you enjoyed the video.

[@scotty2307]

I have a friend that owns both a Harvard T-6, and a T-28B. He has quipped on a few occasions that a radial engine is the best means of turning money into amazing sound.

[@wilburfinnigan2142]

Yes and Packard showed RR how to build precision engines on mass productions also in WW II !!!

[@robinj.9329]

We living today owe an incredible debt to all of the millions of young men and women who contributed to the Winning of WW2

[@MilitaryArmamentsCompany]

Absolutely agreed!

[@Caseytify]

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.

[@MilitaryArmamentsCompany]

Absolutely. Agreed.... the insanity of believing it would work and the genius in making it a reality.

[@GazzaLDN]

Got any references for that on 4 engine bombers? Surely the pilot would shut down a damaged & overheating through oil loss engine and fly home on 3 or two engines, rather than risk a fire and catastrophic wing failure.

[@cafhead]

Yup and the big wing helped a lot as well Large pieces cpuld get shot away and there would still be enough wing to get home. A fanstastic and rugged airplane.

[@cafhead]

References?! Lmao

[@ThePaulv12]

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.

[@chrisstaples182]

As someone who has thousands of hours in radial engine airplanes and an AME, I find many flaws in your statement on how these engines work.

[@ronyoung3623]

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

[@jmurphy1973]

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

[@dougthompson1598]

Hemispherical combustion chambers go WAY back, at least to 1901 for car engines.

[@wilburfinnigan2142]

Mopar did NOT invent the hemi, they just used it !!!

[@jayh1734]

Lots of engines used it. To me, it's the ardun ohv conversions for the flathead ford's. They sound so cool. The first ford escorts were hemis with the 1.6, later replaced by 2 versions of the 1.9. All junk. But the escort had a 1.6 hemi!!!!

[@richardromano6163]

Really enjoy learning about these B17 and the engines.awesome engineering and the turbo and 1930s technology and to the brave crews who flew them and forget the crews on the ground who kept them flyjng.Thanks again

[@MilitaryArmamentsCompany]

Thanks for the kind words and supporting the channel.

[@jenningsrozzell7557]

I was raised by my paternal Grand-Aunt, stories of her time in a war factory building B-17's (radio section) and mounting the engines. Bestest history teacher I ever had... miss you much Aunt Nannie.

[@GuidosDad]

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

[@richardpayne5101]

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

[@jimduffy1967]

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

[@MilitaryArmamentsCompany]

Glad you enjoyed the video, check out the rest of the B-17 Series.

[@stettan1]

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.

[@MilitaryArmamentsCompany]

Very interesting perspective. What could that say about the British using their V blocks in medium and heavy bombers even though they had radial engines as well? Would their design be more complicated and more expensive then the US counterparts?

[@mylanmiller9656]

@@MilitaryArmamentsCompany It depended on what side of the Atlantic the Merlin was built , if it was built in Briten it was a hand built engine. if it was a Packard Merlin, it was built on a assembly line just like all other American engines. Yes the British Merlin Production was up and Quality control was just as good, and sometimes better than the British engines.

[@waynemanning3262]

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!

[@MilitaryArmamentsCompany]

Hell yea! Love radials. We see them in the tank world as well.

[@BernardBouchard-qq9kq]

I built a Beaver 985 with all new parts to send to Berlin it was beautiful.We got theA.F. to fly it in they loved it.

[@kmbriggs2693]

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.

[@tramlink8544]

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

[@bobharrison7693]

Out dated? The R-1820 was used up into the 1980s on the Navy C-1.

[@tramlink8544]

youre comparing a non direct combat aircraft that hunts submarines with no risk of air to air action with a direct combat heavy bomber that saw action against enemy fighters. the engine was outdated for the use on heavy bombers the RAF and USAAF continuously throughout the war updated the powerplants on all their bombers, even the B29 had two engine updates, yet the B-17 was stuck with an engine first designed in 1930s when there were other radial options that could have aided the B-17 but couldnt be implemented because of bad aircraft designing by boeing on the part of electrical systems@@bobharrison7693

[@timothybruggeman9332]

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.

[@petermuller161]

It’s a commonly held myth. Of course turbos cost power

[@wilburfinnigan2142]

timothy that pressure in the exhaust due to the turbocharger is called BACK PRESSURE and yes it does cost some horsepower but the turbo more than makes up for it actually increasing the HP .

[@GazzaLDN]

Don't think the fella interviewed explained why they used Turbo-charging at all well. Turbo-charging was one way to go, others went with two staged super chargers.

[@Snaproll47518]

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.

[@MilitaryArmamentsCompany]

Excellent information.

[@jameskelly8506]

I worked and flew on a B-17 with Intermountain Aviation during the sixties. The engines were extremely dependable and easy to maintain.

[@MilitaryArmamentsCompany]

Absolutely. Beautiful engines. Thanks for watching.

[@geeeeeee3]

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

[@MilitaryArmamentsCompany]

Thank you very much! Glad you enjoyed it. Please check out the rest of the series.

[@GuidosDad]

This is the Best episode Yet Scottie !!!

[@MilitaryArmamentsCompany]

What makes this one stand out above the rest?

[@GuidosDad]

Round Engines turning gas into Noise !!! 😊-👍🏻

[@GuidosDad]

U ok ???

[@167curly]

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.

[@DC.409]

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.

[@bobharrison7693]

The R-1820 in the post war Navy E-1A (ne WF) Tracker was rated at 1500 hp.

[@GuidosDad]

Ain’t nothin like a ROUND Engine !!!

[@GuidosDad]

Especially when it’s on a B-17 !

[@montylc2001]

Proper term is "radial".

[@GuidosDad]

😆 thanks man! I restore old airplanes for a living - including a B-17 ( with 4 Round engines ) 🇺🇸

[@GuidosDad]

It’s a term airplane guys use

[@montylc2001]

@@GuidosDad really. I'm an A&P mechanic.

[@daletesson4630]

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.

[@MilitaryArmamentsCompany]

Very cool! Yes she's in the best place she could be now!

[@shoominati23]

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

[@PortsmouthCherokee]

Thats hillarious lmao

[@nickkercheval2704]

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

[@MilitaryArmamentsCompany]

Thankyou for watching and for the kind words. Glad you enjoyed the video.

[@xvdd1]

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".

[@MilitaryArmamentsCompany]

Very interesting.

[@88SC]

And he wrote a whole book explaining these developments and others. History of the Aircraft Piston Engines: A Brief Outline. Published in 1961. A must read for motorheads. It’s not cheap if you can find a copy.

[@Ugottabekiddi]

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

[@1fandik]

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

[@MilitaryArmamentsCompany]

Absolutely. Part of the "Genius" in the title.

[@jefferymeyers2737]

My Grandpa as born in 1902 ,he joined the Army Aircorps when he was 17 years old .Pop was a crew chief on the early bombers when the Army hauled mail up and down the east coast winter and summer. He told me he was crew chief with Curtis LaMay when the Army flew the first B17 . He survived WW2 served in England and the Philippines. Grandpa served 30 plus years and Air Force Civil Service until he retired. Miss ya Pop and all the stories you would tell your Grandson

[@MilitaryArmamentsCompany]

Oh wow! He was most certainly part of the whole B17 story! Taking a guess here he was in the Martin B-10s pre war? There is only 1 of those left in the world. He would have seen all the B-17 models in service. We are glad to have you on the channel!

[@jefferymeyers2737]

@MilitaryArmamentsCompany Funny yes Martin's amd many more ,He knew Hap Arnold, Jimmy Doolittle,Curtis Lamay and crew chiefed their airplanes when they were Lieutenants, my mom recorded some of his stories but not all. He died in 1992 ,his nic name was Crash Miller after WW2 he was stationed in Az when he ran into an another guy that called his Crash he told them never repeat it again at Williams Field Az.

[@chopper7352]

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

[@MilitaryArmamentsCompany]

Glad your enjoying the series mate! We need more Aussies on the channel. Scott has big plans for film work in Australia soon. "G For George!"

[@chopper7352]

@@MilitaryArmamentsCompany Cheers. It's been a few years since I last visited Canberra & the AWM. "G for George" is a great exhibit. I'm now based in Perth & the RAAF Museum here also has a beautifully preserved Lancaster, as well as many other WW2 aircraft....PBY Catalina & Spitfire to name just a few. Take it easy mate. Cav all the way !

[@MilitaryArmamentsCompany]

@@chopper7352 You work with that Lancaster in Perth? How can i get hold of you?

[@chopper7352]

@@MilitaryArmamentsCompany No mate, I don't work with it. I've just been a visitor to the "RAAF Association Bullcreek Museum" a few times over the last several years. I'm keen on all things Military History, be it Army, Airforce or Navy (especially WW1 & WW2). The museum does allow a few visitors at a time to go inside for a look & experience the various crew positions, but that is a higher tier $ ticket. Maybe for my next birthday. I do like the idea of maybe one day being a volunteer at either the Fre'o Army Museum (they've got a good number of AFV's) or the RAAF Museum, but that's approx 10 years away, unless I get lucky with Lotto / Powerball. 😂 Keep up the great work over there. Cheers

[@dovepond]

Excellent description of technical terms.

[@MilitaryArmamentsCompany]

Thanks for the kind words, glad you enjoyed it.

[@bobfeller604]

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

[@MilitaryArmamentsCompany]

We have a future video coming out on the Belle and all its in field Mods and upgrades.

[@SpecialEDy]

The statement that turbo superchargers dont use engine power is false. Turbochargers are driven by the exhaust stroke of the pistons, they generate parasitic loses. Turbochargers cause backpressure in the exhaust system, and the crankshaft has to apply energy to drive the piston upwards on the exhaust stroke to force air through the turbocharger. It is not free energy.

[@garethbarry3825]

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.

[@MilitaryArmamentsCompany]

Interesting feedback. Always learning here. Thankyou for watching.

[@Zupdood2]

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!

[@MilitaryArmamentsCompany]

Glad you enjoyed. Thankyou for the kind words. Plenty more on B-17

[@jackmoorehead2036]

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.

[@GuidosDad]

I Had dear friends who had flown both the 17 and the 24 - I loved how they’d bust eachothers ballz… the best wisecrack I recall was a 17 pilot who said the B-24 was the Box a B-17 came in 😁 I love them both / been fortunate enough to have flown in both

[@PhrankTube]

The B-24 had Pratt & Whitney R-1830 twin row 14 cylinder radial engines.

[@MilitaryArmamentsCompany]

We have big plans to cover B-24 as well! "Diamond Lil and Strawberry Bitch." Let us know what you want to see from them.

[@basiltaylor8910]

Wrong the late model Flying Whale were fitted with turboed Pratt& Whittney R-1830 Twin Wasps, similar to those in the DC-3 C-47 Dakota 'Gooney Bird' and Bristol Beaufort.

[@highwatercircutrider]

My grandmother was a ‘Rosy the Riveter’ at Willow Run B24 bomber plant near Detroit, Michigan. She used to tell of writing notes on chewing gum wrappers. She stuck them between the aircraft’s ribs and skin to encourage air crewmen later.

[@cramersclassics]

As a pilot and aircraft builder this is a good explanation. Even more detail would be great. Subscribed.

[@MilitaryArmamentsCompany]

Thankyou for the kind words. Welcome to the channel. Unfortunately we only had 3 hours with Jeff, in which to cover the entire daylight bombing campaign, crew stories, along with most of the Memphis Belle story. Perhaps one day we can dive deeper into the engine.

[@oldtugs]

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.

[@philgiglio7922]

I find it interesting that the proper air fuel ratio is the same number as the weight of air pressure at ground level...14.7 psi

[@oldtugs]

It is an interesting coincidence but only the per square inch bit and don't forget that is 14.7psia absolute pressure. The ratio is the same in kilograms or tons or ounces. Reciprocating aircraft engines have adjustable mixture controls because an economy mixture is just over 15:1 and highest power is around 12.5:1. Different fuels have different ratios, natural gas for instance is around 10:1.

[@02448-s]

I went to Aviation HS in NYC. We had R1340s and R2680s on stands in our engine shops. R2680s are two 1340s in tandem. Very imresive looking to a 16-17 year old kid. Loved the video. Thought 17s would have had the dual row radial engines.

[@MilitaryArmamentsCompany]

Very cool! Remember the 17 is an early to mid 30s design. Double row did not exist yet. Rather then drastically redesign the 17, efforts focused on a total new Platform such as B29

[@andrerousseau5730]

Your description of turbochargers omits any mention that no automatic boost-control system was used.

[@dukecraig2402]

Yes they were automatic, that's why the air filters had to be disengaged above 15,000 ft on the F and 20,000 ft on the G model, because they'd restrict air enough in the thin atmosphere that the automatic boost control would overspeed the turbo's trying to automatically maintain boost. Like other USAAF aircraft in WW2 that had the supercharger/turbo configuration they had automatic boost controls but could also be run manually by turning off the automatic feature.

[@GuidosDad]

🤓

[@tfogelson3139]

One of the things you never hear about in discussion on these engines is oil burn. On the B-17 that I worked on a good engine was 2 gallons an hour. I think I read in the manual that when it got to 7 gallons an hour it was due for an overhaul. I am betting none of the planes in combat ever got to that point before being damaged.

[@MilitaryArmamentsCompany]

Great point, yes we did not get to discuss that. We have had experience seeing it first hand on planes at Bomber Camp. Great feedback!

[@dennislear3336]

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

[@wilburfinnigan2142]

Over engineered, overly complicated, and very expensive to build and maintain !!!

[@majorbobbage3356]

Great video, thank you. ( I might add, for those who still don't get it, fuel and air has to be introduced to the engine in a specific ratio. When the air is thinner it means less fuel so therefore less horsepower. Compressing the air allows more fuel also, therefore maintaining or increasing the horsepower). Definitely going to have to see if there's more videos on this engine by you guys, obviously the turbo and the props are just one aspect, thx again.

[@MilitaryArmamentsCompany]

Great information great feedback. We had limited time with Jeff unfortunately and we had to power through most subjects. Perhaps another time we will be able to dive deeper.

[@dennisyoung4631]

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

[@MilitaryArmamentsCompany]

Love it!

[@GuidosDad]

Damn Skippy !!!! 💨

[@flyingfortressrc1794]

Wow great video. Thanks Jeff for the explanations.

[@ForceOfChaos1776]

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

[@MilitaryArmamentsCompany]

Glad you enjoyed the video. We have plenty more coming on the subject.

[@ancliuin2459]

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

[@MilitaryArmamentsCompany]

Thanks for watching! Please check out the rest of the B-17 series to see more of the Belle.

[@njseashorechas2698]

These engines are amazing! All the parts , hours of design and machining blow my mind! I'm still in disbelief how they would stay together. Its a real treat to hear the ominous sound of the radial engines when the air show is in town. Must have been scarry as hell if you were on the ground in WW2!

[@MilitaryArmamentsCompany]

Agreed, our title eluded to that insanity of believing we could take a Tonne of Bombs to 30,000 ft when only a few short years prior we could not fly at all. The Genius was making it all a reality.

[@zillsburyy1]

they didnt catch fire like the 29

[@davidzak538]

The sound of these engines is so COOL!

[@MilitaryArmamentsCompany]

Agreed! Radials are a category of their own!

[@feedingravens]

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.

[@philgiglio7922]

These were the engines used in the Constellation and the Super Connie. Also I think the A1 Skyraider... the warbird I wish I owned

[@BernardBouchard-qq9kq]

I worked on army aircraft at Burtonwood near Liverpool where 12 oclock High was filmed you could still Feel the ghosts in the giant hangars.

[@MilitaryArmamentsCompany]

Very cool!

[@edzhead22]

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...

[@MilitaryArmamentsCompany]

Hell yea. That's a skill you cant buy!

[@scootergeorge7089]

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

[@gj1234567899999]

Hypothetically, if they replaced the R1820 radial engines of the B17 with the r2800 engines what kind of performance boost would you get?

[@MilitaryArmamentsCompany]

Love the creative "what if" thoughts. That one is definitely above my pay grade. Some one here may know.

[@wilburfinnigan2142]

@@MilitaryArmamentsCompany Well the B17's engines were listed as 1200 HP ea and the R2800 in basic form was 2,000 And depending which R2800 and the supercharger used, either the single stage, or 2 stage 2 speed unit or the 2 stage Turbocharged version to determine service ceiling and load !! !

[@mchume65]

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.

[@MilitaryArmamentsCompany]

Great stuff! You know a round engine when you hear one!

[@ttip9411]

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. 😂

[@Nivola1953]

I noticed in the background a Regia Aeronautica Macchi (pron. like makki 🙏🏻) MC 200, (at 11:26 can see the front with characteristic bulges on the cowlings) that’s quite rare!

[@MilitaryArmamentsCompany]

Good Eye.

[@tgorski52]

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

[@franksizzllemann5628]

But turbo adds front pressure - just being argumentative

[@tgorski52]

@@franksizzllemann5628More air means more fuel means more power.

[@dougthompson1598]

Gale Banks has a great video exploring this, and a well-matched turbocharger is remarkably less restrictive than most of us gear-heads have thought. Not exactly free, but close. By contrast a mechanically driven supercharger imposes a constant resistance to crankshaft rotation

[@JohnDickson-j3g]

Can't see what is boring,good explanation of how it worked, what more do you want? John Dickson

[@MilitaryArmamentsCompany]

Thankyou for watching and supporting the channel.

[@totalyep]

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

[@badboyvr4]

You're wrong, even in motorsports engineers and mechanics consider turbos free horsepower, like he said, it's driven by the exhaust which is already there.. A supercharger costs you horsepower because it has to mechanically driven by the engine, like the belt driven supercharger in my 2010 Cadillac CTS-V car.

[@totalyep]

@@badboyvr4 nope not true. The exhaust back pressure from the turbo makes the engine work harder to push out the exhaust. It takes a lot of energy to compress 1000 cfm of air to say 15psi. There is no free lunch in this world.

[@carlosfabianmaciel9643]

Sencillamente IMPRESIONATE!!!

[@MilitaryArmamentsCompany]

Thankyou!

[@craigpennington1251]

So these engines were compounded according to the explanation given. Interesting. I was under the impression that turbo compounding came later. Great video. Thanks for posting.

[@MilitaryArmamentsCompany]

Glad you enjoyed it! Plenty more coming.

[@Dr_Reason]

To be compound, the turbine should be geared to the output shaft. This turbo feeds the engine driven centrifugal supercharger. Really awesome though.

[@wilburfinnigan2142]

@@Dr_Reason Making it a 2 stage supercharging system, More than the British Lancasters Merlis had, only a single stage mechanical supercharger, why B17 had a 10,000 ft service ceiling advantage over the Lancaster !!!

[@Lord_of_The_World]

Gentleman really explained it well how these engines worked

[@MilitaryArmamentsCompany]

Thankyou for the kind words. Glad you enjoyed the video. Please check out the rest of our B-17 series.

[@JimErvin-d2i]

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.

[@MilitaryArmamentsCompany]

Absolutely. Brave men. Thanks for watching.

[@edwardcarberry1095]

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.

[@MilitaryArmamentsCompany]

Absolutely.

[@calvinnickel9995]

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.

[@MilitaryArmamentsCompany]

Great feedback, excellent information.

[@scottyb68]

So with the extensive work done on the Belle could it fly again? Or was it just made to look pretty? I understand it's historical value, but birds are meant to fly.

[@MilitaryArmamentsCompany]

Funny you should ask that. In a later episode I asked the restoration team that very question! Along with the condition of the Memphis Belle Wing Spar in relation to the 2023 Wing Spar AD from the FAA.

[@scottyb68]

@@MilitaryArmamentsCompany I'll check it out. 👍🏻

[@kkuenzel56]

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.

[@MilitaryArmamentsCompany]

She sure is! There are 3 "Memphis Belles" out there. This one being the real deal and the legend. Then there were 2 painted up for the 1990 Memphis Belle film. Nose art is slightly different. You saw one of those in UK, also known as "Sally B". The other is "the movie Memphis Belle." Currently with Palm Springs Air Museum in California.

[@walterbriggs272]

As a truck diesel mechanic, everything said is true. Which is why trucks have turbochargers on every engine. Old model engines from 40 years ago had a supercharger sitting on top of the intake chamber, but it wasn’t efficient and robbed power from the engine, turbos don’t rob power, they are driven by exhaust flow, and are necessary to drive in mountainous terrain, like Colorado, Wyoming etc. in recent years the “green” federal regulatorys mandated DEF after treatment systems to lower carbon emissions and completely ruined, in my opinion, the advances manufacturers had made prior to that erroneous decision. Companies research was on the brink of 10 mpg as a standard for trucks, which was phenomenal, unheard of prior . When the DEF mandate was finalized this killed any effort to improve efficiency, and research was ended for at least 10 years.

[@MilitaryArmamentsCompany]

Welcome Brother! You are speaking our language. If you look at our normal content outside aircraft there is a lot on tank diesel engines. The big continental AVDS 1790 engine is coming in depth soon! Diesel is the only way. Fun fact, did you know there is a diesel radial aircraft engine?

[@garethbarry3825]

The back pressure on the exhaust from a turbo does rob some power. Granted, less than the resistance on the crank from mechanically driven supercharger, but it does still rob power. There are naca reports from the prewar period that compare the two.

[@dpeasehead]

@@garethbarry3825 Nothing is free in powerplant world.

[@oldtugs]

DEF doesn't reduce carbon emissions, it reduces NOx, a much more powerful greenhouse gas. A particulate filter captured the soot that foul the air and leads to lung disease. The increase in fuel efficiency you mentioned was gained by increasing combustion temperatures which greatly increase NOx production.

[@steve1978ger]

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

[@gwcstudio]

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

[@bingosunnoon9341]

The supercharger was gear driven,

[@ronmeidlinger249]

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.

[@MilitaryArmamentsCompany]

HA! Best description i have ever heard.

[@andrerousseau5730]

Possible reason for absence of H-S decals: wartime secrecy to conceal manufacturing plant location.

[@marvthedog1972]

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.

[@MilitaryArmamentsCompany]

Absolutely! We have done 909 and Ye Olde Pub. Check out our Bomber Camp video to see modern B-17s today dropping bombs and working guns.

[@madmanmechanic8847]

Its too bad they restore it I would of left it original with all the bruises scratched up paint and dents I dont know why they have to do this to historical planes the same with Nolagay that dropped the bomb they went in and restored it too people suck ! Why cant they just leave shit alone

[@MilitaryArmamentsCompany]

If that logic is applied, the younger generation will be given no reason to care about the item, more importantly it's story. Additionally leaving items like these as they are and the structure will ultimately fail to where there is nothing left or any restoration will be not be financially achievable, condemning the equipment to destruction. Preservation of history is the main and most important mission. The plane that did the Hiroshima mission is called Enola Gay.

[@kylekeller9371]

Well said ​@@MilitaryArmamentsCompany

[@youtuuba]

madmanmechanic, you ask questions that would have been so easy for you to answer if you had done the slightest amount of effort simply looking these things up. You are also ignorant this this aircraft's history. It is not like it came off its last mission and straight to this museum. It had a hard post-war life; it was used as a combat training aircraft based on Florida and subjected to hard treatment and corrosive atmosphere, then it went to Oklahoma where it sat outdoors awaiting scrapping. Then the city of Memphis 'bought' it and it sat in a park (exposed to the elements) in Memphis, its metal rotting away in the weather and being badly vandalized over the decades. Its condition was by then horrible, and nowhere near the way it looked when in service or after a combat mission. The National Museum of the United States Air Force re-possessed it (they have the rights to do so for any former Air Force aircraft), and spent a lot of time and money doing a thorough restoration before putting it on display. Nobody in their right mind would say that it should have been displayed in the museum in its deplorable post-Memphis condition. And before you say anything about 'why were taxpayer funds used for this restoration', they were not. While the Air Force gives historically significant aircraft to the museum for preservation and public display, the museum and its restorations is funded by people like me who make donations.

[@daleeasternbrat816]

I restore Antique Engines. Automotive, Generator and Industrial. Sometimes I Start with a piece of equipment that, Sometimes, looks like a Titanic Artifact. I End up With an accurate and nice looking piece of Operational Equipment that is a proper representation of what the Generator, Automotive or Marine Engine appeared and functioned as when New/In Service. Leaving it to Rot....... Would make a guy like me God Nuts! Ahhhhh. A Packard Straight 8....... Some of this restored equipment gets used every day or activated in emergencies when heavy duty reliability and consistent operation is a must. Note, the DC-3 is operated in every kind of harsh, demanding, unforgiving environment on this Planet, Every Single Day. Those are the exact same engines that power B-17s. Those engines Get Up and Go to Work in the toughest places on Earth. In 2024. The airplane has a record of being one of the most Reliable, Safe aircraft in existence. And, people Make Money Operating Them. Every single day. SINCE 1936. Not Restoring Historic Equipment Is Not a Crime. But it would be a Shame!

[@WindsEternal]

Agreed! All-original but functional, as it would be back in the day, is the way to go, I think.