WW2 engines, BMW 801 vs. Soviet ASh-82

33:39 Russian manual translates as follows: “While flying under 1500-2000m you can activate high power mode by pushing the throttle and the prop pitch lever to their foremost positions. The revs should stay at 2500 RPM, with boost being 1200mm of mercury. This mode can be used for no more than 15 minutes in one go. This high boost mode (1200 vs normal 1000mm of mercury) will allow the plane to go 30-35kmh faster. Typically, this mode can only be used after first 10 hours of motor time.” Second page: “80. At the second gear of supercharger the use of boost higher than 1000mm is forbidden due to detonation risks. 81. Engage the second gear of the supercharger at altitudes greater than 4000-4500m 82. Watch the gauges to avoid cylinder heads getting hotter than 240 degrees celsius and the incoming oil getting hotter than 85 degrees celsius” Great video, thank you Greg

I have a degree in combustion engine technology from Munich Technical University, been fascinated with WW2 aircraft engines as long as I can remember and yet I learn something new every time Greg uploads a video. Keep up the great work!

I have a full set of engine manuals from Buick for the P&W R1830s used in the B-24. My Grandpa took them home after the war and gave them to me in the 70s. The engine manuals are leather bound and are a work of art. the rebuild manuals are ring binders. Someday i will donate these to a museum probably.

The quality of this channel is mindboggling! Love the calm low voice as well. Absoulte joy to be an audience

I remember as a child, and I am 75 years old, that all but the newest automobiles were followed down the road by clouds of blue smoke. They all burned oil. Then, seemingly overnight, this changed. New ring materials and coatings came to the market. I’m guessing that as always these advances first came to aero engines thus explaining the change from four ring to three ring pistons. The extra ring was just an attempt to maintain compression longer when poor ring materials were used.

Thanks very much for this video. La-5F and La-5FN are two forgotten Soviet fighters that really were great performers, their wing configuration is pretty interesting too.

In 2000, I went to the Hannover Fair, bought the most expensive ticket so I could be there all day, as I was in the line, looked to my left, and saw an airplane on a elevated stand, A Hansa jet with forward swept wings I read Fluzeug Museum, any plan I had for that day dropped on the spot, walked that way, paid my fare, and had an empty museum for myself, what a joy! Walked about and a staff member asked me if I had any questions, delighted, I started asking a few in my broken English, the gentleman said, “please wait here” and went away, a few minutes later the museum director was walking with me answering all my questions, and somehow amused that a South American was so interested in airplanes, this was by FAR the best museum experience in my life. We naturally stopped at the FW190 A series, and the very fist feature it called my attention was the BMW 801 engine, it had an enamel logo in the bottom front cylinder! He explained it was recently completed, told me several stories as to how he found parts here and there, next to it was another 801 engine in a stand, He told me when the Soviets were taking anything of value right after the end of the war, this particular engine was in a cart pulled by oxen, something startled them while on a hill, the cart tilted, and the engine fell off and rolled down the hill and into a ditch, where it stayed a few decades, I could touch and examine the engine, what a moment … indescribable how every systems , tubes and rods occupy every single crevasse and available space within its volume, a memorable day indeed in my life to get to see engineering marvels after 20 yrs reading about it. A year later I went to the Smithsonian hangar at Dulles airport, and saw another FW190 in a recently open wing sponsored by Ford, the guide told the group he was addressing that this particular FW190 was restored to a 100% condition, in that moment I became that smart ass guy who told out loud “no, it is not, it’s missing the BMW logo in the cylinder #1, right at the bottom” and pointed with my finger. Years had passed, and every now and then I remember how unexpected fate took me to see my favourite airplane and engine in different places while not looking for it. Thank you Greg.

Thanks Greg. One thing that is enjoyable about your videos is the quality of the comments. You have a lot of intelligent, knowledgeable people coming here because of the intricate information being conveyed - and that is refreshing. One sad aspect of life in the USA - is that with the cut backs to High School Education and the change in the nature of automobile power plants future generations may not have the hands on practical experience we had growing up. It was common place here for teenage boys to take Auto Shop as a class in High School - and then the older engines that were not so computer controlled could be worked on by any one with an interest. In some communities such classes as Auto Shop and Music - were dropped because of a lack of funding. For me - having rebuilt engines and changed the rings - I could readily understand the discussions about them. I remember me and my brother in law rebuilding the engine on a Fiat where the cylinders were not all the same size - and so - having bought all the same size rings - for one of the cylinders - we could not get the piston back in with the new rings on it ... and had to buy some different sized rings ... In my generation - working on cars was just something that (almost) every young man did. Now ... because of insurance rates - there are young men who don't drive because they can't afford the insurance - and have their girl friends drive them about. My point about that historically was that during WWII - one of the advantages the Americans had - in fielding a military that had almost no animal transport - was all those young men who had grown up working on their or their buddies old Model T's and such that had been handed down to them. Because of that - you had a lot more young men with basic mechanical experience who were easier to train - but - you also had more than that. A lot of the crews of vehicles - would know how to fix them at least on a basic level and were not as dependent on Motor Vehicle Maintenance to do it . All of which would translate into more vehicles on the road and not in the shop. I don't know how all this will really translate into the capabilities of young men and the military in the future but I am concerned about it. .

Spoiled us again! I really appreciate looks at eastern front and pacific technologies as the wider audience might not even know the la5-5fn! BZ

My guess is that the transition from 3 to 2 compression rings was related to the introduction of chrome plated upper rings. Chrome rings improved sealing and dramatically improved ring life, so that engine designers realized they could switch to 2 compression rings and reduce drag while still maintaining good performance over the life of the engine.

Greg, since you weighed in on the overall mediocre quality of the Wright R-2600, and its unreliability (presumably just early till the kinks were ironed out) I think you might be interested in my father's perspective on Wright vs. P&W radials from his AAF/USAF career as a flight engineer at the end of WWII on C-47s through to his pilot days flying MANY radial-powered multi-engine aircraft from the early 50s through to his retirement in 1971. These included AT-6s, B-25s, C-45s, C-46s, C-47s, KB-29s, and KB-50s. (His last tour was flying C-141A's in 1969-71). Basically, he thought Wright engines were garbage compared to P&W engines. He considered them notable for short periods of serviceability between overhauls, often a fraction of P&W engines, and general unreliability. For the B-29's R-3350, he shocked me once by commenting that the engine only had a service life of about 100 hours between major overhauls, and when you got a B-29 with high hours on the engines, watch out! He described one incident in which a B-29 engine started to overheat so much that the cowling started to glow red and then a cylinder head blew off the barrel and exploded up right through the cowling! (Which isn't to say the R-4360s were fireproof. My father lost a close friend in a KB-50 when an engine caught fire and he stayed in the cockpit too late to save himself while everyone else bailed out. Anyway, my father was adamant that P&W made superior engines. Period. My personal comment is that by a twist of fate I worked as a corporate lawyer in the Curtiss-Wright Law Dept. from 1981 to 2001. When I started the Corp. HQ was in a huge, former R-3350 plant located in Wood-Ridge, NJ. Many areas of the plant had changed little from the WWII era. The corp. culture there was "not the best," and the history of the plant from the "glory days" of WWII wasn't the best, either. See "Building the B-29 (Smithsonian History of Aviation and Spaceflight) (1995, by VANDER MEULEN JACOB) which has a great chapter on the R-3350 and the Wood-Ridge plant in particular. Having said all this, there is one Wright engine that made a major contribution to WWII, and that might be worth a "review" by you to discuss why it was successful. I'd love to hear your thoughts about the R-1820.

I think the main reason behind the drop in number of rings over the years is (among others), as you said, friction. Actually what happens over the years is that, in the quest for higher specific power outputs, engines increase their working rpm range and friction increases exponentially with speed. So the friction losses that are acceptable at one engine speed, become unacceptable at, say, double that engine speed. Also, at higer engine speeds, the loss of compression through ring blowby is less. So a high number of rings is now no longer required. More years go by... and now fuel economy becomes a thing, so now you have even less rings than before... and then anti-friction coatings on the piston skirts, and then you go to no piston skirts at all.

Did not know that about the Packard Merlins. I'd imagine that finding hardware in the modern era to keep them running must be challenging. Interesting as always.

Loved it will rewatch multiple times.

We need a kickstarter "get Greg a good microphone"

Another great video. It is refreshing to have technical videos that are informative, not 10 minutes of fluff. Almost like mini grad school lectures. As a former USN submarine officer I really enjoy history not being dumbed down.

Thanks for another great video! If I remember correct the Chinese still manufactures a copy of the Ash.82 engine, and that engine is what usually powers the few airworthy FW190:s that still exists (except for Paul Allens, where they managed to restore the original BMW 801). Really looking forward to next video with the advanced engine management system (the Kommandogerät!). Would love to hear your view, as a pilot, on it's effect on pilot work load - especially during combat/dog fights.

In professional aviation and in engineering in the US, I've used exclusively Celsius. Too many people think the US doesn't know how to use metric. In my engineering job we also seamlessly work in imperial and metric units. Units of measure are just a matter of preference and perspective. the units used to measure something has no bearing on how high quality the end product is.

Thanks for all your hard work in creating content and for posting it on here free of charge. I will never understand how anyone dislike content such as this. Another informative episode.

German native speaker here and I've been interested in WW2 aviation since I was a kid .... but trying to read that excerpt from the 190 manual explaining the C3-system kinda made my head spin. Talk about engineers needing to polish their communication skills. And I'm not sure this is due to the period the text was written in - I'm pretty sure you'd still find technical manuals to this day that would sound very similar in tone. This is almost like something out of a sketch making fun of what we call "Fachchinesisch" - meaning technical jargon or, more literally "professional Chinese". :D