Lost Legends of the Luftwaffe - Junkers Jumo 222

Discover how the Jumo 222, with its innovative design and impressive performance metrics, aimed to secure aerial superiority for the Luftwaffe. Yet, as the war progressed, shifting priorities and resource constraints led to its ultimate downfall. Despite its potential, the Jumo 222 never reached mass production, overshadowed by the war's demands and the emergence of jet propulsion technology.

As we delve into the story of what could have been a game-changer in aerial combat. The Junkers Jumo 222's legacy is a testament to human ingenuity and the complexities of war, offering a glimpse into an alternate history where the skies might have looked very different. Today's video not only pays homage to the engineers behind the Jumo 222 but also prompts us to reflect on the countless "what ifs" of World War II.

[flightdojo]

I did say "anne-als" by the way, instead of "anals" but I can hear what some of you mean, it's easy to hear it either way, imo. Next time I'll be sure to be more anal in my quality control.

[ralfklonowski]

I am German, a mechanical engineer and aviation enthusiast and I work as a teacher at a technical vocational school. I love this video in so many ways. Masses of information I never heard of before, in-depth content and a clear, sober yet also entertaining presentation.
Bravo!!

[ArnoudvanOlst]

You tell it incredibly detailed without being boring. That's a rare quality.

[Stellaknot]

Love your content! Please keep up the great work!

[MattBorgardt]

Just found your channel and I am already binging...

[brealistic]

Don't throw shade on this very innovative engine. I have never seen anything like it. Great video topic.

[weeks]

Love the information-filled presentation and the non mainstream information! Great video! Good luck finding YouTube content offering in depth and obscure information like this! Good job!

[texasknight]

I visited the Deutsches Museum on the last day of a trip to Munich. But, I did not know it was divided into Air, Sea and Land...! We just wandered into the closest building which turned out to be Sea. Still amazing. But, wished we'd gone to Air.... ;)

[Big-Dawwg]

Very well done I might say, I've seen this JUMO 222 Film before, as our family has some of Hugo's 8mm Movies made in the 1920's and early 30's, keep up the good work....
BD in 😎

[tsegulin]

Huge shout out to Flight Dojo for this documentary! I've always been curious about the Jumo-222.

The British developed the radical high-power 24 cylinder Napier Sabre, the Americans developed their big Wright R-3350 and Pratt and Whitney R-2800 radials and all of them saw service, albeit with reliability and maintenance issues. Interestingly development of the Sabre and big American radials began in 1937, as did the Jumo-222 but it never saw wartime service yet the Allied engines did. Why did no large, high powered German piston aircraft engine ever see service? I saw the Jumo-222 at the Deutsches Museum, Munich decades ago. It had always been rather a mystery to me.

Certainly earlier in the war, there was a need for heavy bombers but a cascading series of management errors prevented it.
There was the decision to kill the Ju-89 and D-19 after Generalleutnant Wever's death, thanks both to the OKW's tunnel vision of the Luftwaffe as merely tactical air support for ground forces with no interest (or perhaps even understanding) of the value of strategic bombing, plus concerns over limited supplies of aluminium and other resources. Then there was the ridiculous dive bombing requirement Generalluftzeugmeister Udet imposed on the He-177A (followed by what Heinkel described in his book as Reichsmarschall Goering's refusal to allow him to end the systemic coupled engine fires with a 4 separate nacelle He-177B which might well have become a German version of the rebirth of the failed Avro Manchester as the successful Lancaster). All of this ended up virtually denying the Luftwaffe the heavy bombers it could have had and which might have made a big difference in the battle of the Atlantic and on the Eastern Front. By mid war, the whole bomber (and maybe the large, high power engine) issue had become moot as Germany had lost the initiative to take the offensive and instead needed fighters to defend itself from increasingly large Allied bombing raids.

I had always believed the Jumo-222 to have been an overly ambitious technical failure that ended up killing the bomber-B program and the FW-191. I expected that Junkers Motorenwerke had limited numbers of staff engineers and they were already over-extended in development and meeting hefty production targets for the Jumo-211 and later the Jumo-213 as well as the cutting edge Jumo 109-004 gas turbine program, plus there was development of other jets and even turboprops which ultimately only benefited the Soviets . I assumed there simply weren't enough remaining to adequately develop the Jumo-222.

This video appears to suggest otherwise.
As I understand your argument Flight Dojo, the Jumo-222 was a promising engine that overcame major engineering challenges and showed genuine prospects of success but whose development was compromised (once again) by the RLM, and changing political imperatives. Without looking at dimensions, I wonder if some version of the Jumo-222 could have been incorporated into existing fighter airframes? My gut feeling is that it would have been so big and heavy that like the Hawker Typhoon, Republic P-47, or Chance-Vought F4U a larger airframe would need to have been designed around it and by mid war there was no time or resources for that. Besides that might have further compromised the jet fighter programs. Anybody know for sure?

An interesting Jumo-222 feature was the 2 speed supercharger which appears to have been aligned along the engine axis, like the BMW-801 radial, not at right angles to it like the other Jumo and Daimler-Benz inline engines. I guess this must have been due to the hexagonal radial layout of this engine. Also I notice that the Jumo-222 E/F included a 2 speed, stage supercharger with a second stage driven by a fluid coupling like the DB-601, 605, 603 engines., the subject of much prewar research at DB yet something not seen in other production German aircraft engines. Stanley Hooker's 2 stage supercharger had hugely advanced high altitude performance of the later RR Merlin engines. I wonder if Werner von der Null's work was the basis of this?

A typical Jumo design feature at the time was the 2 inlet, 1 exhaust valve arrangement.
The 4 valve heads in the DB and RR engines seem to have been better and eventually the later Jumo-213 head was redesigned to take 2 exhaust valves. Anyone know why Jumo hung on to 3 valve cylinder heads for so long? Cost? Simplification?


Although she possessed so much engineering expertise, Germany was hamstrung by limitations on metals needed for high temperature and high tensile alloys plus issues with high octane equivalent fuels, yet remarkably managed to produce very competitive piston engines. The Jumo-222 might have played a considerable role in the war had it been available early enough.

Great video, thanks Flight Dojo.

[stevedrane]

Fascinating. . . I would not want to set the valve clearance up on the engine. . 🤣
Thank you for your time enlightening us. 👍

[Un_soldat]

I love seeing these videos being uploaded thank you!
I wonder what will you do once you run out of engines would you cover the guns on aircraft?

[K-Effect]

Excellent video, thank you for providing such high quality content

[guaporeturns]

You had me at "liquid cooled inline radial”

[stephend]

Okay. Who watched this video 13, 000 times and didn't hit the subscribe button?
It was you! All along!
I'm really a fan of other technical creators, but this is a pretty decent video, and I did need to know more about this powerplant. Coz I'm a guy. Nat. I really appreciate this video, sir. Thank you for keeping this history and this data alive, and it is well presented. What I could do (in my imagination) with a motor churning out 2.5 Kw @ 3, 200 rpm and 6.75 Okay. I'll hit that subscribe button and check you out.

[Nobody-ocqb]

Enjoy your videos, being an aviator (job), P/T engineer, engine builder and warbird enthusiast, I can be a real PITA on correctness! 🙂 IMHO your channel, along with Gregs airplanes and Dr Mark Felton's Productions, is one of few worthy of viewing. Well researched, produced and presented. On point and fact based. If only the likes of the once upon time watchable "History" TV channel paid half as much attention... So many channels are kid made, poorly produced, aimed very low, and loaded with hyperbole and inaccuracies. Not yours! Thanks for your efforts. SUBSCRIBED!

[hadtopicausername]

And then the jet engine decided to show up and go: "Hi, I'm going to make you completely obsolete!"

[hadial-saadoon]

Your recommendation of Calum's book has really opened up my interest in the subject. In the context of the 222, it still had a 3-valve combustion chamber. Added to this engineering faux pas
was the scarcity of strategic metals that inhibited the quality of their otherwise advanced engines. Great video, and thanks for the recommendation of the book.

[basilb]

Great video as always. Small hint - almost all photos of the Ju 288 show it with the Daimler Benz DB 610 engine and not with the Jumo 222.

[tonybarnes]

Well I know many engines have sodium cooled exhaust valves, and apparently that tech is still used today. But I've never heard of this technology used for intake valves! Something about the pressure of war, technology is pushed and many variations of already known principles are applied in different areas to try and get that "step ahead" improvement.