Allison V-1710 - A Liquid-Cooled American WWII Warhorse

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In this video, we take a look at the developmental history of the Allison 1710 series of engines. Covering the inception of the Allison engine company and the many design iterations of the 1710 throughout the war. The most notable features of this engine were the combustion chamber design, the strong components, and the potential for turbo compounding technology.
#aviationhistory #wwiihistory #engineering

[@michaelmagill189]

Finally, someone who puts out the interesting technical info without posing as a post graduate engineering professor. I am a techno geek but I am mathematically lazy. I get bored quickly when the algebra starts. Keep doing what you're doing and I'll keep watching

[@johntindell551]

Me too...as soon as the algebra starts I'm done 😃

[@patchthesinclair5896]

Mathematical laziness creates great guestimators. I believe in it!

[@pyro1047]

I love Greg's Planes and Automobiles, but when he starts pulling out the line graphs and comparing Horse power, boost and manifold pressure, climb rate, altitude performance, Turbocharger vs Supercharger, etc... My eyes just kinda glaze over and I just nod and listen.

[@AmazingBilldo]

@@pyro1047 I LOL'd hard at this, even sympathetic tho I understand the math

[@bradschoeck1526]

Perfectly stated!

[@pimpompoom93726]

In retrospect, Allison should have parallel path'd Superchargers and Turbochargers on the V-1710 engine. Banking everything on a developing technology-turbocharging-was not sound strategy. I recognize their development was being funded by AAC during the Great Depression years and they probably couldn't afford the second path, but what might have been had they that additional funding? The cost of tooling up to produce the Merlin under license was probably way more that what would have been needed to develop a two-stage supercharged version of the 1710. A similar story with the 'Liberty' aircraft engines from WW1 compared to the Rolls-Royce Eagle series V-12's, America brought a great design to the table, but too late to impact the course of the War. Great video by the way, as a recently retired Engineer with 47 years in Auto industry powertrains, I really enjoy this stuff! A video on the Liberty Engine would REALLY be awesome, I've read a post-war technical report by the chief designer which was absolutely brilliant. SUBSCRIBED.

[@edwardpate6128]

The Allison was a VERY rugged engine and its use in aircraft like the P-40 and P-39 showed it could be significantly overboosted up to 70+ inches of manifold pressure with its single stage supercharger. I was always a great low and medium altitude engine and a shame it didn't have a better two stage two speed supercharger. In the P-38 with the addition of the turbo-supercharger it really shined!

[@wlewisiii]

This. I have a letter from a US General claiming he personally pushed a P-40E to 75" on a regular basis. The engineers at Allison hated this because when they changed the supercharger ratios in later engines, they started blowing up if pushed that hard.

[@AlanRoehrich9651]

The Allison was tested for HOURS at 80" of manifold pressure and 3,200 RPM. It easily passed the test. Repeatedly. The USAAF however hated the idea, and refused to approve the settings. However, units receiving 150 octane fuel routinely rigged the P-38 Allisons to run those settings in War Emergency Power.

[@jacktattis]

Great engine down low and RAF Mustang Is were still fighting in April 45 Those turbo supers were too large and added too much weight . The Mustang I was 10 times better than the P38 on low low Ops.

[@basiltaylor8910]

This is the engine Trans Canada Air Lines should have chosen to power their Canadair C-4M North Stars, as you rightly stated the 1710 is reliable and bomb proof, ideal for intensive airline application . With a three speed two stage blower, Bendix fuel Injection, a 1710 engined C4M North Star burning regular airport 100/130 grade petrol would have superior performance at high altitude vital to avoid those vicious North Atlantic storms.

[@patrickchase5614]

@@jacktattis The P-38 was designed as a pure interceptor. It wasn't meant for "low low ops". The turbosupersharged fighter that was really good "down and dirty" was the Thunderbolt.

[@johnfleming7879]

My dad was a Navy aircraft mechanic in WW II who loved the Allison- he was also put into the program to develop components of the A-Bomb at Oak Ridge, so he was a pretty sharp mechanic- The Allison did power one Salt Flats racer that broke a bunch of speed records after the War.

[@dennisford2000]

Green Monster

[@Mejrfrog]

Absolutely love what you’re doing here. I’ve been wanting a channel so badly to talk about propulsion of these interwar and WWII fighters. I know the KZbin algorithm prioritizes shorter videos but please keep them as long and as detailed as possible. Your hard work is very much appreciated sir

[@jimb4090]

I've got both the Information Guide, TO 30-5A-1 and Air Depot Progressive Overhaul Manual for this engine. They were in my Dad's attic since the end of WW2 and are in almost perfect condition except for some slight cover tears. He was a flight engineer and mechanic on several different aircraft so have several other engine and aircraft manuals as well. Well done video...

[@chickenfishhybrid44]

Thats awesome. Preserve those things.

[@ATomRileyA]

That is a pretty cool find, Might be good to scan them in and makes some pdfs of them so people can look at them in the future.

[@jimb4090]

@@ATomRileyA I could certainly do that as I have a monster of an HP 9500 multifunction but that would mean chopping the binding off to get flat pages. Think I need to keep them in the original..😎. Cheers.

[@Silverhks]

Yeah, I wouldn't break the bindings to scan them. I believe there is a technique to scan old books that doesn't damage them but I've only heard about it in passing. It might be wishful thinking for all I know

[@thiswillprobhrt]

@@jimb4090 nowadays a phone camera would certainly suffice. No damage to binding required.

[@JC-gw3yo]

It good to hear how good the Allison engine actually was... A few more years and the Allison would have been totally perfected

[@warfarenotwarfair5655]

Of course it was fantastic. The United States produced thousands and thousands of them. We are not like Europeans tolerating crap designs because your government said so.

[@glennoswald5928]

@@warfarenotwarfair5655 So said the F-35

[@wilburfinnigan2142]

@@warfarenotwarfair5655 65,000 Allison engines built !! !

[@warfarenotwarfair5655]

@@glennoswald5928 The F-35A is the new NATO fighter and is more advanced than any other multi-role fighter in the world. This became obvious in late 2015.

[@warfarenotwarfair5655]

@@wilburfinnigan2142 Exactly, they were used even after the war. In fact there are still thousands of WW2 engines still being bought for smaller tug boats operating in my area. It's amazing really.

[@philipingram1667]

Excellent video - like the new format. War surplus engines were used in earthmoving equipment by LeTourneau due to lack of Diesel engine availability and cost. Keep up the good work.

[@danhammond8406]

Rebuilt a muskeg buggy with a differential out of a Chaffee tank made by them. Dated to the early 1970s with ww2 surplus tank parts

[@alancordwell9759]

I'm really enjoying this series of excellently researched and well presented videos. Keep it up! Best wishes from Sheffield in the UK :)

[@terrywallace5181]

I greatly enjoyed this video. It was great to hear a more detailed history of the engine.

[@default123default2]

You are really good at these engine videos. I'll watch them all. Amazing how they had 4 valve per cylinder and roller valve parts back then.

[@patjackson1657]

Thank you for this very informative, both mechanically and historically, video! I enjoyed it and learned quite a few things.

[@55Reever]

You answered a question I have had for years and that was about the high altitude under powered reputation of the 1710. Thank you.

[@SyphenHouse]

Keep up the vids! I can nerd out on these engines for days. Enjoyed seeing your bookshelf and had a chuckle that it parallels mine quite well. Cheers.

[@hadial-saadoon2114]

A fabulous engine that was castrated by the Army. The two-stage engine was unwieldy but the hydraulic coupling was quite advanced. Great video, and all of you Allison fans should check out the book "Vees For Victory", an incredibly detailed history of the V-1710.

[@andyharman3022]

I have it. It is the definitive book on the history of the Allison engine. Author Daniel Whitney also has a follow-up book on Allison engines.

[@bobsakamanos4469]

Great. Can you tell us when exactly did Allison produce the new intake manifolds? ... and if they were retrofitted to engines in the field?

[@monsieurcommissaire1628]

You've got a new fan and subscriber here. Excellent work you're doing. The power figures for the turbo compound engine are astonishing. I didn't how how how such a sysyem worked until your beautifully concise explanation.

[@kevatut23]

Enjoyable read on a fantastic engine, and it's development path. Thanks much. Time well spent.

[@georgegherghinescu]

Good stuff! Like the new format! Good luck growing the channel and getting the algorithm to show it to more people. You already have the production to a great level, the research is good, delivery is plesant and friendly, like especially the way clips are formed to be like a story with little details of the times and about the people behind also.. not just facts and numbers. Ps: great old school radio voice :D

[@shawnbeckmann1847]

A very enlightening video thank you for all the new information!

[@thomaslockard9686]

Nice video, the Allison has always been the described as a dog by the uninformed. Glad you mentioned the Allison Engineering bearings which were its real bread and butter before the war. A little mentioned note about the 1710 was it passed the 100% power for 100 hours requirement that the Army specified, which the RR and RR/Packard were never subject to. And finally, the Allison is always compared to the later Merlin Mk XX engine with it 2 speed charger. Thanks for an interesting vid.

[@wilburfinnigan2142]

That is NOT the two stage version, RR use three different superchargers, a single stage up to the 20 series, the 20 to 50 series got a second SPEED, and the 60series got the drooled and slobbered over 2 stage 2 speed supercharger !!

[@DB.scale.models]

The RR tested there engines at full power for 24 hours, the knock down and checked for ware, and little ware but not measurable.

[@bobsakamanos4469]

The Allison engines had a host of problems, especially the intake manifold that caused detonation. The G version was finally well strengthened, but Allison never made a reliable high altitude V-12.

[@chickenfishhybrid44]

Well I'm sure alot of it has to do with the fact that there was a fair bit of surplus Allsions after the war and they were used in various applications such as tractor pull rigs and boat racing.. Theres a badass hydroplane that's been coming to the race in my town for the past like 10 years or more with a twin turbo Allison and he's the only one in the Unlimited class that's not running a turbine engine which has been the standard for 25+ years. He often gives the turbine boats a run for their money and has even won the event here. Then there's of course the vintage hydroplanes that run and they almost all are running Allisons.

[@dunruden9720]

alot ???

[@jselectronics8215]

I'm 75, grew up in Washington State, watched the hydroplanes on TV. There was always some team on limited funds trying to keep their Allison going.

[@chickenfishhybrid44]

@@jselectronics8215 Yep, I'm in WA too.

[@jselectronics8215]

@@chickenfishhybrid44 I remember Miss Thriftway was on a trailer, being displayed at the Thriftway store in Port Angeles. Must have been 1956. :)

[@danwolf307]

E.J. Potter ran these engines in pulling tractors and beat everyone for years. 4 blown hemis doesn't equal 1 Allison.

[@peteacher52]

Thank you! You scuttled some assumptions I nurtured based on hearsay about the Allison being under-developed because of political considerations between GB and the USA. Later of course, Allison became the masters of large turboprops in planes like the Electra, Orion and Hercules. One felt very safe in an Allison powered Electra.

[@wilburfinnigan2142]

Interesting that Rolls Royce bought out the Allison engine co for these turboprop engines that RR did NOT have !!!!

[@jacktattis]

w@@wilburfinnigan2142 Source please Wilbur you have a habit of stretching the truth.

[@clarkstonguy1065]

This video nails it, fantastic job of covering the Allison story.

[@timohanlon3683]

Love the format. Am loving these new vids. Used to be so into aircraft. Good to be back

[@JimmySailor]

Went down a rabbit hole recently with the American M6 heavy tank which began development in May 1940. Being 57 tons it needed a decent engine and the committee of SAE engineers assigned to look into it selected the Wright 1820 to supply ~825 hp. What I don’t know is if they looked into the 1710, which would have been in production at the time. Later in the war the Merlin would be used in tanks quite successfully. What’s interesting about the 1710 in this application is that it was a GM product and GM also had Hydro-Matic transmissions. In theory a 1710 with a Hydro-Matic would have made one of the best tank engines of WW2 and potentially a viable power package for decades. What I’d love to know is if a 1710 was ever arranged like that, for use in heavy vehicles?

[@kenneth9874]

The army air corp was sold on turbo superchargers and the navy was sold on radial engines so Allison concentrated on what they could sell, namely turbo supercharged two stage systems

[@wilburfinnigan2142]

The navy used 2 stage mechanical superchargers on the PW R1830 and the PW R2800's

[@jacktattis]

@@wilburfinnigan2142 I believe so however they were NOT as efficient as the Merlin or Packard superchargers

[@jacktattis]

You cannot put on a system of pipes and a Turbo-Supercharger that weighed maybe a 1000lb and still expect that there would be no repercussions . Plane efficiency goes out the window

[@philflip1963]

The best presentation on the Alison engine I've seen. Well done!

[@SeanC1959]

Very informative video FD. You really know your engines and their history. I'm now a new sub. Cheers Sean

[@gutofuhr]

I enjoyed to know that you and a few watchers also knew the V1710 was incially intended to replace the german V12 Maybachs used in the Akron and Macon airships. Airship tech was widely used in airplanes and I like both types. The Crecy book is a dead giveaway of an airplane engine geek, that's cool! If you intend to do a video only about compound engines, don't forget the Napier Nomad, which you certainly know that was a 2-stroke diesel aero engine prototype - a complete alien in the scene, but an interesting one. Great video, keep doing them in any format you like best!

[@richardprice5978]

so why wasn't there more diesel's in ww2 air-anything? as the nazis could have benefitted from them as high quality airo fuels for them was a challenge plus making one fuel diesel is easier and things like tanker's 🐯/sub's could use it and later the foo fighter's ect

[@gutofuhr]

@@richardprice5978 I am not shure, but the germans had a series of Junkers Jumo 2-stroke diesels that were widely used in bombers during the war like the Jumo 205, mainly because 2-strokes have a weight to power ratio good enough for aviation, close to 1kW/kg but they were never high-power engines fit for use in fighter planes.

[@shermanhouse6880]

Enjoying your videos very much thank you for your research and detail please keep them coming

[@androidemulator6952]

I glad i'm not the only one who delights in intricacies of these legendary engines.

[@davidelliott5843]

Have you seen the RR Heritage book “Rolls-Royce and the Mustang”. There’s a huge level of detail on the Merlin the Mustang and things like turbo compounding. By the way RR struggled with oil pumps. Merlins basically threw con-rods until they realised the oil pump was not big enough to meet demand at high revs.

[@gingernutpreacher]

Wasn't it also a poor system? as it started it self due to centraful force and that makes sense why high rpm gave it greaf

[@basiltaylor8910]

Oh shit Stan and Ernie been sleeping on the job, not to be aware of the Merlin,s undersized oil circulation pump, talk about a bad hair day. Why this serious issue was not flagged up in test bench runs at 3,000 rpm or more is odd and at least disturbing on such an important engine. So early Roller Merlins kicked their feet out the bed(con rods bursting from the crankcase) that is bad, thought the magneto drive issue was bad but Merlins kicking their feet out the bed at full power, that is dire so Stan,s spent too much time propping up the bar down the 'Rat&Ferkin' pub.

[@gingernutpreacher]

@@basiltaylor8910 you're a strange man ( but I like it )

[@basiltaylor8910]

@@gingernutpreacher Thank you for the kind comment , i do not pull my punches,in the late 1930,s due constant parsimony by our stupid short sighted air ministry our aero engine industry was a bloody mess.

[@jacktattis]

@@basiltaylor8910 Source please verifiable

[@AugustusTitus]

Great soup-to-nuts review of the engine. Did not expect such detail.

[@paulevans3261]

Outstanding!! Please continue with this format!

[@gregjennings9442]

Bottom line is that the Merlin had a better supercharger because the AAC was fascinated with turbocharging.

[@bobsakamanos4469]

More appropriately, GM and GE were telling the USAAC/USAAF what they were going to use. The turbocharging system of the the P-47 and P-38 were monsterous and vulnerable to enemy fire from behind. Superchargers were well protected by contrast.

[@migram4190]

Fantastic analysis of the Allison! Thank you!

[@EverythingAutomotive13]

Thank You for your channel. Great Job!

[@300guy]

I wish you were able to touch on the late war/post war installation in the P/F 82 and whether all of these almost solved problems had been finally put behind it or not. Very good presentation. I am surprised someone during the war didn't "accidently" you got your chocolate in my peanut butter the 2nd stage system from the V1650 to the V1710 1st stage.

[@vagellan_8842]

Very entertaining, informative video! Thanks!

[@jimallen5366]

Great video. Your comments closely match what my father told me. He was working in the Allison test bed during the war.

[@michaelbooher339]

Excellent video. Longtime aircraft mechanic. Truly enjoyed it.

[@ikay2102]

Yes!!!! In plain English, gentlemen explained history that even 5 year old would cherish. Thanks for sharing your knowledge 🙏

[@yourgrandmasalzheimerpills1143]

The Allison weighed less, had fewer parts and complexity, ran higher Manifold pressures, smaller profile, and also had better build quality. It really was only drawn back by the lack of supercharger technology and turbocharging. I mean the p-38K (and D/J) models could easily sit at or above 45,000ft with the turbosupercharger configuration.

[@keithstudly6071]

I would add that the V-1710 was designed to be reversible unlike the Merlin, one of the reasons that the Merlin was never used in the P-38. While we are thinking about the P-38 a large amount of the trouble with them was on account of overly rich fuel mixtures and excessive intercooling resulting in poor fuel distribution between cylinders that resulted in plug fouling and detonation, depending on whether the cylinder was one that tended rich or one that tended lean.

[@douglasadams6024]

agree 100% the Allison had 4000 parts the Merlin had 11000!!!

[@GroovesAndLands]

110% The Merlin was super neat, of course - but it was designed by British artisans to be built by artisans. The Allison was designed to be simpler and easier to build on more-automated assembly lines...the 'Merican way.

[@jacktattis]

No the P38 could not sit above 45000ft WW2Aircraft Performance gave it 40000ft Max That Turbo/super installation was not as efficient as the Merlin supercharger

[@yourgrandmasalzheimerpills1143]

@@jacktattis if it were pressurized, the p-38 and p-47 were capable of those altitudes. Watch Greg’s airplanes on turbo supercharging in US warplanes. Theoretically the P-38K and the Ta-152H were more efficient than the Merlin 2 stage supercharger. In fact the Junkers 86 operated over Britain at 50,000ft while carrying bomb loads.

[@MichaelVLang]

Deep dive explanations of these monsters needs to be done, great vid. The engineering done that led to the launch of Apollo in this era is as high tech and clever as any modern engineering. It seems so long ago.

[@williamstel9330]

The Allison engine was in several drag race cars one I remember was called Big Al 2 I did something like 9 seconds at 160 something because tires and clutches weren't developed yet. And I remember always being impressed with those powerful engines and asking my dad if they ever put one in a big truck and he thought that someone had but it tore up the transmissions.

[@phlodel]

My friend's grandfather said he used to drive a truck with an Allison engine. It was used to haul scrap metal over the Grapevine in California. He said it could run up the hill with a heavy load without slowing but it destroyed driveshafts.

[@scoot77777]

Very well done! Nice work 🫡🛩✅✈️😊🇺🇸🇺🇸

[@topturretgunner]

Really well done and informative. Thank you.

[@victorcontreras9138]

I love your optimism in this engine that I first saw on display at Dover AFB museum. "Keep it American" is what I've always said! Give it a chance⚠️

[@shawnsan9]

Well done. Thank you. I actually understood almost all of that.

[@raulduke6105]

My Pops was a Allison factory trained mechanic. Thanks! Miss him.

[@robwhite3241]

During Korea my grandfather was stationed in Japan as a stockyard manager. Somehow they managed to loose one of these engine and well they all got into a bit of hot water so they said It must have been stolen. They sent out a search crew but nothing was ever found, he thinks its still at the bottom of the ocean. lol

[@charlesdavis7940]

Super interesting video. Very well done. Thank you.

[@RichardGoth]

Great video. Love the new format

[@Thunderous117]

Great video, I think one thing worth adding is that while in hindsight we often remember the p38 taking a background role in Europe to the p51, it is well worth considering that before the p51 really came into its own with the merlin equipped p51b and p51c in late 1943 USAAF commanders were clamoring for as many p38s as they could possibly get. The p38 bore the brunt at perhaps the peak of the luftwaffes strength in well trained pilots, and before the fuel shortages and impact of the bombing on parts availability and quality were felt as the allied war effort strangled nazi germany. The p51 with the merlin just changed the game in having a fighter that could go the distance with the heavies at a far cheaper per plane price than the p38. Anywho, I really liked the video and will be subscribing, you clearly put a lot of effort into making this fantastically nuanced video on this fascinating topic, well done.

[@CharlesStearman]

I've read that one reason for the P38 being withdrawn from the bomber escort role in Europe was its relatively low critical Mach number, which limited its maximum dive speed at altitude to less than that of single engined types.

[@gandalfgreyhame3425]

Actually, the P38 was withdrawn because it had a huge number of issues with flying at the high altitudes of the European air war - a report by Doolittle stated that there was a high loss rate of the P38s due to engine failure, having to do with uneven fuel distribution amongst the pistons so that some got an overly rich fuel-air mixture and others got a lean fuel-air mix and so would suffer problems with detonation and premature crankrod failures (Doolittle explicitly blamed the design of the air-fuel manifold of the Allison V1710s) . The tetraethyl lead added to the British fuel also tended to separate at the cold altitudes, which further worsened the problems with detonation. This is all documented in the book: "P-51 Mustang: Development of the Long-Range Escort Fighter" by Paul A Ludwig

[@bobsakamanos4469]

@@gandalfgreyhame3425 the Allison intake manifold was one of many issues with the P-38. GM was slow to authorize R&D funds to allow Allison to correct that, among other issues. Pilots called the engine the Allison time bomb. The P-38 airframe was also one of the worst for critical mach speed. Dive flaps solved the "mach tuck" and control lock up, but the max dive speed was still unacceptable above 20,000', so it never was a good high altitude fighter as the LW could just dive away.

[@pimpompoom93726]

@@bobsakamanos4469 P-38 had it's shortcomings, but it had the RANGE which was needed to escort bombers. Spitfire was useless as a bomber escort.

[@bobsakamanos4469]

@@pimpompoom93726 range yes, but what good was that if it couldn't operate at altitude with the bombers. A tragic error for both P-38 pilots and Bomber crews. It was a fine attack aircraft for ripping up LW on the ground though.

[@WPF465B]

Really excellent presentation, thank you

[@nickcosentino5368]

I had to listen to the turbo combining twice, that's brilliant.

[@wirksworthsrailway]

A great overview and very well poresented. By the way, I see the book on the Rolls-Royce Crecy over your shoulder: designed just a few miles form where I live!

[@PeteCourtier]

Great stuff👍 Really interesting and I like the new format. Is the RR Griffon next? Maybe a Bristol Centaurus👍

[@bwfvc7770]

Thanks for another very inciteful analysis.

[@user-df8it8bs7t]

Realy like new format. Looking forward for new vids!

[@joellamoureux7914]

Love these videos. I'm gonna put one of these in my chevy sonic. I'm going to sit in the trunk.

[@ceebee23]

fascinating story .... and great to actually see the face behind the voice!

[@grogon9614]

A mechanic for 40 years and I just learnt about turbo compounding, very interesting.

[@Cheka__]

Nice shout out to Greg's Airplanes and Automobiles. These videos remind me of his. He's all about getting into the technical details of WW2 aircraft engines.

[@mikedee8876]

Allison still carries a great name for quality and heavy duty performance....hope they never lose that reputation....

[@malcolmsmith650]

The engine was actually smoother than the Merlin but where the Merlin beat it was in supercharging. It was the Merlin supercharger which allowed it to excellent at height.

[@patrickchase5614]

Specifically Rolls' ability to package a solid 2-stage unit onto a single shaft, and fit into basically the same space as the original single-stage unit. Two-stage supercharging was nothing new - the USN had it in the Wildcat and Corsair long before the Merlin was upgraded to have it, but they both had their second stages in bulky external units with separate shafts and gearing. The Merlin's real innovation was in getting decent performance out of a compact single-spool unit.

[@princesofthepower3690]

@@patrickchase5614Merlin 60 had 2-stage chargers as far back as summer 40’. Well before the Wildcat first saw combat with a 2-stage supercharger.

[@patrickchase5614]

@@princesofthepower3690 Nonsense. The F4F Wildcat first flew in 1937 and became operational (with two-stage supercharging) in 1940. The very first 2-stage Merlin was bench-run in April 1941 and deployed in 1942 (so after Wildcat "first saw combat", though that's irrelevant to development timeline in any case). Merlin was late on the scene with 2-stage supercharging. What made it unique and brilliant was that it did it in a compact, single-shaft form factor as opposed to the bulky arrangement that Wildcat had. Merlin did gain two _speed_ supercharging in 1940. Might that be the source of your confusion? Note that that was also late relative to others though.

[@bobsakamanos4469]

the Allison was smooth and cruised nicely at lower RPM, using crank counterweights, but it had a horribly designed intake manifold (that caused detonation), among other things. The overboosting of early P-40s also caused a lot of engine fires and failures in the slow P-40's, but that was an acceptable risk to Sqn pilots up against superior fighters.

[@bradschoeck1526]

This channel has become my favorite KZbin channel. It’s amazing to discover all these complex technical issues that were figured out 70+ years ago. The Second World War was the pinnacle of technological achievement in my mind, though obviously many could successfully argue that, but I would posture that much of the post war technological development was cheating by using either jet propulsion and later, digital control systems. Yes the planes were better post war, but jets bore me. Nothing beats a good ol warbird with big ol air screw bolted onto a massive power plant that harnesses a bunch of explosions to make it fly. I wish I were born in an earlier era!

[@BTf337]

Great video - thanks!

[@jayfrank1913]

They were still using 1710s and Merlins in the piston-powered hydroplanes in the 80's that were raced at Seafair here in Seattle. The turbine hydros always won (Miss Budweiser, Miss Miller, etc...) by using the GE gas-turbines from Bell helicopters

[@tomnekuda3818]

I cannot believe the amount of work that went into the development of this engine to make it durable, dependable and possessing adequate horsepower. Whew!!

[@jeffbrooke4892]

Excellent, thanks!

[@aerotech1bob]

Great review of a great underrated engine

[@kevinjohnson8758]

Good info. Good pace.

[@mamulcahy]

Excellent video!

[@David-wk6md]

I have one in my '71 Ford, Pinto. I love it.

[@Redhand1949]

You are a nice complement to Greg's channel. I have subscribed. Please discuss "turbo compounding" in the context of the Wright R-3350, where I understand it was perfected in the 1950s in airliner service. I used to work for Curtiss-Wright (for real) beginning in the 1980s and some of the old-timers there discussed this configuration of the 3350. I never really understood the difference between a two-stage turbo-supercharged engine and "turbo-compounding."

[@bingosunnoon9341]

Turbo compound was never perfected. I worked in the TWA shop in KC and the old timers hated them.

[@EstorilEm]

@@bingosunnoon9341 Lol the good old PRTs, “parts recovery turbines” 🤣

[@andyharman3022]

I worked at John Deere Rotary Engine Division, which was bought out of Curtiss-Wright in 1984. I worked with some of the old Curtiss-Wright engineers that really KNEW the 3350 and were very sharp engine engineers in general. Did you know Charlie Jones, Davey Meyers, Dick Gigon, Augie Zoll, John Mack, and Ed Drewniany? I learned a lot from them.

[@arthurferreira1462]

I never worked and most likely will never work with engines. Yet, here i am binge watching greg's and dojo's and also trying to find a good yet simple enough explanation of what a turbocompound is.

[@oml81mm]

Excellent video and very well explained. The merlin engine had it's problems as well, often solved by testing to destruction, inspection and redesign. This resulted in an extremely strong and reliable engine which could easily cope with the power increases that came later. The main problem in the early days was with the supercharger but a scientist (not engineer) called Stanley Hooker solved that. His speciality was fluid dynamics, and it is said that anything that flows is a fluid, including air. Anyway he transformed what had been expensively and laboriously made into a good and reliable engine into something special. I should add that rwo other things helped a lot... high octane fuel and ethyline glycol, both from the USA!

[@ManiacRacing]

It's easy to forget, they didn't have the design tech for good compressors and turbo impellers, They were still working out how to actually make boost. And it's much different at altitude compared to car or truck use.

[@anthonylivelli5880]

excellent job great video

[@peterweller8583]

Nicely done good job.

[@ben3989]

I heard these 1710's every august in Seattle when the unlimited hydroplanes came to town. They were running Allisons and Merlins into the 80's before mostly shifting to large turboshaft turbine engines.

[@patchthesinclair5896]

I have a fantasy plane, it's a de Havilland Mosquito airframe built-in carbon fibre. In my fantasy I'm always looking for more power than the Merlins it was originally given. This is an interesting part of the dream!

[@williamstel9330]

Great job

[@aurorajones8481]

fantastic vid

[@SoloRenegade]

Allison had altitude issues overall, for points you addressed, but from a marketing standpoint, the engine was reliable, and was great for low altitude aircraft designs (Soviet Union?). And it did prove to be capable if someone could design a proper forced induction system for it.

[@jacktattis]

You are forgetting the RAF Mustang I, in action10 May 1942. One year before the P47. 2 years before the P51D and 2 months before the P38 in the MTO

[@SoloRenegade]

@@jacktattis good point. But the P-40 was flying the Allison in those theaters it even before that.

[@jacktattis]

@@SoloRenegade Yes indeed but the Mustang was the cream on the Cake

[@SoloRenegade]

@@jacktattis for sure

[@bobsakamanos4469]

The Allison had a number of problems, especially the intake manifold that was finally redesigned and deployed in 1944. Detonation and lead fouling was an ongoing problem during the war. Desert P-40s had engine fires and failures.

[@chris_hisss]

Good stuff. Would have liked to seen more design bluprints and how the engine changed over time, like coolant flow, cam changes, I am sure there were plenty of little twaks.

[@TheGreg6466]

13:39 That Aircuda was an awesome idea, it had two 37mm cannons! shame it didn't work well in practice.

[@jamesbaker7112]

Good stuff. Subscribed.

[@vagellan_8842]

@20:59 after each spec quoted I literally yelled out, "Wow! Jeez! Wow!"

[@jamesb.9155]

Fascinating that there were the 3 main-stay high output V-12 engines between the Brits, Americans and the Germans especially for their fighter aircraft. I have been to the Evergreen Flight Museum here in Oregon to see the Pratt & Whitney R4360 28 cylinder water cooled radial engines which are still fitted on the Hughs 'Spruce Goose'. It is very amazing how the jet engine simplified & improved everything so quickly.

[@jamestregler1584]

Great talk, thanks 👍

[@stevenborham1584]

I see you have the Crecy book behind you. That engine and the 2-stroke X-16 engine would make for a real interesting vid on what T-compounding could have achieved.

[@KW-ei3pi]

Excellent video, as always. Your speaking ability is excellent, and the logical development in presenting the material is also excellent. Off topic but related, I am always amazed at the shear volume of technical and engineering development in the early part of the 20th century, especially in the 1930's. No doubt you have noticed this in the research of your videos. Perhaps it could be a subject of a video, if you can pin down exactly why this was the case. Regards.

[@n3307v]

Very cool video.

[@mopartron3030]

Interesting mention towards the end regarding squish/quench not being properly utilized for increased anti-knock capability. From my experience with high-performance automotive engines, for squish to be used effectively there must be a portion of the piston head's surface that comes within roughly .045" or less of the combustion chamber surface when the piston is at TDC. My guess is this was hard to implement without a complex piston dome/dish shape because if it was simply flat then the volume at TDC would have been small and compression ratio likely would have been much too high to be suitable for the intended manifold pressures. Just a thought, makes me want to read that Horsepower Race book even more now...

[@ronjon7942]

Nice work.

[@9traktor]

One of the best aero engines ever!

[@BARelement]

ANOTHER BANGER ALERT! New video aye :3

[@j.edward4379]

It seems i hear more about the war time Rolls-Royce engines than the Allisons. Good video. The first time i heard these engines were in Unlimited Hydroplanes that raced in my hometown. I tell you there is no comparison when you hear 5 or 6 of these engines racing to the start line. You feel them.

[@FiveCentsPlease]

[e-mail]4379 From the 1950s to the 1970s the boat racers blew up and scrapped those engines by the hundreds unfortunately. I know Hydroplanes want to return to piston racing and rather than using any more of these WW2 engines, I'm glad to see that Aardema Development is designing a new V12 series in the spirit of the Allison that they want to use in boat racing. Guess we can see where this effort goes. kzbin.info70vKqTM1Bro

[@thesep1967]

Extremely reliable engine, perfect for lew-level air-work. The British used their P-51As (Mustang I and II) until 1945 in the army cooperation mode. At those heights it could outrun anything the Germans had. The Allison also had good behaviour at low revs (a perennial problem with the Merlin), perfect for long range missions at economic throttle settings. The Russkis loved their P-39s too and put them to good use in another low-level scenario.