I had SPICA mechanical fuel injection on my late 70's ALFA Spider. It was completely alien to a young American boy.

My father was made redundant as a flight engineer in Australia 1962 and returned to the Netherlands. (He was in the Dutch resistance during the war.) At Fokker he bucked the very hierarchical system that was in place. His brother for example was a solid achiever but he hardly moved up since the war. My father was tasked with rust prevention in the F27 fuel tank. Apparently his work was quite good. When presented to the technical board his boss claimed my father's work as his own. I think he objected, was told to know his place, and the chap bounced off the window when punched. It was the first floor. He then on being sacked returned to Australia and flew with another airline. I bring this up as anecdote simply bc absence of truth is not just the failing of politicians, lawyers and real estate agents, in the technical world, prejudice, jealousy, deceit are as equally rampant. And Calum brings this up with his tweet on Beatrice Shilling twitter.com/CalumDouglas1/status/1650227982739427332

and guess-and-check too

@@alexander-lc4dr tons = lots in this context, tons is a mere word, not a unit of measure. I take it English is not your first language? Just like how fillet of fish is not the same as fillet on a machined part. They are spelled the same, pronounced vary differently though, and mean totally different things.

@@alexander-lc4dr "To say a 150 with 150 naturally aspirated horsepower has "tons" of climb performance over 10,000 feet agl isnt English, its rather unbelievable." then english isn't your native language, as this is a commonly used term in day-to-day conversation. "a video discussing non dimensional axes on compressor maps, instead of using "tons" you could have said "200 fpm"" not really, as I was flying the corridor for teh grand canyon with strict altitudes, and could only climb for a few moments before returning to altitude, so I don't know what it was getting exactly, but it was way more than a Cessna 172 at that altitude, at least 3-4x more. "tons" is an appropriate description, as the airplane was climbing far better than anyone would expect it to.

While I understand your defence of your commonly used aircraft, the engines in them are extensions of prewar designs and are indeed older than the VW beetle engine. A C172 is the most pedestrian of all the cessnas and my aircraft mechanic and aero sparkie Father refers to them as "VW Combi's with wings, with a lesser climb rate". Callum is talking about engines that put out 55 to 65 HP per litre above 20,000 feet. The lycoming and Continetals average 30 hp per litre on the ground and closer to 20 hp per litre at even 10,000 feet. The expression "tons" when used in common slang, infers the same as "Heaps" or "Bucket loads" etc, which no high wing cessna is close to. Expressions like "by the skin of its teeth" or "squeaked through" would probably be more appropriate. NOTE: C-172 listed as 700 feet per minute at sea level and 100 feet per minute at 13000 feet per minute. A Spitfire Mark V is listed as 2900 feet per minute at 13000 feet!

@@philkennedy8683 "A C172 is the most pedestrian of all the cessnas and my aircraft mechanic and aero sparkie Father refers to them as "VW Combi's with wings, with a lesser climb rate". " the fact you have no idea what a C150 or C140 is........clearly I'm not talking to an aviation expert. No VW engine is going to power a C172, I also own a VW powered airplane, and that engine with modifications only puts out 1/2 the HP of a C172 engine. " C-172 listed as 700 feet per minute at sea level and 100 feet per minute at 13000 feet per minute. A Spitfire Mark V is listed as 2900 feet per minute at 13000 feet!" this comparison has no relevance and proves nothing. wow. You clearly are talking out of your ass.

@@SoloRenegade I grew up around the airfield my Father worked at. I own a hangar and even have a 1946 Cessna 140 sititng there. A C172 engine, of 360 cubic inchs makes a measley 180 hp when in perfect condition and in perfect conditions. The 0-360 is fundimentally the same design as the prewar 0-145 and still only squeezes out 30 hp per litre. As a comparison the currently popular Rotax 912/915 series engines make 2000 TBO's with 100 hp per litre outputs. Calum's video is about performance engines for performance aircraft but you decide to get offended by him refering to your beloved Cessna's as asthmatic, without stopping to think that this man who is a highly qualified engineer and engine designer might know what he is talking about. By all means enjoy your cessna 140/150/172 or any other aircraft but please don't compare them to performance engines or aircraft

Yes you are wrong. Having a valve with low Nickel does not "instantly" make the engine knock, but when this valve inevitably does start eroding, (which can happen fairly fast, only a few hours is needed) several things happen, the valve head scales, these sharp edges glow and cause pre-ignition hotspots, the valve head also begins overheating because it starts not seating correctly and so the thermal transfer goes down, so the temperatures in the exhaust side of the chamber all go up. A mixture of detonation and pre-ignition then begins depending on the various circumstances/power levels used etc. You can read all the original reports yourself if you read my book, which quotes from them all and these translated reports on this issue begin on page 271.

@@CalumDouglas Ah, I've just seen the explanation in your other IMechE-video. Got your book some days ago, but will need several weeks to get through 🙂

I cant answer this definitively, but I would very much suspect not. There have been a few Spitfires "at" the races but they were not race-prepared, but just warplanes that flew the circuit. Which is sometimes quite a different thing entirely. I think the main issue is a serious lack of parts (remember lots of Allied engines like the Merlin were made long after the war ended for civil use so you have lots of "new old stock" parts kicking about even today, and things like the civil Merlin had substantial development effort put into them post war to really iron out all the bugs. German engines never had any of that, and they would need very significant work to put them in a position to do that, given their rarity the risks are I think judged far too high to race. Ignoring all practicalities, I think something like a highly tuned FW190 or maybe some of the things Heinkel had on the drawing board would be contenders.

@@CalumDouglas To complete the alternate history, the idea of racing against fully tuned Zeroes or their descendants comes to mind. Once again the defeated ran out of swords and swordsmen, it's no wonder there were so few airworthy examples after the war. Great work Callum, thank you.

@@CalumDouglas Calum, your homepage doesn't really have a mention of your second book. I didn't realize it was out until I did a search based on your mentioning it in the video. I'm going to see if my son has an ASME membership, and then order a copy. Thanks for some really interesting material. Good luck!

Because a single stage compressor (irrespective of whats driving it) of the period is limited to about 3.5:1 pressure ratio, which means the critical altitude (rated altitude) will always have a pretty moderate level. A two stage compressor will get you about 6:1 pressure ratio but will also consume several hundred horsepower to drive it, hence the attraction of using exhaust gas energy to do it.

@@CalumDouglas I see, thanks. Your book is excellent by the way. I'm reading through it right now.

@@CalumDouglas Hey Calum, may I ask another question. At 44:38 you say that Daimler-Benz used the variable inlet guide vanes on their compressors. But why would this be necessary if they had variable speed superchargers? Did the swirl throttle "add" efficiency in addition to the variable speed supercharger? Or was the swirl throttle only useful at low altitudes where the hydraulically-geared supercharger was limited by some minimum RPM due to maximum slip?

@@dogeness because the variable speed coupling is limited to about 33% slip otherwise the oil gets too hot. If you have BOTH IGV and variable speed couplings, you can extend your compressor by enlarging it so its a lot bigger in capacity than you would normally be able to stand at sea level without undue throttling losses on take-off, and then apply maximum slip AND very high pre-swirl on take off. Thus when you get to rated altitude with both of those set to zero, you will have a higher rated altitude AND manageable throttling losses at take off. There are also other factors at work but that's the very basic summary.

@@CalumDouglas very cool. Thanks calum

Why not just click 0:13:30 in the comment someone already made, so it skips it ? Why not just click past it which takes all of 5 seconds