Calum I have been a WWII aviation buff for my whole life and I am in my 50's. You have improved my knowledge vastly and contributed to the understanding of the WWII aviation history! The book is too cheap for its impact.
I just finished the book last night, fantastic! I laughed every time the Germans complained about the Mosquito again. And I finally learned why DB wasted so much effort to install a DB605 onto a Spitfire Mk 5. Thank you so much for this amazing book. *****
Focke Wulf actually built over 100 of a fast twin engined wooden fighter named Moskito, but the Germans happened to get their Tego Film factory, which made their wood glue, bombed, and the replacement glue wasn't as strong. After some crashes caused by delamination, they cancelled the program.
The reason they failed with wood had to do with the fact that Germany had no comparable replacement to the Aerolite 300 adhesives from Norman DeBruyne's Aero Research Limited. I have the book "Bonded Aircraft Structures" written by him.
@@oceanhome2023 It pretty much was the reason De Havilland could succeed. I think to myself, if the Horten bros. got the glue, the 229 aerostructure would be cutting edge.
Very interesting video. To the first question: the Germans did actually build their 'version' of the Mosquito: the Focke-Wulf Ta-154 Moskito (a Kurt Tank design). Production numbers were quite low and from what I've read they encountered delamination problems because of the resin/glue used.
Bit surprised that at 14:30 you said ignoring Ricardo and fuel injection was the biggest British mistake. I thought it was ignoring Frank Whittle and his turbojet work of the 1920’s to early 1940’s.
That is not true, Whittle got blown out in 1930 due to three reasons, One he cocked up his maths, two, there is no threat requiring an aircraft that can do 500 knots at 60,000 feet to deal with (The RAF are still flying fabric covered biplanes from grass airfields at this point) and thirdly thanks to the Depression, no money. It was the RAE who said no, not the government. Whittle's work was however monitored by the RAE and as early as 1936 they were starting to take some interest. However, the engine that Whittle had proposed burnt 4 times the amount of fuel at 300 MPH at Sea level that a piston engine fighter would have and it would have had issues getting off the ground in the first place. They did however note that at 400 MPH, the engine was very impressive. The Fuel efficiency for fighters up to 1936 was important. Radar did not exist and thus fighters needed endurance to fly standing patrols. Of course, when radar did become a practical early warning device, the endurance and fuel efficiency could be dropped for speed and rate of climb as the fighters could be kept on the ground. At this point, the RAE seriously started looking at jets, in both the form of A A Griffith's axial flow Turboprop (Griffith being the individual at RAE who shot down Whittle's maths in 1930) and Whittle's Centrifugal jet and both stated to get government funding in 1938, with full scale development of Whittle's W.1 engine and an aircraft to put it in being signed off by the Air Ministry in 1939, before the war even started. In reality, the British were the first to put government money into development of Jet Engines. Giving the development contract to Rover however was a big mistake. Like a lot of things about the British war effort, the reasons for decisions being made ended up being locked up for 30 years because of the official secrets act, and what was published in between tended to be a load of horseshite.
Sounds like it is a great companion to to the other books covering piston engines in the period. Not only those that made it into service but also those that didn't.
It concentrates on engines used in service, but it does cover some key reasons why a few experimental engines failed - but it just doesnt devote huge space to them.
Very interesting book. I bought it. Too bad it doesn’t elaborate on the DB605A-1 issue about the possibility to use 1.42ata and 2.800rpm settings, even for a short time. Could the 109G-6 use such max power settings? Since when? I’m very interested becouse italian Series 5 fighters mounted that engine and did some climb test probably using those settings. The difference in performance using the max ata/rpm was HUGE.
Congratulations for the book, some of the things I already knew but a lot of the stuff was unknown and surprising. I'm particularly interested in all the detailed drawings of the various engines components you show, is there a digital archive similar to what the germans have done with the V2 blueprints? Thanks and congratulations again.
Yes also interested. I am trying to collect original drawing images of old aircraft, & engines and use them as a screen saver. Just because the images are so cool and to appreciate the amount of work done.
Very interesting information. Thanks for share your knowledge and investigation. I'll buy RU-vid book as soon as possible. Best Regards From Spain. Really seems Hispano Suiza isnt design with performance in mind.
Just read the book. Was looking forward to reading abut the ups and downs of engine developments and some technical insights of engines such as the peregrine, centaurus,sabre, griffin, hercules, allison, r2800 british & us merlins plus the german kit but somewhat disappointed. Great for german info and if you like superchargers and fuel composition. Fascinating stuff as to why the germans hampered themselves and the technical advances from the jumo 213. Still very informative and definitely worth reading.
Callum, Thanks very much for that. Got your book from Mortons (excellent) and you have here given some inkling of your thoughts about the SV motors which perhaps are only given light attention compared to the Merlin, DB and BMW motors. I appreciate it is a lot of work because the sheer comprehensive scope you have given to these crucial aeroengines has to leave out something. But I would like to see an account of the hard long development (followed in my view to ultimately successful sleevevalvers, both Bristol and Napier Sabre. I am thinking of the Hercules in particular produced in huge numbers, which did literally a lot of heavy lifting (transforming the Halifax for example)
Yes the Hercules could sort-of have been sneaked into the book because it was used in the Beufighter, but, I had to take the view that as the slightly inferior speed of the Beaufighter relative to the Mosquito, relegated the Hercules powered aircraft to an anti-material role, generally not involving actual air-air combat, that I had to exclude it or risk the book being too diluted (as it was already at the limit of practical size). Therefore, I chose to "tell the story" of the sleeve as a technology with the Sabre for the most part for practical reasons. I dont think adding in the Hercules would bring in any profound technical lessons which didnt also emerge in the Sabre`s development. Slightly ironically, in the Bristol archives, there exists about 5x the material on the Hercules than remains for the Centaurus. But I thought that to go through that, would have been simply impractical for this book, so I had to chose another engine to use as a "vehicle" to discuss sleeves. The Hercules is a very interesting engine, and probably deserves its own book really.
Callum, Thanks so much for taking the time out to reply. I kind of suspected that an already fulsome read might make the plot a bit Unwieldy with details of the Bristols and other redials. If in the fulness of time we might persuade you to do such study of the Bristols, Fedden and his sudden resignation etc I promise to buy !! You deserve every success best wishes J
There appears to be a lot of data regarding the Allison V-1710 indicating that it had design flaws that prevented it from ever being a high altitude performer. As I recall, the intake manifold was a major issue that caused uneven fuel distribution and detonation. Can you elaborate on other issues?
Please note error in my narration at 13:44 I accidentally read out the company heading date not the report date, so the correct date with respect to injection is 20th June 1932.
Messerschmitt didnt want to build a wooden plane, but the Russians had no problem building mainly wooden constructed planes. The Napier saber engine had the advantage of engine timining once set at the factory never changed during the engines lifetime but the engines constuction tolerences were more exacting than the Rolls Royce engines. The maintance crews also didnt help, doing things to the sabre that shocked the Napier engineers. The sleeve valve design was inherntly superior than the overhead valve design as it wasnt suseptible to engine nock and didnt require water injection unlike the R2800 in the thunderbolts which needed it aswell as turbo supercharging to get the same hoursepower output as the Napier Saber and the Bristol Centaurus engine which also had sleeve valve setup.
@@johnburns4017 Well, there's a difference between whether or not we like him and whether or not he's right. Setright was "quite a character". I'm sure a lot of people liked him. He dressed like a 19th century tailor and smoked Black Sobranies. He looked a lot like a Jewish Rasputin. He was also known for his bombastic writing style which could be simultaneously funny and infuriating. I think of him as more of an entertainer than a serious writer, almost in the Clive James style when it came to motorsports but with more ego. But Setright, to give him credit, knew his audience and he knew what that audience liked. He was a "car guy's writer". Probably the most obvious one. He gave his readers what they wanted to hear. I'm sure there are those who genuinely believe that his book, _"The Power to Fly"_ is really worth US $500. Confirmation bias - the desire to believe that authenticity is directly linked to price - suggests that it wouldn't matter whether he was right of wrong, his audience would take him at his word. So when Setright claimed the Sabre engine was capable of 5,500 hp, a lot of people took him seriously. But most of those people were "car guys", who he had ported over to the aviation sphere. They were probably used to some pretty astronomical power claims, even in 1970, when the book came out. But there is no reliable evidence that it ever produced more than 3,200 at WEP - not even from Napier - and even then it was consuming prohibitive amounts of oil. The E.122, designed for 3,500 hp, never ran. Calum explains why this was not possible. The stress on the sleeve would have caused the engine to seize because, due to the expansion of the sleeve at detonation, there would be insufficient room between the sleeve and the bore for proper lubrication. Heat would cause further expansion and the engine would blow up.
The Germans could not build a wooden plane for one simple reason: they did not have the glue technology. They used simple hide and fish glue, casein glue, and mucilage. They wouldn't hold up in an aircraft especially when wet. The Allies had PVA, resorcinol phenolic, and aliphatic epoxy. PVA was actually invented in Germany but never became succesful commercially. The Mosquito was built with resorcinol adhesive on the major joints. It worked well until planes were shipped to India where moisture and heat could degrade the glue. Aliphatic resin glues used for woodworking in the US are actually stronger than the wood itself.
I have read that RR were working on a sleeve valve design called the "Crecy" and would be a step up from the Merlin and Griffin line I am curious why there are no examples of pure 2 stroke aero engines as they offered excellent power to weight qualities and would have been cheaper to mass produce.
@@CalumDouglas Makes sense although sleeve valves appeared to have overcome this drawback somehow, incidentally I have bought your book I just need to make some time to start reading it, it is a good looking tome I just wish I could have it in PDF to save my arms lol.
Its very simple, the british had access to the almost endless or massively greater, resources from America. Once FDR and the pro entry to war political elements defeated both by open means and less visible means, the groups opposed to entry to the war, britian, and less directly the soviet union had a tidal wave of access to critical strategic materials. Think what access to even simple resources like nickel, chromium, copper, silicates etc to the construction and maintence of combat aircraft. Once America entered the conflict, that was it, game basically over the Axis was finished.
Could the German Jumo 222 have been the much-desired powerplant for the Bomber B programme had iit not been cancelled, was it anywhere near series production at some time?
It does not appear to have ever reached mass production readiness. I have a "projected plan" from Jumo dated 11/10/1941 in which the 222 was projected to start mass production in May 1943, reaching a peak of 1000 a month by July 1944. Actual data for engines produced do not list the 222 at all, other than of course a lot of prototypes and test engines. Without the difficulties in bearings and oil due to shortages, I have no doubt it would have been a viable engine eventually.
Hi Callum, I have a burning question that has arisen after watching some of your stuff. It is , Do you think that the Germans suffered badly by not being involved in the Schneider Trophy ??
Yes, but remember it went further than that, in the Versailles treaty they were also prohibited from developing supercharging and also engine above a certain power output, so it is more than just the prohibition from the races. If you are interested to that extent, you really do have to buy the book, the first 127 of the 480 pages are on the 1930`s - and almost all of it is from archival documents. You`ll find a lot of new details
I never quite got the point of the added complication of a sleeve-valve design in a water-cooled engine? In an air-cooled radial supposably it reduces cylinder head temperatures, but if the Merlin 130/131 could crank out basically the same power as a Napier Sabre, why do it with sleeve valves?
I wonder just how many engines (Merlin or Griffon) RR could build versus the Sabre. The Sabre in my opinion wastes a resource that at any has. Skilled man hours.
Interesting. The RAE at Farnborough tested the Mustang saying that the laminar flow wing made little to no difference to performance. One web site gave photos of a letter that Mustangs must not be laminar flow as it would be giving away secrets to the a foreign power (Britain), even though the Mustang was basically a British plane. I can't find the website now. :( Makes me think the version RAE tested was not a laminar flow Mustang. Making me think they made two versions, one for the US and one for the Brits.
I dont know, but the Germans tested the Mustang wing and found it to be excellent, with considerably lower drag than the non-laminar equivalent. The only reason the 109 didnt get one was because they used leading edge slats, which would ruin the laminar flow, deleting them meant increasing the wing area by 15% to compensate for the loss in lift in take off and landing, the wing was designed but considered too big a change in production to impliment, and they also considered their manufacturing to be unable to reliably get good enough panel fits to make it work. So it was never employed (I have all these reports and the drawings of the 109 laminar wings).
@@CalumDouglas The RAE tested a P-63 not a Mustang on laminar flow wings. Wiki mentions it but does give a source for repeating (not that I believe Wiki most of the time): _British engineers, like the Americans, had a growing interest during World War II in the application of laminar flow airfoils. In an effort to learn more about the practical application of laminar flow airfoils, in 1945 the Royal Aircraft Establishment (RAE) undertook a flight test program with one of the two P-63As that the United Kingdom had received. The aircraft was equipped with a wake rake array mounted outboard, behind the wing, to allow the momentum deficit, and thus section drag, to be measured._ _The RAE first tested it in an "as delivered" configuration. The wing airfoil was designed to support laminar flow to 60% of chord. In the "as delivered" configuration, a profile drag was measured which was representative of the wing section with boundary layer transition at the leading edge (0% laminar flow). Reducing the surface roughness reduced the drag at low lift coefficients to a level representative of laminar flow to 35% of chord._ _Measurements were made of the surface waviness. This showed peak wave amplitudes, above the mean, of approximately 0.011 inches over a two-inch span. The standard waviness criteria shows the critical wave height to be 0.0053 inches for this application. To reduce the waviness, RAE personnel stripped the wing to bare metal. The wing was then sprayed with two coats of primer paint and a coat of paint type filler. After the paint was dry, it was sanded in a chordwise direction, using sanding blocks, whose curvature matched the local surface curvature. This was repeated several times._ _Surface waviness was then measured and found to be no more than 0.005 inches. In flight, this configuration was found to have a profile drag representative of boundary layer transition at 60% of chord. This gave researchers an idea of what level of wing surface quality was required to actually get the benefits of laminar flow airfoils._ The ref is: Smith and Higton 1945.
The issue of laminar flow on the Mustang wing I thought was proven that it isn’t so. The accuracy and surface of the wing must be a perfectly polished finish to achieve a near laminar flow. In reality due to manufacturing tolerances, paint finish, normal surface wear and tear in the field it did not maintain a laminar flow over the whole surface of the wing. The wing though was optimised for the least drag at economical cruising, but had poor low speed handling and not great handling at high mach numbers (as the Spitfire for example). I believe Gregs Airplanes on RU-vid has done an episode on this issue.
@@briancavanagh7048 Correct, matching what I have read. The highly polished wing surface was essential. It needed polishing after every flight, as a small glitch could upset the air flow.
@@briancavanagh7048 Gregs videos are frequently wrong on many key technical aspects. He has decided that since the Mustang wing wasnt wholly-laminar, that it didnt work and wasnt the real reason it had low drag. This is utter nonsense, the truth is that the P51 wing was merely lowER drag than conventional profiles, Greg has put out a very misleading video stating the opposite. I offered him German wind-tunnel reports on the Mustang wing as well as Supermarine estimates saying the opposite - he wasnt even interested in looking at them (go and read the comments, you`ll find the conversation). One of many huge howlers he makes, as it happens, like when he makes the ridiculous claim no German engines used the Mikulin style swirl throttle - when it was on every Jumo213 ever made - or that the P-38 took 90% of all PR photographs over Germany in WW2.
Hi Callum, interesting video but your opening question/answer was highly truncated and left the viewer under-informed because Focke-Wulf DID develop their version, the TA-154. A bombing raid on the factory producing some of the moulded wood componentry was the only thing that scuppered it proceeding toward mass-production.
We are not discussing the same thing, the 154 is not a "copy" of the Mosquito, which is what what Göring was discussing. He was actually making an order to make a DIRECT duplicate, i.e actually measuring a captured Mosquito and producing an identical copy. The 154 has no similarity with the Mosquito in any way other than that it is wooden and has 2 engines. It is a totally new aircraft, and was designed before the Germans ever captured an intact De Havilland.
It is true that the Germans had internal administration problems. First of all, there was significant resistance in the regular military and industrialists, who were from old line upper class circles, to National Socialism. The back and forth about the mosquito is a perfect example. This is why the SS created many avenues of weapons and general scientific development. To get around the foot dragging and profit seeking of the old guard.
By 1942 the Germans had already halved the content of things like chromium or vanadium in many of their alloys. That was while Germany was still seen to be on top.
A few corrections. Ricardo wrote in detail about the sleeve valve design. He was saying the exact opposite: the sleeve valve is ideal for high boost BMEP. The wear on the outside of the sleeve in all sleeve valves was negligible. The ports on the sleeve hide above the junk head at TDC compression, so during the high pressure events, the ports do not weaken the sleeve. No issue there. The advantage the sleeve valve have over the poppet valve engines at high BMEP was the elimination of piston ring wear due to sleeve rotation. That is a huge advantage. As for the piston side loads, the sleeve rotation again helps, allows the load to be taken hydrodynamically. This is why all the sleeve valve engines (Bristol and Napier) had very small piston skirts, they did not need long skirts. In the labs, sleeve valves could handle crazy boost pressures. Ricardo recorded 500 psi BMEP in the late twenties. One reason why the Napier Sabre did not go very far is it lacked a good airframe. The Typhoon and Tempest were overweight and fat, much like an American F4U. Empty weight of 4 tons is not the prescription for a high performance air superiority fighter. It maybe OK for a fighter bomber, but not an air superiority fighter. Also, the Sabre could not fit well in a Spitfire, so there was no way for it to surpass the Griffon. Other problems was that the extreme complexity brought in problems under mass production that took time to figure out. Additional issue was that Rolls Royce had more money to lobby the air ministry (remember, the fundamental reason behind wars is money). But the indisputable genius of the Sabre design is proven by the fact that Rolls Royce got the contract to build a bigger version, the Eagle. If you want to see how we can now exploit the friction advantages of the old sleeve valve engine, look here (read comments and follow links): ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-rFHq1bzuOQo.html The Mustang was a very poor design due to its excessive weight. In anything other than level flight, the P-51 was mediocre at best. The Mosquito was not particularly light. Wood construction and all, it was not that light. A similar aircraft, for example, the Mitsubishi Ki-46, was a lot lighter.
Mustang and spitfire were very alike in weight and dimensions. The difference was in the wings. The mustang was optimized for low drag. This gave more speed and less fuel consumption. The spitfire was more optimized for lift which meant better climb and manouverability but more drag. Spitfire was intended as an interceptor. The mustang prooved to be best a long range escort. Each excelled in its specific niche. Treating them as equals for comparison is not a valid assessment. RR produced about 100,000 merlin's. Packard produced 60,000.
@@francoistombe Yes, you are to some extend correct. However, the empty weight difference between similarly powered Spits and Musts is very substantial. About 900 kgs. That is huge, and the reasons is the poor design of the Mustang airframe, compared to the exemplary design of the Spit. Of course, the P-51 was far cheaper to produce than the Spit, especially given the very low labor quality available in the USA. Second is that the laminar flow wing performance was substantially over-rated. It killed too much lift, for too little benefit. The Spiteful experience proves that. Second important point is that there were solutions to give the Spit more range to do the same task as the P-51. But wars are about money, and nothing else. Not that it would have made that much difference, the Luftwaffe was so weak by that time, the outcome would have been the same, other than some aircrew lives saved and some of the German super aces having 50 or 100 fewer kills. One important factor. The P-51 great speed on level flight for the modest 1500 hp of the Merlin 61 was mostly due to very good job on the radiator cowling and exit nozzle. The laminar wing had little to do with the speed advantage of the P-51. Of course, the larger wing of the Spitfire was the other reason. But the larger wing more than paid off for most fighter operations, including climb, high altitude work, and dog fighting. The story of the Spitfire XI outrunning a bunch of trigger-happy P-51's by climbing away is very well known. Aerial combat is not a one dimensional affair. Cheers.
@@demetridar506 I checked back on this. The mustang was heavier than it's spitfire equivalent. It had to be. The difference in weight between dry and loaded weight on a spitfire was around 1600 lbs. The mustang took on 2000 lbs of fuel alone plus ammunition, external tanks etc. Heavier loading requires stronger (heavier) wings and the heavier wings and fuel require heavier landing gear. The mustang could never match the spitfire as an interceptor and the spitfire could never match the mustang in long range escort and ground attack.
@@francoistombe Not quite right ... As I told you, Spitfires IX were modified to carry very large amounts of fuel. The Spitfire XI carried huge amounts of fuel too, and had range similar to the P-51 The extra fuel that the P-51 carried (or some versions of the Spitfire) did not require extra wing strength. It would have been silly to set the specifications for 10 G's with a full load of fuel. The landing gear weight difference is in the noise level. The real issue is poor design standards, and overall design approach of the P-51 for cost reduction. In fact, recognizing the overweight standard of the P-51, North American studied the Spitfire load factors and attempted to redesign the Mustang in the form of the "Lightweight Mustang", I think it was the P-51H. It was still too heavy, but better. No question that the P-51 could not match the Spit in rate of climb, dog fighting abilities, low speed flying qualities, take off and landing performance, maximum diving speed, etc (anything that deviates from straight and level flying). But the Spitfire proved extremely versatile and ended up doing a lot of jobs that it was not designed for, i.e., long distance recce, aircraft carrier fighter etc and it excelled in all of them. Supermarine solved the problems that prevented fuel overloading AND retaining armament (related to lateral stability when adding fuel tanks behind the CG and nothing else) and showed that it can get huge range with internal fuel only. However, the RAF never pursued the project (probably out of short slightness) and the USAF by default would not replace the P-51 with the superior Spitfire due to prestige and loss of contracts from North American (to the delight of German super aces who got to raise their score). Another example of politics interfering with aircraft development is the project of generating a Merlin powered P-38. GM (who owned Alison at the time) bribed Congress to end the project and scrap the prototypes. Had this not happened, the USA would have had its own Mosquito. But as I said, wars are fought for money, and money only. And, by the way, the P-51 was not the only US fighter that suffered from excess weight. Pretty much ALL WWII fighters suffered from that. Perhaps the Tempest and Typhoon suffered too, but at least these planes had the over performing Napier Sabre. But the Hawker fighters, despite the large power availability, could also not match the Spitfire in dynamic non-straight line performance either. Cheers.
Perhaps I could add a small point. The spitfire came at the end of a long design evolution at Supermarine. The mustang was designed, built and flown in 3 months.
