The story of the Merlin V12 is really the story of E.J. Houdry, a Frenchman who came to the US in 1930 and, with plenty of help at Standard oil, perfected fluid catalytic cracking of hydrocarbons.
FCC gave the US AVgas with octane as high as 150 by the end of the war. This allowed much higher engine manifold pressures than the Germans before detonation, who had mostly 87 octane fuel throughout the war. Engine power is roughly proportional to manifold pressure.
Source: a long rabbit trail of trying to understand why the Daimler Benz DB 605, while seemingly far more advanced on paper, was never better than parity with the smaller Merlin during WW2. Houdry being in occupied France at the wars' start would make an interesting alternate history.
I've understood that a large reason why the Allied fuel had higher octane was use of TEL, and that for some reason(???) the Germans never figured it out (sounds unlikely?) or they couldn't produce it due to some other reason. Is this completely wrong, did the Germans also use TEL?
My knowledge about the role of tetraethyl lead in AVgas is limited to basically Wikipedia. But overall octane driver for both sides was feedstock quality (oil or paraffins).
The Wikipedia primary source that shows the Germans also had TEL production is given as this book:
Courtesy follow-up after some more digging. If you Google for "Technical Report 145-45" you'll find a PDF with the US report on German fuels that clearly indicates their use of TEL, and at what concentration.
The other major take away from that is the lean/rich Octane equivalents of the C-3 fuel were like 90/130 by wars end. So pretty good rich performance, but laggard lean, which would of course impact engine consumption rates in the larger DB 605.
The allies had widely available 100/130, and some 130/150 AVgas in the Pacific best as I have been able to find.
It comes back to the limited quality of hydroforming then mixed with synthetics for the Germans, vs FCC for allies. US crude wasn't of great starting quality, but they were better able to refine it at scale.
I believe the US late war high octane avgas was 115/145. 100/130 was indeed widely available more or less the entire war.
I think the British had something they called "150 octane", but I'm not sure that really was "better" or even different than the US 115/145, or was it different testing protocols etc.
Interesting, especially the 115/145. The octane equivalent #s from that era seem to be all over the map.
If actually 115/145, that's a big delta in performance for lean operation, and certainly helps the narrative. Do you have a primary source? I'd like to read further.
Regardless, what's certain is the Germans were in the high 40s mmHg for manifold pressure in late variant DB 605, vs the Allies were in the 60s mmHg for Merlins.
The US won WWII through superior logistics as much as anything else. The Japanese strike at Pearl Harbor was in recognition of the fact that they would lose any prolonged war with the US because of the manufacturing capacity that we possessed.
The German MW 50[1] used a mixture of methanol and water. It could be fitted to the BMW801 (Focke-Wulf Fw 190) and the DB 605 (Messerschmitt Bf109) engines.
There was also the GM-1[2] which was a nitrous oxide injector and mostly used for high altitude work.
Water methanol injection was invented by Sir Harry Ricardo, a British engineer.
It is my understanding that his book "The High Speed Internal Combustion Engine" was the definitive text on the topic of internal combustion engines in the 1930s and 40s.
"zeolite" materials as catalysts are something you are exposed if you study materials science (my formal education). Also W.K. Lewis is a name you'll be exposed to if you dip a toe into chemical engineering. Zeolites and Lewis are central in the FCC story.
Not specifically about this topic, but "Oil & War: How the Deadly Struggle for Fuel in WWII Meant Victory or Defeat" is the most definitive account of the overall fuel supply factors that I am aware of.
That book probably covers the operation to get fuel across the Channel for the D Day invasions. I'm fairly sure Brenzett Aeronautical Museum had a section about it along with some pipe and equipment when I went a few years ago.
There were so many astonishing developments in the background to support the front end fighting which are so easily overlooked.
Thanks for the book info, I've flagged that to get at some point.
The Boeing Museum of Flight once offered rides in a Merlin-powered P-51. I was first in line that day, and was smiling for a week afterwards.
From the book:
"One day I happened to be chatting near my home with an RAF Wing Commander (retired) now dressed in dark grey slacks and Norfolk jacket. Suddenly out of the blue and on its way to Coningsby was a fighter of the Battle of Britain Flight right over our heads.
We both stopped talking and looked up--the crisp steady
note of the old Merlin as joyous a sound as ever it was all those years ago. The ex-Wing Commander said absolutely nothing-- then he sighed. It was such a poignant sigh. I felt it must have invoked so many memories of the days when the Wing Commander was young, daring and vigorous and like a Knight of the Crusade had leapt onto the Spitfire and its Merlin to ride into the pages of history.
The silence was still uninterrupted. Thoughts and memories began to flicker through my mind. I remembered crashing badly and the terrifying sound of things being torn apart; closing my eyes as the ruptured earth flung pieces of metal over my crouching head; the peculiar smell of oil, petrol and glycol and damp earth hanging in my nostrils. Then the panic as I struggled out of parachute, harness and shattered cockpit--and then the silence. An almost deathly silence. As I prayed a word of thanks over the crumpled wreckage and the large black mass buried in the soft ground--once a powerful, gleaming engine--I heard this sigh. It may have been a pressure-relief valve, or glycol, or oil on hot metal, but in the emotion of the moment it became a sound I shall always remember. What better epitaph to a wonderful machine and a magnificent engine than to call my book Sigh for a Merlin?"
There's another passage in that book that this article might help explain: IIRC, there came a time when Henshaw and his fellow test pilots experienced some life-threatening engine failures of the Spitfires that they were testing, at one point forcing him to make a crash landing in an urban area (perhaps the Wednesfield crash of 7/18/1942 mentioned in his Wikipedia entry? And is that perhaps the incident mentioned in the last paragraph of your quote?) The cause was traced to something like a small change in the order in which the engines were assembled. That the British-built engines were hand-crafted seems to make this less surprising.
I would guess that, being hand-built, it would be trickier to keep them well-maintained, and require a particularly well-trained and skilled corps of artificers. The article does not get into it, but I wonder if there were differences in reliability between the Packard- and Rolls-Royce- built Merlins?
It was the skewgear (drive shafts) for the magnetos which were failing. They had a few go out before they traced down the problem. I love the sound of a Merlin.
I agree. Recordings not only don't do them justice, they don't have any similarity at all to how they sound. I recall standing in a field and a P-51 went by overhead, at minimum altitude and full throttle. If one hasn't heard that, one can never understand :-)
Agreed on the Vulcan - having watched XH558's final flight, a low-altitude slow climb opening the throttles to max, the way the Olympus engines split the atmosphere behind the aircraft isn't just something you hear, it's something you feel. Definitely can't capture it on a recording. The fact that it set off about 20 car alarms at once is testament to its power!
This is part of a long and interesting story I don't have time to find the right links for...
In the UK compared to the US, say 1850-1950, the premium commanded by skilled labour over unskilled was always much smaller. Or another way to say that is that they had a very large pool of skilled people. This was part of what allowed them to do many interesting things first (like railways), but also as time went on discouraged automation. For example lots of first world war UK munitions factories imported the latest American machines, suddenly needing to modernise once their skilled men were conscripted. This is, I believe, part of why Rolls-Royce were doing things described in the article -- call it a first-mover disadvantage relative to Detroit.
There is lots of interesting data about all these things. If you want to think about robots taking jobs and all that, then understanding (for example) the cotton industry circa 1900 is actually a great place to start. If some factories employ 1/4 the workers of others, that sounds a lot like having 3 robots... transistors are not involved, but certainly dollars (and unions, and taxes, and shipping) are.
This does sound like something that needs a book to expand on it.
Interestingly enough if you look at the modern UK car industry, there are two kinds of success: large factories with overseas management, and small boutique high-tech companies with local management doing similar things to the Rolls-Royce described here: supercars, F1 etc. All small hand-finished production runs.
My hypothesis is that something about the class system causes management-worker relations to break down at scale. Perhaps this can be avoided by having a business small enough for the boss to be regularly seen on the shop floor, and professional enough that the input of individual skilled workers is valued.
The last "British" large-run carmaker, MG Rover, collapsed in ignominy and the directors narrowly escaped prosecution for defrauding the investors in the previous round of rescue.
Robert Peston in his book WTF points out that the management performance of UK companies is bimodal - either truly world class or awful - I suspect those in the "awful" category are those where old fashioned class stereotypes still rule.
Many books! (Although sadly too many are just modern political battles dressed up in earlier period costumes.) For now let me recommend https://pseudoerasmus.com/ (and his book lists) as an honest guide to all this, for those with enough time!
Postwar UK is indeed a different story. My reading of the demise of Leyland - Rover etc. leans towards it being a parable about communism never working, rather than about market wages & skills & how much automation paid off where & when, as for the century before. But indeed small firms (and foreign firms) escaped this fate.
I have worked between US and UK companies for a long time now and I do find US companies (of the multinational sort) generally have the mindset, management and engineering culture that leans more towards automation. One of the reasons, I suspect, is that US companies have to think about scale sooner or more often, so standardisation, automation and coordination needs to be adequate to allow it to succeed at scale.
One of the revelations of the 1851 Great Exhibition was the difference between US exhibits and those of Britain, France and Germany. In some ways embarrassing because the US was the only nation (and somewhat ridiculed as a result) not to sponsor their nation's attendance it showed a simplicity and practicality that was often absent in the European equivalents.
Notably the reaper and other agricultural machinery and Colt firearms that were clearly ahead in both means of production and practicality.
There's been quite a bit written that it was the first indication that the world's centre would be changing. The US had none of the baggage and history that went with having hand made, high skill crafts and could go straight to production in large numbers. Because they were starting from scratch across much of the nation they had to. Which turned out to be a huge advantage. Much as we've seen more recently with developing nations going straight to mobile phones without landlines first, or China short-cutting much of the industrial development the West had to go through.
There's been a couple of credible books making the case that most of the changes of world centre through the ages have been for similar reasons.
If I can bring any titles to mind I'll edit. Offhand I can't remember.
Thanks that is extremely interesting info. I have noticed when talking to Americans and reading about American manufacturing, I get the sense that workers are not expected to be particularly skilled and that production is designed with that in mind.
I am from a Nordic country and we tend to follow the German style system of vocational training where you go in an apprenticeship and get a certificate. I have tried to understand the American model but it seems less formalized to me. It seems to be more company specific. You get trained to do a particular job at a particular company.
The American system is to have no overarching system. Our empire is too large - we have to accept people from numerous systems and varying levels of ability. Alaskans and Alabamans have to work alongside Germans and (both kinds of) Georgians. So the company trains you to do what they need.
Not an expert but it does sound like American car-making for instance is lower-skill than German, today.
But I'm not sure about manufacturing as a whole. The things America is competitive in exporting tend to be pretty high-tech. I found an article I remember about a jet engine factory (to keep this on topic!) which sounds very far from hiring the bottom of the barrel:
"Machine that Changed the World"by Womack discussed this, in both the PBS series and the book.
The comparison they used was the Toyota line at Tahara for the Lexus LS, and the Mercedes S-class line at Sindelfingen. (American car-making, nowadays, would hew closer to the Japanese example...)
The gist was that while the Lexus workers were expected to be hugely attentive and detail-oriented, they were nowhere near as mechanically skilled/trained as the Germans. But, they didn't have to be; the car they were making, and the process by which it was made was designed around workers of that skill level.
The Mercedes, OTOH-(if you have ever taken apart a W140 S-class, this ain't gonna surprise you...) clearly needed a team of people to carry out the same assembly tasks due to ease & simplicity of manufacture not being a design consideration.
Womack goes on to talk about a special "hand-assembly" line at Volvo, supposedly to ensure that certain custom-ordered cars get almost individual attention from a small team of experienced techs, so as to improve quality. It doesn't end up working out that way; throwing more, better-trained, workers at the problem increases costs far faster than refining the design & feeding that back into the manufacturing process.
It's a fascinating book, and I look at it every time I hear how Tesla is running their factory....
Incidentally, I think this is why so many people think American manufacturing is dead. Our stores are filled with cheap imported crap and it’s easy to think that’s all there is. But you don’t find a new 787 in the local shops, so it’s easy to forget about.
Depends on your definition of full employment. By some accepted definition, the US is at full employment. But other definitions are possible and in use. (Even Wikipedia mentions a few. https://en.wikipedia.org/wiki/Full_employment)
For what Americans consider trade schools, like welding, plumbing and a whole bunch of others, there are apprenticeship style training. It can even depend on the state.
Line workers in a car manufacturing plant are very low skilled and are jobs that anyone in theory could do. Most manufacturers in the US around the South (where I live) are in very rural areas. It would be hard to find a huge population of skilled workers to fill a plant.
BMW, Mercedes, Hyundai, and Kia have plants near me. The BMW plant is the largest in the world. I believe Toyota and Mazda are opening up new sites as well.
If you like this then I can recommend "The Ministry of Ungentlemanly Warfare: Churchill's Mavericks" by Giles Milton - it starts with British inventors creating an important new weapon (the limpet mine) from sweets, condoms and bowls from Woolworths in a shed (of course)...
The boffin/craftsman side of things seemed particularly important to the UK effort in WW2.
In this vein, R V Jones "Most Secret War" is great if you haven't read it -- about the cat & mouse game of radar development, from a guy deeply involved:
Here's some info about the guy that played an important role in figuring out the fuel mixture that made these power outputs possible. It's an equally interesting read.
Wonderful piece for those interested in early WWII aviation. There are lessons for software development in there. Brad Cox's classic Planning the Software Industrial Revolution [1] highlights the importance of gauges to Eli Whitney's project to built firearms with interchangeable parts, and asserts we need a similar technology in software to enable construction from reusable components. In Most Dangerous Enemy [2], Stephen Bungay points out that it took 2.5 times more man hours to build a Spitfire than an Me109. German production engineering was far better than British. This piece illustrates that perfectly. Rolls Merlin engine was a great piece of design engineering, but it was inefficient in terms of production engineering. What is intriguing about this article is the detail on the effort needed for Packard to port the Merlin design to their production engineering standards, and then for Rolls and Merlin to share design changes. Effectively sending each other pull requests!
> need a similar technology in software to enable construction from reusable components
People have been attempting this for a long time with only moderate success. It's where object orientation came from: objects were supposed to be reusable. Similarly with UNIX pipelines. The new enthusiasm for package managers produces some absurd results (left-pad) but is generally heading in the right direction, as is the trend that everything that's popular enough becomes a language feature or in the standard library.
Yeah, object orientation never really worked for making reusable lego-bricks.
The functional programming people have been at this game for far longer (and are building on top of mathematics started around the 1940s). There's some encouraging developments, including some that are making it into mainstream languages.
Yes, libraries (including standard libraries) do tend to work really well, too.
Interesting, given that I've read that Americans were far better at mass production than the Germans. My impression is that Germans engineered their hardware better than Americans but they were not as good at mass producing it fast.
So if I understand correctly, the British was exceptionally slow at manufacturing compared to the Americans then.
I read years ago that the Spitfire required twice as many labor hours to produce than the Me-109. The Germans were pretty good at simplifying the design so it could be mass-produced.
It depends upon your definition of "slow". At mass production, maybe. But maybe faster at changing and iterating on designs due to being more flexible and adaptable.
Tangentially related to this article is Simon Winchester's latest book "The perfectionists: How Precision Engineers Created the Modern World".
One of the chapters in this book is about the differences between the hand-built cars of Rolls Royce (and their origin story which I never knew) and Henry Ford's production line that required interchangeable precision parts.
During a childhood visit to a car factory I noticed how the panels for the small, mass-market, fairly horrid hatchback went together perfectly whilst the panels for the luxury low-volume saloon needed lots of men with actual hammers to bash into shape.
The tooling used to make the hatchback had cost a fortune and was the finest German stuff. The tooling used for the luxury saloon was a lot older and therefore worn. There were no backup dies in the worn tooling so over time the panel fit only got worse with once fine details no longer sharp.
The executives driving their luxury saloons would probably have been horrified if they had known that it was the cheap cars that went together properly in an exact manner with their cars being the ones needing to be bashed to 'look right'. They would also have been horrified to see the same facility used for making panels with everything being 'just being a bit of tin' to the staff rather than their pride and joy.
Having had the reality of luxury exposed as it being hand made, bashed into shape at such a formative age I have always wanted the robot built products, e.g. the mass market car rather than the bashed into shape expensive version.
The deluxe cars of today are still very much 'bashed into shape' in ways that they always have been. The BMW car brand 'Rolls Royce' very much hand-craft cars as they always have, they are not doing it wrong by not re-designing their products to make it so a rival can churn out millions of identical clones.
The original aerospace 'Rolls Royce' was in the same position, making a modest amount of engines and not in 'total war' mode. Their less than precise drawings were fine for what they were doing, they had people to bash stuff into shape, 'luxury auto style', with that making economic sense. The war changed everything though.
> That the Merlin outperformed the Allison at high altitude is hardly a condemnation of the American-designed engine. In its element (up to about 15,000 feet), the V-1710 was robust and reliable – utilizing fewer than half the number of parts found in a Merlin. It was also extremely adaptable to different configurations of gearing, rotation direction, accessories, etc. The Allison engine is a showpiece of modular design.
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Engineering is finding the best compromise for a particular set of requirements.
As a kid I remember reading an article in a hot rod magazine about a drag racer powered by a Merlin engine. It was quick, as you'd imagine, but easily overpowered the tires of the time so not as quick as it could have been. I wonder what happened to it.
An interesting fact is that former Packard engineers were fathers of archetypal "American V8s." Some solutions they saw on Merlins were replicated 1-to-1 in their own works like cylinder head designs.
And yet apparently, some actually do have to regurgitate 1980's-era copy from a German automobile makers' successful advertising campaign in (at least) the British market. As though doing so were some kind of victory. Leaves me so sad.
FCC gave the US AVgas with octane as high as 150 by the end of the war. This allowed much higher engine manifold pressures than the Germans before detonation, who had mostly 87 octane fuel throughout the war. Engine power is roughly proportional to manifold pressure.
Source: a long rabbit trail of trying to understand why the Daimler Benz DB 605, while seemingly far more advanced on paper, was never better than parity with the smaller Merlin during WW2. Houdry being in occupied France at the wars' start would make an interesting alternate history.