Calum E. Douglas @CalumDouglas1 Twitter profile

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Calum E. Douglas

4 years

My WW2 Fighter Engines book is now available from the publisher. "I challenge anyone to read this book without cheering the triumphs or feeling compassion for those struggling against impossible odds." - James Allison, Technical Director Mercedes F1.

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Calum E. Douglas

@CalumDouglas1

11 months

A young German aviation fan, (Willi Maier, 15years old) wrote to Professor Messerschmitt in the middle of WW2, this is my photograph of his original drawing. He suggests several improvements to the Bf109, making the radio antenna internal, removing the tail wheel fairing, more…

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Calum E. Douglas

@CalumDouglas1

9 months

Then and now. I get a bit of flak occasionally from people saying I`m romanticizing the past when I laud the skills of WW2 engineers. I`m really not, as a professional engineer, who has spent years researching my own field, I actually have wartime reports which do all the…

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Calum E. Douglas

@CalumDouglas1

7 months

Later in WW2 the Germans (after a year of disaster) improved their aero engines by Chrome plating their valves. This used very little Chrome, but was a very intensive process for an application like a valve with about 27 operations per valve. The Allies meanwhile coated their…

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Calum E. Douglas

@CalumDouglas1

10 months

If you think WW2 was bad for the Allies in terms of losses in 1944, consider the following sobering facts and breathe a sigh of relief. 1) Due to the attacks on the German synthetic oil plants (totally unbeknownst to us) German production of Nitrogen and Ammonia was almost…

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Calum E. Douglas

@CalumDouglas1

1 year

PRO-TIP: If you want to be a mechanical engineer, read old stuff. Its usually far better for learning because 50 years ago people actually wrote things with a view that the content be useful, and clear to others. Its VERY hard to find such writing now, principally because…

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Calum E. Douglas

@CalumDouglas1

7 months

The RAF Bomber Command lost 55,000 airmen in WW2, although the USAAF also had losses which amount to not THAT dissimilar levels of horror, they did so in daylight and without really effective escort until quite late in the war. But arguably daylight without top class escort…

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Calum E. Douglas

@CalumDouglas1

10 months

Nobody ever writes about such dull things as "bearings" and "spark plugs" in military aviation history. After all, such things are unremarkable service items, which everyone had. This is very much what you`d think until you talk to engine people, who will tell you that in its…

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Calum E. Douglas

@CalumDouglas1

8 months

No, pioneering genius who was ignored during the late 1930`s, leading to a situation where she was forced to develop a carburettor fix to a problem which would never have even existed in the first place if her work at the Royal Aircraft Establishment on the RAE pressure injection…

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Calum E. Douglas

@CalumDouglas1

7 months

A fair question, the answer is because I was the first person to totally digitize the entire surviving German Air Ministry stenographic meeting records from Microfilm. So I could scan through about 15 million words digitally and so find all the important meetings regarding these…

Cole B.

@qizler

7 months

@CalumDouglas1 This is fascinating. How did you learn this?

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Calum E. Douglas

@CalumDouglas1

2 months

The internet is full of "nearly" good welds. This is very neat, and certainly fit for purpose (looks like it could be some generic framework), but the fact that its all lovely shiny colours means its oxidised. This is not to be celebrated, and means the shielding gas employed…

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Calum E. Douglas

@CalumDouglas1

6 months

A few WW2 aviation facts that remain not universally known. 1) The Hawker Typhoon was never envisaged as a ground attack aircraft, in fact it was supposed to completely replace both the Hurricane and Spitfire, both of which were expected by the Air Ministry to be technically…

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Calum E. Douglas

@CalumDouglas1

1 year

Having convinced themselves in the late 1930`s, courtesy of Dr Morley of the Royal Aircraft Establishment that Direct Fuel Injection was of no use whatsoever for military aircraft engines like the Merlin, there was a rather high degree of embarrassment when the complete high…

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Calum E. Douglas

@CalumDouglas1

1 year

Neville Chamberlain, British Prime Minister from 1937 to 1940, is possibly best known today for his ill-fated speech after his meeting with Hitler in 1938 where he declared that war with Germany had been averted. Generally he is regarded as a weak and militarily inept appeaser…

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Calum E. Douglas

@CalumDouglas1

10 months

Ten surprising (but true) facts about WW2 in the air in Europe. 1) Reading their highest level meetings about the Air War, the Germans were a lot more worried by the B-17 than they were about Spitfires from 1943 onwards > 2) The Mosquito was THE most discussed Allied aircraft…

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Calum E. Douglas

@CalumDouglas1

9 months

For those wondering what on earth all that maths is for, its because a valve might be accelerated at a thousand earth gravities multiple times a second in an engine, and the slightest error in the dynamic calculations makes the valve very sad and jam itself into the top of the…

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Calum E. Douglas

@CalumDouglas1

6 months

Its probably not true, but I was told a story once that when the Air Ministry people were looking at the lightning, they had it flown on one engine only on purpose so that it didnt raise questions as to why it had performance so far above the specifications. Just seeing one…

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Calum E. Douglas

@CalumDouglas1

8 months

Why didnt the British have a their own version of the Fw190 aircraft like the Hawker Sea Fury (first flight 1944) and play a serious role in WW2? The performance characteristics of the Fury are nearly all stunning, very heavy armament (4 x 20mm cannon), very high speed (460mph).…

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Calum E. Douglas

@CalumDouglas1

10 months

German WW2 technical intelligence report on the P-38 lightning. Visible here is the pilots left hand engine top nacelle, showing the General Electric turbocharger. Its exposed to the outside air to help cool the turbine blades. Its armoured, not to stop bullets hitting it, but to…

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Calum E. Douglas

@CalumDouglas1

7 months

The cockpit of the Focke-Wulf Fw190 fighter. Luckily for us it had an engine with a pretty mediocre supercharger for most of the war, which severely limited its performance at high altitudes - because it was in almost every respect a far better aircraft than the Spitfire (as it…

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Calum E. Douglas

@CalumDouglas1

11 months

The Professor wrote back on 28th August 1943, thanking him for his interest, and (his letter says) he enclosed a book about the manufacturing of the Bf109. The brief relief from wartime horrors in this otherwise touching exchange with a young German boy, broken somewhat…

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Calum E. Douglas

@CalumDouglas1

10 months

"Direct injection of petrol may prove to be an important step forward in the future. The carburettor is at best an amateurs method of mixing air with vapourised fuel." Chief of Air Staff correspondence 22nd February 1932 ----- Archive finds last week show that it was not just…

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Calum E. Douglas

@CalumDouglas1

8 months

Wartime Germany was not a good place to say what you thought, certainly not in upper management and above, but at the level of the engineers and aerodynamicists, many clearly felt able to say what they thought. Here, one aerodynamicist at the German DVL (German Aeronautical…

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Calum E. Douglas

@CalumDouglas1

9 months

When Sir Roy Fedden, probably Britain's most famous individual piston aero-engine designer - who had designed the Bristol Hercules and Centaurus sleeve-valve engines - was sent to Germany to investigate German wartime engineering efforts in 1945, his report berated the Air…

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Calum E. Douglas

@CalumDouglas1

7 months

I wrote this book over a period of six years which is now regarded as the standard work on WW2 aero engines, subsequently every F1 engine constructor except Honda has invited me to talk to their engine design engineers. Definitely do not buy it though, because its 450 pages long…

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Calum E. Douglas

@CalumDouglas1

10 months

During WW2 when Packard started manufacturing their version of the Rolls-Royce Merlin engines, certain differences were agreed as unfortunate but necessary. To deal with certain patent difficulties Packard made their own (quite different) supercharger gearbox system, and because…

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Calum E. Douglas

@CalumDouglas1

1 month

@historyinmemes Thirty years ago this speech would have been faintly amusing, now it’s hard to argue with most of that.

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Calum E. Douglas

@CalumDouglas1

8 months

Pro-Tip, if you are into your WW2 aircraft and feel a bit like dipping toes into more serious understanding of aerodynamics but get a bit put off by most aerodynamics textbooks, you need to buy this. As not only does it have nearly all the popular NACA profile shapes and test…

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Calum E. Douglas

@CalumDouglas1

1 year

Hated by the German Air Ministry more than ANY other Allied aircraft in WW2. Without equal, and unlike even the Spitfire, it was never plagued with obsolescence but always dwelled above the current competence curve. Until the turbojets, it was virtually immune.

Athol Forbes 🇺🇦

@Strangelyhappy

1 year

Into the night.... @WeHaveWaysPod #WeHaveWays

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Calum E. Douglas

@CalumDouglas1

7 months

All current Formula One engines use turbo compounding. This allows the thermal efficiency to reach 50%, an extraordinarily high level. Principally, this is achieved by recovering some of the huge waste exhaust heat into usable mechanical work, by, essentially - sticking a…

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Calum E. Douglas

@CalumDouglas1

7 months

The Spitfire started off as a ballet dancer, and ended up as a tavern thug. 450 mph and a ceiling of 44,000feet, Spitfire Mk8 with Griffon 65. It had a phenomenal climb rate, heavy armament and excellent dogfighting capabilities, you would probably not find any other piston…

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Calum E. Douglas

@CalumDouglas1

1 year

It was not without irony that when Beatrice Shilling helped the R.A.E. to overcome the negative-g Merlin engine cut-out problem in 1941 (work began in 1940 but was not applied in widespread use to Squadrons until 1941), there was sitting on a bench at Farnborough, the R.A.E.…

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Calum E. Douglas

@CalumDouglas1

3 months

Spitfire Mk21, it really was the end of the line for the airframe development, with so much more heat to reject from the high engine power the radiators grew to almost absurd proportions. They could not be sunk into the wing any more, could not be moved backwards and the duct…

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Calum E. Douglas

@CalumDouglas1

9 months

The matter of the magic "100 octane" fuel has reached the level of almost religious importance in Battle of Britain aviation "lore". Indeed it was extremely important, however... there was one...small...problem which is not often emphasized. The fuel didn't add any more oxygen,…

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Calum E. Douglas

@CalumDouglas1

4 months

And they say Germans have no sense of humour...

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Calum E. Douglas

@CalumDouglas1

1 year

None of the mystique surrounding the mosquito is hyperbole. It actually WAS superlative from introduction until the end of the war, only the Me262 had any success intercepting it (even then it was not a guarantee). Even Galland`s special Mosquito hunting unit was closed down,…

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Calum E. Douglas

@CalumDouglas1

7 months

@nationaltrust Definetly not any sort of casual vandalism. Some well equipped, knowledgable and capable people did this, and I would suggest were paid by someone. No way does a group of drunk trekkers go and "find" a very large chainsaw, make a huge amount of noise for 2 hours (which they…

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Calum E. Douglas

@CalumDouglas1

7 months

To all new followers, and indeed old, given the stupefying interest in my last tweet about Bomber command, there were a lot of questions about the Mosquito and if it could have been re-applied to secure a better solution to taking out Germany from the air than heavy bombers.…

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Calum E. Douglas

@CalumDouglas1

1 year

@aviationbrk Whats most weird isnt that some utter berk even did this, its the number of comments (ostensibly serious) saying things like "awww but noting bad happened why send him to jail?" If the abandoned plane had killed a father out hiking with his daughter, the same people would be no…

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Calum E. Douglas

@CalumDouglas1

7 months

Everyone* knows that WW2 piston engine supercharger science ended up in the first turbojets, but it is less appreciated that the technology swap also went in the other direction. Whittle, was, not just a quite exceptional system engineer, but was also in the opinion of several…

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Calum E. Douglas

@CalumDouglas1

2 months

Gears are like most parts of any high performance engine, on a basic level they`re just wheels with anti rotation teeth - but once you get into the detail, they become extremely complex, so much so, that a gear specialist once remarked to me that I might as well just resign…

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Calum E. Douglas

@CalumDouglas1

26 days

"9th February 1934, We have the honour to request the adaption of the type name "SPITFIRE".

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Calum E. Douglas

@CalumDouglas1

1 month

Someone designed that, with a pencil… Water cooled exhaust valve guides, variable geometry supercharger, crank nose oil feed, oil air centrifuge, direct injection… Happy Jumo 213 day everyone Night night!

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Calum E. Douglas

@CalumDouglas1

4 months

One of the most brilliant German engineers you`ve probably never heard of, Dr August Lichte. Lichte was in charge of the team who designed the Junkers Jumo 213 aero engine at Dessau. Without question the finest aero engine produced in Germany during WW2, it was in nearly every…

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Calum E. Douglas

@CalumDouglas1

11 months

Ceramic rocket engine rear cases under test in WW2 Germany. TU Braunschweig (University), December 1944. Materials shortages in Germany led to a lot of very early research into Ceramics for high-temperature applications. Much of the groundwork goes back to the 1920s in Berlin…

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Calum E. Douglas

@CalumDouglas1

8 months

The Messerschmitt Me 109 F was in my view the best all round version to enter service, relative to the opposing fighters. It was quite notably better than the Spitfire I, & II which it encountered in late 1940 and early 1941, but it was (like all German WW2 fighters)…

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Calum E. Douglas

@CalumDouglas1

8 months

I posted this about a year ago, after reading the RAF technical evaluation of a captured twin engine Bf 110 from the Battle of Britain. It caused me to have a moderate mental crisis for about a day, because (why was I surprised?) when you read the archive files, the stuff "WE ALL…

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Calum E. Douglas

@CalumDouglas1

5 months

Every engine has its own song, in fact a symphony of almost impossible complexity. Even without the deafening sound, the moving parts create myriad vibrations, of infinite orders, which send every part of the engine into song. Even the design of the bolts and studs are complex,…

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Calum E. Douglas

@CalumDouglas1

17 days

A decent propaganda article in Flight Magazine 1941, showing readers how much worse German fuel injection was than a float carburettor. In addition to such absurd statements as that the Merlin has 7 percent lower fuel consumption, it shows this terrifying picture of the fuel…

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Calum E. Douglas

@CalumDouglas1

2 months

So I was searching through the latest stack of archive papers when I found the original Packard report stating how long it took and how many people were needed to redraw the Merlin engine for their own production... ...Which was nice.

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Calum E. Douglas

@CalumDouglas1

15 days

Originally the Merlin WAS "hand built", because it had never been made in large volume before WW2 by anybody. So when Packard mass produced it, they were indeed justifiably proud as they took an engine which originally was hand-made and mass produced it. However, RR had already…

Twm Ford ( ; Autistic, ADHD, Depressed)

@fordlltwm

15 days

@DarkAdapted @habib_sammouh @guardpilot @CalumDouglas1 Packard certainly made a lot of what they did to mass produce it, how much is advertising and how much is accurate is an ongoing debate even today.

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Calum E. Douglas

@CalumDouglas1

1 year

@theJeremyVine I`ve been cycling all my life, and that was YOU looking for some "useful" video footage. What is disgraceful is you making an example of this style of riding to others. It goes against every principle of defensive riding, and to be frank, was also your fault. Go on a course.

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Calum E. Douglas

@CalumDouglas1

6 months

For those interested in what I like to talk about regarding WW2 aviation technology, I have several hours of footage online. The first video annoyed lots of people who said I was just criticizing the Germans for losing which isn't fair because I`m British and so I cant possibly…

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Calum E. Douglas

@CalumDouglas1

7 months

In the late 30`s the German success at high speed record attempts was getting a bit embarrassing for the RAF, who had been used to success sending their pilots to fly the Schneider Trophy racers until 1931 when the trophy was Britain`s permanently. A hotted up Spitfire called…

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Calum E. Douglas

@CalumDouglas1

5 months

People are generally so bombarded with wartime stuff in the media which is either "bang bang bang" or "gigantic industrial factories" that they never get exposed to the vast cleverness that is required in achieving the production. It took me a DAY to hand finish each of these…

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Calum E. Douglas

@CalumDouglas1

8 months

For all non-believers, resistance is futile! Wednesday 15th March 1943 – at Karinhall (MILCH Microfilm Vol-62 mf page #5505 …5508) Spoken word record from Stenographer: Goering: “I'm telling you directly, to just build the Mosquito!” Messerschmitt: “We can build more or less…

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Calum E. Douglas

@CalumDouglas1

7 days

Thats not a very holistic view of war, and only really applies if the enemy is bombing the wrong things, or with insufficient concentration. Once the Allies annihlated the German oil industry in 1944, virtually the entire German military infrastructure was immobilised in six…

Penguin

@habib_sammouh

7 days

@atallhill @CalumDouglas1 Not really. One can argue the effect of bombing endlessly, but eventually what matters is the frontline.

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Calum E. Douglas

@CalumDouglas1

1 year

The German Jumo004 WW2 turbojet which powered the Me262, really had no chance of any reliability. The prototype contained 130kg of Chromium, 88kg of Nickel. By the 10th June 1942, that had been reduced to 7.2 and 5.0kg respectively. A seventeen-fold decrease. It was doomed.

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Calum E. Douglas

@CalumDouglas1

5 months

This paper will help you on your journey from being an enthusiast, to a geek and then onwards to subliming to the "ultra-geek" level of WW2 aviation history. American engineers in 2020, writing a paper about an American engine from 1942, using a report found by a Scotsman in…

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Calum E. Douglas

@CalumDouglas1

5 months

All orders for my book on WW2 aero engines made through my own website before Christmas, will be supplied signed with a personalised message. You will learn the following: ➡️ Why Spitfires didn't have fuel injection in 1940. ➡️ How Nickel and Cobalt shortages dramatically…

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Calum E. Douglas

@CalumDouglas1

1 year

The Bf109 canopy is also awful with respect to aero, but unbelievably easy to make. Willy Messerschmitt knew all this, of course, and when it came to the racing planes obviously substituted more performance effective designs. Thats the 379mph Bf109 record plane cockpit of 1937,…

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Calum E. Douglas

@CalumDouglas1

9 months

The McDonnell XF-85 Goblin was supposed to sit inside a B-36 bomber to detach then re-attach when enemy fighters drew near, to avoid having to develop fighters which could possibly fly alongside the B-36 en-route. Sometimes you see a plane which makes you wonder how far down the…

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Calum E. Douglas

@CalumDouglas1

6 months

Yep. The 20 second answer is: Allied engines tended to last about 500 hours before major overhaul by the end of WW2, at the start it was perhaps 300 hours. German engines had similar service intervals in about 1939, but various serious problems meant that by 1944, a DB-605 from…

Tom

@t0mi51av

6 months

@CalumDouglas1 @nextlifer5 Can you share some info on producibility and maintainability/reliability of German, British and US WW2 aircraft?

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Calum E. Douglas

@CalumDouglas1

10 months

My third book! (well, half of a book) Dan and I had so much fun with THE SECRET HORSEPOWER RACE, and it sold so spectacularly well, that Dan suggested I help him with the engine side of a book on the Me309, a very enigmatic fighter - the story of which (when you ignore…

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Calum E. Douglas

@CalumDouglas1

3 months

Here, have a direct fuel injected Rolls-Royce Merlin. The pump looks a bit like a Junkers-Jumo direct injection pump, because... it is. The engine met the standard power output value for the carburettor Merlin, without any of the German injection system even being adjusted to…

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Calum E. Douglas

@CalumDouglas1

3 months

Hi @I_W_M - You have closed your Duxford archive to researchers, for years now, although it is still staffed. 1) Why is it closed to the public ? 2) When is it going to reopen ? People are having to cancel book projects because you are not making your archive records available.…

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Calum E. Douglas

@CalumDouglas1

7 months

The military designs we all know from the Second World War have long since become talismans of good or evil and have therefore, given up any chance of being properly understood. As a result popular understanding of how science and engineering actually work has been subverted.…

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Calum E. Douglas

@CalumDouglas1

7 days

For those interested in the German synthetic fuel industry, I have made a Google-map with the location and names of the fuel-from-coal Hydrogenation plants upon which the entire Luftwaffe depended (and many other areas too). Also included are the location of the ultra-critical…

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Calum E. Douglas

@CalumDouglas1

2 months

So serious was the negative-g carburettor problem, even after the application of the famous "restrictor", that Rolls-Royce and the SU company embarked on an emergency programme to develop a new carburettor. Rolls-Royce did most of the design work, occupying a significant portion…

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Calum E. Douglas

@CalumDouglas1

6 months

Britain could never have had a direct fuel injection system like the Germans had because it was far too complicated to make in Britain without all the precision machinery in Germany and .... oh wait. George Bulman`s comment (Air Ministry Director of Engine Development) stating…

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Calum E. Douglas

@CalumDouglas1

11 months

The Heinkel He177 was supposed to be a high performance long range WW2 bomber, by coupling together two standard engines, it was hoped at attain an aerodynamic advantage by eliminating two drag inducing bulky engine nacelles per plane. However, the engines were a disaster and…

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Calum E. Douglas

@CalumDouglas1

8 months

I present you with the Supermarine laminar flow wing (1943). "The aerofoil section gives a low drag range comparing favourably with the theoretical figure, and has a drag coefficient of the same magnitude as that of a normal aerofoil for climbing incidences" The Germans also…

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Calum E. Douglas

@CalumDouglas1

6 months

I always like finding SECRET wartime memos which clearly have bored scribbling all over them. This was one of the first meetings when Mallory was pushing his "Big Wing" philosophy. The ABWEHR naturally had a file on Mallory.... (which of course was in fact the opinion, not of…

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Calum E. Douglas

@CalumDouglas1

7 months

Everyone knows the story of the Defiant, an ill judged foray into the turret fighter concept. However, what is less appreciated is that the Defiant was very nearly not a small-scale experiment, in the mid 30`s and even right up until serious hostilities began, very senior people…

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Calum E. Douglas

@CalumDouglas1

10 months

NB, there is no evidence of duplicates or gaps in the airframe numbers in things like Bf109 production, so we can only conclude that at high level meetings, they were simply shown a list of how many new aircraft there were that month, you would in any case, never expect top level…

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Calum E. Douglas

@CalumDouglas1

6 months

Firmly in the "you CAN but you shouldn't" category. The world is full of "tuning shops" who regularly do this for the customer. In reality, this will get you a few more hours from the heads, but they`re basically scrap in the medium term. 1) You either weld it all up and…

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Calum E. Douglas

@CalumDouglas1

2 months

I`ve hoovered up about 500 new followers this week, so an introduction is in order. I`m a professional mechanical engineer, who usually works in F1 engines and small aircraft projects, and sometimes writes technical history books about WW2 aviation engines (two so far, the first…

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Calum E. Douglas

@CalumDouglas1

7 months

Redraw a WW2 fighter engine they said, it`ll be fun they said... Why make one radius when you can make FIVE, and put all the pivot points on different positions. No idea how they made 42,000 of these...

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Calum E. Douglas

@CalumDouglas1

11 months

German WW2 supercharger impellers were typically about three times lighter than Rolls-Royce versions (1kg vs 3kg), this did however bring about certain difficulties in that vibration was a more serious problem because the impeller was thinner. With NX software it looks like this

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Calum E. Douglas

@CalumDouglas1

9 months

The Me262 is so frustrating, so many differing accounts about who ordered what version and who was at fault for not getting it into service earlier, if only someone had just read the real archive files in German and ... oh wait they did.

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Calum E. Douglas

@CalumDouglas1

7 months

Casting patternmakers at work in about 1942 at Focke-Wulf plant. Generally, except for a few very specialist firms, almost nothing has changed in casting practise since these men were working on these moulds. An oversized pattern is made to account for shrinkage, and it is…

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Calum E. Douglas

@CalumDouglas1

8 months

More evidence of massive understanding even during the war of the efficacy of the Mosquito as a bomber over that of 4-engine heavies. The experience retention factor I had actually not considered. These statistics are stunning. (TOP SECRET, Deputy Chief of Air Staff, 27th April…

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Calum E. Douglas

@CalumDouglas1

6 months

"Why`s he always on about Nickel and exhaust valves ?" You say. Because you more or less cannot conduct a sucessful air war without them both in good order, and Germany didnt have them in good order. Its profoundly important for the course of the air-war in WW2, and had a…

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Calum E. Douglas

@CalumDouglas1

7 months

Oh I forgot that people cant read German. It says "[valve] Head coating after 70 hours, DB-603 [engine], Chrome Plated [LHS], Hard Coated [RHS]." Hard Coated in this case was an economy version of Stellite with less precious elements.

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Calum E. Douglas

@CalumDouglas1

2 months

@poneilexpress It appears not to have fallen off... so possibly some points are to be awarded.

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Calum E. Douglas

@CalumDouglas1

1 year

Typical WW2 aero engine development at Junkers-Jumo in Dessau. Here a Jumo V12 connecting rod is being developed to handle higher powers and speeds, a variety of techniques were used to analyse the stress, usually frozen photo-elastic results would be combined with stress-coat…

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Calum E. Douglas

@CalumDouglas1

8 months

Catastrophic impact on German morale in the Luftwaffe (especially night fighter pilots), pivotal role in pathfinding sucess and a long series of extremely effective low-level attacks on shipping and high profile military/political ground targets. No other aircraft of any type…

Rando42

@RandoRobby42

8 months

@CalumDouglas1 @SpitfireFilly I'm curious why you rate the Mosquito so high for war impact?

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Calum E. Douglas

@CalumDouglas1

9 months

The trouble with museums, and engines, is that they don't work as exhibits. On an aeroplane the primary functional surfaces are mostly external, but an engine is wrapped the wrong way, the outside is just about worthless as a visual guide. Leading to many, slightly inaccurate…

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Calum E. Douglas

@CalumDouglas1

7 months

That's absolutely bonkers, stats from the last 7 days. WW2 engineering history (in non-dumbed down format) appears to be alive and well.

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Calum E. Douglas

@CalumDouglas1

7 months

It is generally reported that at certain stages of the Battle of Britain the Hurricanes were sent after the Bombers and the Spitfires were sent on a different mission to engage the Bf 109`s. Usually no sources are given, so for those interested, here is one such source.

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Calum E. Douglas

@CalumDouglas1

1 month

In the 1930`s British and American fuel companies, sold complete plans to the Nazi`s on how to construct high octane synthetic aviation fuel plants, assisted in their construction, then helped insure the plants. Meanwhile some in the Air Ministry in Britain were hoping to get rid…

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Calum E. Douglas

@CalumDouglas1

7 months

Lets talk about Whittle and Powerjets Ltd from the perspective of an engineer (me) looking back at their work. Setting aside all the obvious stuff (that he was working on turbojets), there is something else which I find quite extraordinary about the technical papers of the…

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Calum E. Douglas

@CalumDouglas1

1 year

So precocious was the speed of the Mosquito that it was the only twin engine prop aircraft to be able to shoot down V1 pulsejets. Which it did, in considerable numbers (see kill statistics sheet below). Several squadrons of Mosquitos were employed to hunt "doodlebugs" along with…

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Calum E. Douglas

@CalumDouglas1

1 year

The more engineering from WW2 you read the more the myth of empirical development falls away like a rotten old net curtain. (build something, having no real idea how it works on the fundamental level, and improve it by making it smaller/lighter until things snap, then make that…

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Calum E. Douglas

@CalumDouglas1

3 months

After scouring what is I think the largest existing Allied repository of captured German wartime research, I can confirm: 1) No aliens 2) No flying saucers 3) No lasers 4) No Antarctic bases 5) No moon bases It was genuinely disappointing, but in the same way that its…

Tim Maher

@hathead82

3 months

@CalumDouglas1 Calum, I found your book enlightening, despite the material being largely over my head, but I’ll admit to being a little disappointed that you didn’t devote a full chapter to an in-depth analysis of Die Glocke.

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Calum E. Douglas

@CalumDouglas1

1 year

Its time for WW2 platitudes to die, they were only useful to mask our past ignorance. -German things are always over complicated ! -Air cooled radial engines are simple ! Below: A British air-cooled radial engine. (Hercules, German technical intelligence strip-down photo)

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Calum E. Douglas

@CalumDouglas1

3 months

I think the most purposeful ever photo of a Spitfire. (Clipped wing XIV with rocket installation, Boscombe down report stated that whilst a satisfactory platform for the rockets to launch from, the gigantic Griffon engine prevented sufficient forward view to allow the pilot to…

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Calum E. Douglas

@CalumDouglas1

5 months

How the FW-190 engine installation was tested. I’m order to balance between engine power, drag and exhaust thrust the entire assembly had to be mounted on a huge translating carriage in a full scale wind tunnel. The tests took one and a half years.

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Calum E. Douglas

@CalumDouglas1

1 year

@cctvidiots Truly magical.

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Calum E. Douglas

@CalumDouglas1

7 months

Look look see what arrived in the post.... Quite surprised how thick it is, nearly 500 pages, going to take me ages to read I`m afraid. I do like the first line of the introduction "I hadnt intended to write this book...." (Something I`m horribly familiar with)

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