Comments by "John Burns" (@johnburns4017) on "Curious Droid"
channel.
-
47
-
22
-
19
-
16
-
15
-
13
-
13
-
12
-
11
-
11
-
10
-
8
-
8
-
8
-
8
-
7
-
7
-
7
-
7
-
7
-
7
-
7
-
7
-
6
-
6
-
6
-
6
-
@standriggs2420
The Mustang was basically a British plane made by an American manufacturer for them. The British Air Ministry directed a six year old inexperienced company, North American Aviation, to the design points they wanted for their plane. British engineers assisted North American who drew it up, as a university lecturer would do in directing students to research various points in a project. The students run off do the research with the lecturer assessing what they did and how it fits into the project as a whole. The Mustang was a British plane made by an American company for them. There was no US forces involvement in the concept, specifications or design. Many Americans lose sight of these fundamental points.
The Rolls Royce Merlin engine made the Mustang perform superbly. The plane initially used an Allison engine, which was only good at low level, as RR could not meet the supply of Merlins at the time, so the Alison it had to be. The US were behind the British in engine supercharging with the Tizard Mission giving the USA details of advanced super charging. Also the cylinder head design of the Alison was not good enough for full supercharging. Stanley Hooker of RR developed the auto controlled twin-speed twin-charger supercharging technology which was given free to the USA. The first use of the Mustang by the US military was for ground attack because of the poor high level performance of the Allison engine.
https://www.youtube.com/watch?v=by4lH2whhjk
In the early stages of WW2, the U.S. government allowed the British & French to by-pass them, allowing direct approaches to U.S. aircraft makers, as would the British government approach say Hawker. The British needed all types of planes urgently, even the P-40 which was inferior to their own front line planes. But warplanes they were, being useful in certain theatres and for training.
In early February 1940 the British asked North American Aviation's President Dutch Kindelberger to supply P-40s made under licence from Curtiss, as Curtiss could not supply demand. Unlike Curtiss, North American's factory was far from operating at capacity. Kindelberger told the British, "I can build you a better airplane, and I can get it built fast". Contrary to popular belief in the USA, North American did not have a prototype ready design which the Brits just happened to have snapped up under the noses of the US military. The design was developed over many months with British engineers at the British Air MInistry's office in New York.
North American were first approached in Feb 1940, who had no "detailed drawings or plans". The British gave this young inexperienced company a chance but they would have to hold their hands. In May 1940 as France was falling, North American still never presented any detailed plans, mailing a design concept drawings to the British delegation in New York. This never had the famed laminar flow wings. After back and forth, the Air Ministry accepted the design starting the Mustang project. The British Air Ministry accepted the inferior Allison engine as Rolls Royce were working flat out 24/7 unable to meet demand for Merlins. New Merlin factories were being set up but not yet fully on-line.
In the interim from Feb to May, three months, the British Air Ministry were forming the fundamentals of the design concepts directing North American to Curtiss and NACA the developer of the laminar flow wings, to ensure a fighter with some leading edge design points, not produce another P-40 fly-alike wasting valuable time. The Air Ministry directed NAA to the Curtiss XP-46 experimental plane with all the leading edge design points of top European designs, with a few of their own, rolled into one.
NAA were ordered by the British Air Ministry to buy the plans and test results of the XP-46 plane from Curtiss and study them as they had never built a fighter, if they wanted the job, at a whopping $56,000, a lot of money at the time. Curtiss engineers always said the Mustang was their design. Not quite as the British Air Ministry had a lot to say in the leading design points - they were paying and calling the shots as it was their plane. There was a danger the Mustang may end up the same way as the XP-46 - a plane with leading edge points that never performed as expected in one package. The British Air Ministry took a major gamble with NAA so were active in approving the emerging design points.
The Ministry wanted something better than the poor P-40, being prepared to wait, but realistically never expected Spitfire performance. Initially that was the case with the first deliveries using the Allison engine - better than a P-40 but no Spitfire. The initial Allison engined Mustangs filled an RAF niche, so no problems for the British at that point. A niche the plane filled was that the RAF needed a long range reconnaissance plane that could also perform ground attack being able as a low level fighter if the need was there. The Spitfire was a short range fast interceptor. With the fall of France the RAF needed a plane with range to penetrate over the German border from English air bases.
Reading many US books on the Mustang you would think the concept of the plane was to escort US bombers. That is fanciful. The last thing the British Air Ministry were thinking of when laying down the points of the plane was US bomber doctrine. The US were not even in the war. Initially the US military overall didn't want to know the plane. The Mustang was not even in U.S. service when it was shooting down FW-190s by the RAF over France. The Air Ministry gave the U.S. military two planes which were left in the corner of a hangar for a long period, initially not assessing it. Quite amazing, as the USA never had a decent front line fighter at the time.
The excuse not to take up the plane by U.S. forces was that it was liquid cooled and vulnerable in frontal attack. This was a poor excuse to reject the plane because it wasn't theirs. What went over their heads was that the world's two best fighters locked horns in the Battle of Britain, both with liquid cooled engines. With British support, the Mustang finally was noticed by the U.S. Army Air Force. The US military had to go to England to fully assess the plane as it was finished off in Liverpool being flow by the RAF. They did eventually adopt the Mustang calling it the Apache and P-51 when in U.S. service.
UK and U.S. Mustangs for the European war theatre were finished off in Liverpool. They were test flown then delivered to the units by young English girls, many of them teenagers. The Mustang was built to British specification and design guidance without a doubt. They specified and paid for it. It never performed at all like the short range interceptor the Spitfire, not having the manoeuvrability of the Spitfire. It was 'fine' and reasonably fast at low altitude with the Allison engine. It could operate over France and even Germany at a push, escorting bombers because of the longer range that the British Air Ministry specified. The Mustang filled a niche role for the British. continued......
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
5
-
4
-
4
-
4
-
4
-
4
-
....Continued...
North American were not working on installing a Merlin engine before Rolls Royce. Rolls engineers under Ron Harker went to North American to advise on what to do. They also gave advice from their work with the RR Mustang X. Rolls-Royce made the first proposal to North American about a Merlin 45 engine Mustang in 1940, after Stanley Hooker improved the power by 30%. This was before the plane was operational an still in the R&D stage. The RR Merlin now was greatly superior to the Alison engine, to what it was in February 1940 when North American were approached by the Air Ministry. The later Merlin 61 had the two-stage auto controlled supercharging developed again by Stanley Hooker. This gave an extra 70 mph and 15,000 feet of operation to the Merlin. A quantum leap. The pilot just went where he liked without degradation in performance.
RR sent three engineers led by James Ellor to supervise the adaption and manufacture of a Packard built Merlin 61, the same type that was already being considered for the Rolls Royce Mustang X experimental series. https://en.wikipedia.org/wiki/Rolls-Royce_Mustang_Mk.X
On 9 June 1942, the first memos from W/C I.R. Campell-Orde of the RAF Air Fighting Development Unit at Duxford, reveal that an effort was being made to convince North American to adopt a Merlin-powered Mustang. Work in the US was setback due to an initial lack of interest and also to mechanical failures of the first Merlin engines built under licence by Packard. Both projects commenced at nearly the same time with the first Mustang X in the air about a month earlier than the North American XP-51B.
The RR Mustang-X programme was 5 or 6 airframes each with different experimentation. RR attempted to have North American accept British Merlin 61s (the two-stage superchargers) in American airframes, it is clear that the prime contractor (NAA) wanted to control the project as control was looking like it was to move over to the UK. NAA was essentially building production-standard aircraft rather than the experimental series that saw each of the RR Mustang Xs trying out new variations of design. An offshoot was the mid-engine RR Griffon engined Mustang that actually made it to the mock-up stage, albeit with a Merlin installed amidships. On the success of the RR Mustang-X built in Nottingham, the Air Ministry ordered hundreds from RR, who declined wanting to remain specialising in engines. NAA remained the prime contractor.
Rolls Royce mass produced Merlins in Crewe, Manchester and Glasgow, licensing Packard in the USA to make them supplying the Canadian aircraft factories - to avoid a two-way trans-Atlantic trip using idle US industry. An agreement was reached in September 1940, with the first Packard built Merlin engine running in August 1941.
Early in 1944 the P-38, P-51B Mustang and P-47C, were dived by the British for compressibility testing at the RAE Farnborough, England at the request of the USAAF. They had trouble when these planes dived onto attacking German fighters when providing top cover for the bombers. The results were that the Mach numbers, the manoeuvring limits, were Mach 0.68 for the P-38, Mach 0.71 for the P-47, and Mach 0.78 for the Mustang. The corresponding figures for the FW-190 and Me109 was Mach 0.75. The tests resulted in the Mustang being chosen for all escort duties.
- Page 70, Wings On My Sleeve by Eric Brown, who did the test.
4
-
4
-
@myrtistaylor5759
He does not go into great detail. That is the idea, it is an overview. He does explain that a transistor can be:
1) An amplifier of a signal - making the signal stronger as it passes through. An example is that a weak radio signal can be made stronger to power a speaker.
2) A gate. A gate is just that, it stops the signal, as a light switch does, or allows the signal to go through, as a light switch does. Using it as a gate it is a relay. One circuit switches on and off another.
As the gate is either on or off, it is ideal for the binary numbering system which is 0 and 1 (base 2). We use in our everyday use base 10 because we have 10 fingers. This is a cumbersome way of using an electronic component as a device is switching on and off a signal, not having it continuous and moving all the way fast as in an analogue form - electricity moves at approx' 1,860 miles per second. It is inefficiently stopping and starting.
But here is what makes it feasible. Having 60 billion transistors in a device that can carry out two billion on and off switches per second, binary calculations can be performed amazingly quickly.
How does that make a modern digital electronic device work? A computer, computes, constantly calculating. That is what it is doing underneath. The so-called computer devices we use, the function is not computing for the end user - using a web browser on a smart phone is not adding up numbers. To achieve what the end user wants, an amazing level of calculations are performed underneath using the binary, base 2 system. All performed by the Central Processor Unit (CPU) and other components that contain transistors used as gates.
4
-
4
-
4
-
4
-
4
-
4
-
4