Njaco
The Pop-Tart Whisperer
another bit I believe is that the first 109 had a British engine and the last version, built by Spain, also had a British engine.
Wasn't the Erla hood a somewhat copy of the bubble canopies used by the Britiah and USA?
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Spain also built 109s and He-111s. In an interesting bit of irony, the Israelis had some of the Czech 109s.
Metallurgy was "borrowed" from the British by the Russians. Read an account where Russians were given a tour of a British jet engine factory, and they wore soft soled shoes that would pick up metal shavings. The shavings were analyzed back in Russia to figure out the ingredients in the alloys the British were using and having success with in their jet engine program.
T-44 and later Soviet tanks copied torsion bar suspension from the German Panzer Mk III, Panzer Mk V and Panzer Mk VI.
Germany was working on a wire guided air to air missile which didn't quite make it into production. Post-war France produced the missile in modified form as an anti-tank weapon.
The post-war French SNECMA Atar jet engine was derived from the BMW003 engine.
Not terribly difficult to reverse engineer.
But figuring out the alloys was the hard part - all that had to be done "by hand." Melting the samples gathered and figuring out the alloying elements without the help of complicated machines and computers, that was the challenge, and I'm sure many of the engineers assigned to do this task worked under duress.the soviets did have the advantage that once they analyzed a metal sample they could order a metal supply factory to produce that exact alloy without worrying about trade secrets or proprietory alloys.
Different British suppliers had slightly different alloys, some of which worked better than others in certain applications or needed slightly different heat treatment to get the same performance.
things got better in the 50s-60s.
I'd like to know where you got that information from or what specific parts, materials and their alloy specifications we're talking about. When a component is designed a specific material specification is called out on the engineering drawings and within that material specification is the alloying requirements. For example, if a component was to be made from 7075, it doesn't matter if the aluminum is bought from Reynolds or Alcola, 7075 is going to be made from "5.1-6.1% zinc, 2.1-2.9% magnesium, 1.2-2.0% copper, and less than half a percent of silicon, iron, manganese, titanium, chromium, and other metals"
The British would do the same on some of their earlier material specs for turbine engines and the only major difference you're going to find is the amount of impurities that may be in the raw state of the material. Using my example of 7075, as long as the ingot meets the basic alloying requirement for the spec, it doesn't really matter what supplier the material comes from.
I believe that is correctdid the British "spec" 7075 aluminium or did they "spec" something like "B.B. 111" As in Bermabright 111?
See: iii | flight advertisements | ill birmabright | 1944 | 1049 | Flight Archive
or: flight advertisements | hiduminium applications | aluminium alloys | 1944 | 2487 | Flight Archive
Again it depends what was being ordered and what was being produced. Usually machine shops were given the material to machine and also given limited detail of what they were 'cutting.' If the material was eating up (for example) routers, then manufacturing engineers would talk to the machinists about speeds, feed times and cooling.The British were into proprietary alloys. Now another supplier might be able to supply the same thing or maybe not unless they paid royalties to the first company?
Hard to say but also consider costsRemember Bristol tried over 40 alloys and hundreds of heat treatments and manufacturing processes to get the sleeve of the sleeve valve to stay round. It took a bit of high level coercion to get them to share this knowledge with Napier when Napier ran into trouble with their sleeves.
Many British companies had small engineering staffs and sometimes relied upon suppliers to suggest or recommend special alloys for specific applications.
Sometimes they didn't know why something worked, they only knew that it did and if they tried substituting something else it failed.
Most, if not all Bristol Hercules engines used imported Swedish roller bearings on their crankshafts. No British supplier could meet Bristols standards? or there was something about the Swedish bearings that was different but not readily identifiable?
I'd like to hear about more substantiation of this - I do know in the US, before the AF allowed a pilot to strap himself into a new aircraft, there are AF engineers who want to know how the thing was put together and what it was made from.There is a story about one of the Shadow factories tooling up to produce aero engines. The Car manufacturer who ran this plant wanted to "Buy British" when it came to the machine tools but the parent plant insisted on Swiss gear cutters for the reduction gears. Finially it was decided to try the British gear cutter on a trial bases before buying the majority of machines. The trail set of gears failed about 70-80 hours into the standard British type test. The way the two different gear cutters worked stressed the gear teeth differently as they were being cut.
BTW, I didn't dream this up on my own. I believe the proprietary alloys thing was mentioned by Herschel Smith in his book "A History of Aircraft Piston Engines" but perhaps he was wrong and I am seeing things that were not there.
Perhaps - the war years produced things out of necessity and need. In the later years processes were refined to mitigate risk, today that risk mitigation is pounded into design teams with risk assessment requirements.The British aero industry and it's suppliers may have been very different in the 1940s (both during the war and right after) than they were in the 1950-60s or even later.
Material; I once saw a TV documentary in which an ex-automobile engineer saying that when Toyota or Nissan started to manufacture automobiles after the war, they found themself even couldn't copy just a piece of leaf spring taken out from a US made jeep, which actually had been shot peened. The material composition could have been analysed or purchased, but it is evident that type of material treatment wasn't known to us then.
Hard to say but also consider costs
The mechanical properties would be listed in the manufactures data sheets. For special duties (connecting rods, piston rings, valve seats or even turbine blades or discs it is probably a question of the engine maker asking one or more suppliers what they have or would recommend for the job specified. After trying one or more samples/suggestions from each supplier one alloy is selected for use. Subject to further testing or service use.I'd like to hear about more substantiation of this - I do know in the US, before the AF allowed a pilot to strap himself into a new aircraft, there are AF engineers who want to know how the thing was put together and what it was made from.
Perhaps - the war years produced things out of necessity and need. In the later years processes were refined to mitigate risk, today that risk mitigation is pounded into design teams with risk assessment requirements.
With all this said, it goes back to my original point about the Soviets reverse engineering Nene engines. Not an easy undertaking and actually in a sense an engineering marvel, even though they weren't the original designers.
That's more the exception than the rule. Having seen this as a prime contractor and from a sub-tier I can tell you that most of the time the prime contractor has those issues worked out, however I have seen items manufactured where the subcontractor presented evidence that the part could be made better or was even impossible to make and the prime made the necessary changes.The mechanical properties would be listed in the manufactures data sheets. For special duties (connecting rods, piston rings, valve seats or even turbine blades or discs it is probably a question of the engine maker asking one or more suppliers what they have or would recommend for the job specified. After trying one or more samples/suggestions from each supplier one alloy is selected for use. Subject to further testing or service use.
Actually when raw material is purchased by say an engine manufacturer for critical applications, not only does the material supplier supply material certifications, but must also supply "coupon" testing and results for the material and sometimes the prime may do their own analysis for verification.I think that samples would be supplied for testing, to confirm manufacturers specifications. as in "super alloy XXX" has a tensile strength of "YYY" when heat treated so and so. Other properties would also be given in the metal manufacturer's specification data and testing done to confirm these properties. What they might not tell people is the EXACT alloy percentages.
Because depending on the applications, some "allowed" impurities can cause problems down the line. For example, in wrought 7075 ingots, you would not want a high silicon content for something that going to be continually exposed to a salt environment.As long as the production stock meets the original specs and passes quality control checks why should the government care if Alloy "XXX" has .25% more of one element than Alloy "ZZZ" from another company?
They did then and in some cases they do in today's worldIf alloy "XXX" is doing the job needed and there is enough of it the British might not have cared that much about a second source except in the case of bomb damage to the supplier. The government may have been controlling the flow of raw materials in any case.
No but the argument lies in some proprietary processing that a manufacturer may be reluctant in sharing with the government. During my years at lockheed I seen this on several occasions.These materials are not total unknowns and the government is not allowing engines/aircraft to be built with materials that are untested., as in "trust us, you don't need to know the yield strength, or bending strength or wear characteristics of our alloy, we say it will do the job and that should be good enough for you"
TrueNo disagreement on this point. While the Soviets can certainly order any alloy they decide on (from analyzing the sample engines or shavings) without having to pay royalties, getting the heat treatment and other manufacturing processes correct is going to be quite a trick.
Some wartime contractors couldn't do even with help from the parent factory.