Heinkels into German planes that crash Hurricanes -nsiderable quantities of alumance this country provide us wit mium, for every modern aeroplane is almost entirely built of aluminium or. rather, alumi ium alloys. Aluminium itself is too soft. explained H. F. James in the "Listener," it has io be mixed with small quantities of other metals to give t certain qualities such as hardness and strength. The result is alloys as strong as mild steel, but roughly a third of the weight, so you can imagine what a godsend aluminium was to the aircraft designer. In spite of its lightlies the average modern, single-seater fighter today contains about 14 tons, the average bomber about three or four tons, and in a flying boat you would get anything up to ten tons. Aluminium from crashed planes has to be cleaned, of course; you can't have a speck of dirt in the metal when it goes into the furnaces. But actually this is one of the easiest parts of the job. There are special cleaning methods and compounds for removing dirt, oil and other such substances. It is not true that German machines are badly made. Whatever you may think of their machines as compared With British, the stuff that goes into them is first-class, otherwise we shouldn't be so glad to get it as we are, Their alloys are much the same as ours, and only need cleaning and separating according to their composition—a process simple enough to us, though I suppose to the layman it is rather' a complicated process. The most interesting part of it is the w: the men identify the various metals and alloys, One way is by dropping a spot of chemical solution on the surface and watching it change colour; according to the change of colour, so you can tell what metals are in the alloy. As a matter of fact, we don't often need to use this test. We can identify the main alloys by their appearance, their position in the machine, and 50 forth. It we come across one that seems new to us, then a piece is snipped off and analyzed in the laboratory. Then, once we know what it ig, it's ready for melting down, and soon it's being rolled into sheets or bars to be built up into another Hurricane or Spitfire ready to shoot down more Heinkels or Messerschmitts.
Text read from the printed page and cleaned; old type leaves the occasional error.