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USAF Hypersonic Scramjet Successfully Scrams
cold fjord writes "It looks like another milestone for hypersonic flight has been reached. From the story: 'The final flight of the X-51A Waverider test program has accomplished a breakthrough in the development of flight reaching Mach 5.1 over the Pacific Ocean . . ."It was a full mission success," said Charlie Brink, X-51A program manager for the Air Force Research Laboratory Aerospace Systems Directorate. The cruiser traveled over 230 nautical miles in just over six minutes over the Point Mugu Naval Air Warfare Center Sea Range. It was the longest of the four X-51A test flights and the longest air-breathing hypersonic flight ever. . . This was the last of four test vehicles originally conceived when the $300 million technology demonstration program began in 2004. The program objective was to prove the viability of air-breathing, high-speed scramjet propulsion. The X-51A is unique primarily due to its use of a hydrocarbon fuel in its supersonic combustion ramjet, or Scramjet, engine. ... The use of logistically supportable hydrocarbon fuel is widely considered vital for the practical application of hypersonic flight.'"
That's probably because they didn't have an effective bomber in that range.
Shall we speak of soldiers raping citizens and massive atrocities against prisoners of war or would you rather close the conversation now and accept your defeat? You're going to claim ethics and try to claim the moral high ground as a Russian? Really? Some of us know our history.
"So long and thanks for all the fish."
It's not quite space shuttle speeds. It's also worth mentioning that the engine block in your car has a melting point far below that of the combustion temperature of the fuel, but the heat is conducted away. Similarly a metal skin will allow conduction away from the surface for the heat to be dealt with elsewhere, and presumably a combination of low air pressure at high altitude (and thus lower frictional heating than at sea level) and relatively short fight times would mean the entire aircraft wouldn't have time to overheat before it gets to the destination.
It does mean however that carbon fibre reinforced plastic is probably a very bad idea for the skin while aluminium or titanium are going to conduct surface heat away at a rapid rate. There's going to be a lot of volume compared with the surface area of the leading edges so there's a lot of places for the heat to go.
I can tell you what happened at the Chinese companies, as I have seen this done before:
"We have a small order we don't really want, but we do not want to insult the person asking for the example by refusing outright. We'll send them something that looks terrible so they pick someone else".
Because frankly, 100.000 fluorescent fixtures is a tiny order for manufacturing that is going on Chinese scale right now. Most will simply not want to take it.