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Australian Scramjet Launched
CaptainAlbert writes: "The University of Queensland, Australia is reporting the (possible) success of their "HyShot" scramjet test. The BBC have got this covered too. Apparently, they're now poring over the data loggers, trying to figure out if it actually flew under its own power." We had a story about these guys a while back.
The first German rocket scientists supposedly freaked out the same way you did, when they couldn't figure out why their guidance systems still left their rockets apparantly wobbling in all directions. It turned out not to be the guidance systems at all - just the wind. The rocket paths were straight, but shifting winds at different altitudes blew them into crazy lightning-strike looking things as the rocket was still aloft. I'd be surprised if the same phenomenon wasn't the explanation for that photo.
I bet it wouldn't be too hard to get that limit relaxed to something like no sonic booms below 15,000 feet (~4500m). A military plane once passed Mach 1 less than 2,000 feet (~600m) above the house of a friend of mine (at the time, he was living about forty miles west of Detroit in a rural area). He said it was really loud and shook the Earth, therein lies the problem. Moving it higher off the ground, is IMHO, a much better solution than an outright ban. In that regulatory environment, I can imagine the major hubs having regular supersonic connecting flights to each other, with conventional flights to all other airports. Think of it as a 'backbone network' for 'people packets'.
I like to play children's songs in minor keys.
"We're all sons of bitches now." --J. Robert Oppenheimer
many times
The US Space program used ordinary pencils in space throughout the Mercury and Gemini programs. Paul Fisher, founder of the Fisher Pen Company, spent over one million dollars of his own money developing the Fisher Space Pen before he came up with a working prototype in 1965, which he submitted to NASA for evaluation. NASA approved it for space flight in September 1965, and purchased 400 pens at $2.95 each in December 1967. The Soviet space program adopted them in 1968.
Why is it that the proponents of "one nation under God" are so eager to get rid of "liberty and justice for all"?
Accelerating at 1/10g (3.2 ft/sec/sec) to keep the passengers comfortable:
Mach 5 = 3000mph at high altitude = 4400 ft/sec
Time to reach this speed: 4400/3.2 = 1375 sec = 23 minutes
Distance covered while accelerating: 1/2(4400)(1375) = 3,025,000 feet = 573 miles
And your deceleration is going to be at least as long, so it's not worthwhile on trips much shorter than LA-NYC.
If the customers can be less comfortable, accelerate at 1g and your acceleration covers 57 miles in 137.5 seconds. But the ticket is going to be very expensive -- the plane has to go faster than most fighter jets BEFORE it can turn on the scramjets. So it needs ungodly big conventional engines, or else rockets. And the seats have to swivel around because you really don't want to hang from your seatbelt in 1g deceleration for 2 minutes.
Someone mentioned accelerating at 8g. This only takes 7 miles -- you could launch from an electromagnetic catapult to scramjet speed, IF the scramjets will run in thick air at low altitude. Of course, your passengers need a thorough physical, and there is still that deceleration issue.
Scramjets are not for airliners. The military applications should be obvious -- and you can use something like the space shuttle boosters in that case. Other than that, they might be useful for space launches -- get to Mach 5 with solid-fuel rockets, then use the scramjets to get to the outer fringes of the atmosphere at Mach 15 or so before you have to switch back to rockets. (The trouble with rockets is that they carry their own oxygen, which outweighs the fuel...)