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X-43A Hits Mach 7
quiggy writes "As previously reported, NASA tested the X-43A yesterday. The results are in, and the scramjet hit Mach 7, setting a new speed record. CNN is also reporting the story, with a note that a similar jet could be tested by the end of the year, hopefully reaching Mach 10."
basically the higher you go, the less air there is, and the slower sound travels. So, the mach number, which is the ratio of your speed to the speed of sound, will be higher at high altitudes if the speed is constant.
It also could drastically cut the time of commercial flights -- perhaps shortening the trip between New York and London to less than five hours.
Considering Concorde did that in three hours, thit wouldn't be much achievement. I make it that it could do NY-LON in just over one hour.
What I think they should have said is that it could go from any point on the earth to any other, including the antipodes, in less than five hours.
Mind you, it would take three hours to get through security on departure and an hour on arrival to collect your baggage, if it had arrived with you.
Consciousness is an illusion caused by an excess of self consciousness.
Yeah, Pete Knight went to Mach 6.7 in Oct 67....STILL a record to this day, for a MANNED airplane (X-15 isn't "really" a traditional airplane since it is air launched). Also Pete Knight earned astronaut wings by flying the X15 near 300,000 feet. Several of the X15 pilots received astronaut wings by flying near or over 300,000 feet. Joe Walker, went the highest to 320,000 feet! Sadly, he was killed in the 60's when he was in a formation of planes for an Ad for the general electric engines that all the planes were flying. His "tiny" in comparison jet got too close to the XB-70 bomber (which was suppose to be a Mach 3+ bomber) and it went inverted and smashed into the tail of the bomber, and exploded. Sorry, the early years of test pilots, NASA has always fasinated me, and buddies of mine call me a walking encyclopedia of aircraft knowledge ;)
There's one fundamental difference between an ordinary jet engine and a scram jet engine: The Ramjet has no moving parts.
The all jet engines,operate according to Newton's Third Law of Motion:
For every action, there's an equal opposite reaction
The standard jet engine, invented by Sir Frank Whittle, sucks in air at the front. Then this air is mixed with fuel, and made to combust. The combustion causes the air to exit the engine at a velocity greater than when it came in, thus creating thrust. The escaping air causes the turbine to spin, and this intern activates the compressor, sucking more air in.
The Ramjet has no turbine and compressor unit. Ramjets fly supersonically and have an inlet which injests subsonic air after it goes through a shock wave in front of the inlet. The intake is slowed down aerodynamically, and then mixed with fuel and made to combust. But after about Mach 5, ramjets don't work so well.
The scramjet is almost but not quite entirely like a ramjet. The only difference being in a scramjet the combustion takes place as the air is travelling through the chamber at supersonic velocities.
More about the scram jet. Or another more concise explanation.
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Nothing to see here
It's not. This whole experiment is not at all about speed, and everything about a new engine design.
IIRC, Mach5 is the speed at which the scramjet is released, and ignited... up until then it's just being boosted by a conventional rocket.
During the first test, the scramjet failed.
During this test, it worked, pushing the rocket up another mach or two.
This was not meant to be any kind of speed record.. that's just how fast you need to go to get a scramjet working.
No, during the first test the rocket booster (the Pegasus) failed, mostly due to being released too low in the thick atmosphere. The entire package was destroyed by mission control before it went totally out of control.
Mach 10 is a record for powered flight; it is not even close to the record of a man-maned craft; IIRC that goes to the Apollo reentry capsules that routinely hit Mach 27 on re-entry. So the heat problem has been solved for quite a while.
The real problem here is that a scramjet engine is very sensitive to its input (the air coming in) as it only spends literally milliseconds in the combustion chamber. So you have to wonder what aerodynamic tricks the X-43A designers are pulling to smooth that flow before it goes into the intake. Notice the side-view of the aircraft; the belly is smooth and curvy in order to produce many small shocks ahead of the intake and slow down the air as much as possible. A terrific aerodynamic feat, I just have to wonder if it will be reproducible (i.e. stable enought and robust to any aerodynamic event) for a manned aircraft. [Yes, I am an aerodynamicist].
Let's sum it all up. 1) Escape velocity is IRRELEVANT in the discussion. That applies to unpowered vehicles - not a vehicle under constant power such as this one.
2) As has been already posted. The speed record isn't for ANY vehicle. The record is for a vehicle with an air breathing engine (ramjet, scramjet, etc). It doesn't apply to vehicles such as the X-15, Apollo capsules, the space shuttles, etc as their speeds were/are either rocket powered or unpowered reentry.
3) During the first test the scramjet engine did NOT fail. It was never even fired. The booster engine that was supposed to get the scramjet to mach 5 is what failed. If I remember right the fins or something fell off and it went out of control so the remote detonated the booster and consequently the scramjet testbed attached to it.
4) The toyota corolla attachment won't be out until 2006.
From cnn It is the first time a supersonic-combustion ramjet, or scramjet, which uses air for fuel, had traveled so fast, flight engineer Lawrence Huebner told reporters. The University of Queensland Launched the HYSHOT in July 2002. It Hit Mach 7.6. The first people who did this
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