(OT) Tech stuff..
(I once had a trip around the USA's AMES research base, really quite impressed with all the toys they had there. I like reading up on the mars updates from JPL too. There is something Californian about playing in that big sandbox in the sky. The USA does some things really well, and thanks to Bob Dole we have the Internet too -g-)
jpl.nasa.gov
arc.nasa.gov
Nasa's Mach 7 technology
news.bbc.co.uk
The small X-43A separates from its booster at high altitude
The US space's experimental hypersonic research aircraft, the X-43A, could one day revolutionise long-distance travel.
The unpiloted 3.7m-long vehicle uses a scramjet to reach a design speed in excess of Mach 7, more than 8,000 km/h (5,000 mph).
Scramjets burn hydrogen but take their oxygen from the air which is forced into the engine at very high speed.
A scramjet operates by the supersonic combustion of fuel in a stream of air compressed by the high forward speed of the aircraft, as opposed to a normal jet engine, in which fan blades compress the air.
Click here to see the size of the X-43A
But scramjets only start to work at about Mach 6, or six times the speed of sound. And this means they first have to be boosted to their operational velocity.
In the case of the X-43A, this was done by a modified Pegasus rocket released from under the wing of a B-52 bomber.
The 1,300kg wedge-shaped research craft separated from its booster and accelerated away with the power from its scramjet.
The engine operated for just 10 seconds, after which the X-43A glided through the atmosphere conducting a series of aerodynamic manoeuvres for six minutes on its way to splashdown.
Saturday's test marked the first time a non-rocket, air-breathing scramjet engine has powered a vehicle in flight at hypersonic speeds.
Engineering challenge
Scramjet technology was first proposed in the 1950s and 60s. Because they take their oxidant from the atmosphere, the weight of any aircraft is therefore substantially reduced.
Those weight savings could be used to increase payload capacity, increase range or reduce vehicle size for the same payload.
TOP SPEEDS
Concorde: 1350mph (2173km/h)
Japan's bullet train: Record: 277mph (446km/h); scheduled service: 186mph (300km/h)
French TGV: World record (1990): 515.3km/h (320.3mph); scheduled service: 259.4km/h (161.1mph)
The scramjet attraction is obvious. If the many engineering challenges can be overcome, this propulsion technology could make it possible to fly, for example, from London to Sydney in just a couple of hours.
More likely in the first instance, they will find applications in the space delivery business - launching small payloads, such as communications satellites, into orbit.
The first-ever free flight of a scramjet was conducted by the US Defense Advanced Research Projects Agency (Darpa) in 2001. Its engine was fired from a gun in an enclosed facility on the ground.
A year later, University of Queensland researchers flew their HyShot scramjet on a missile |
