Posted on 11/15/2004 11:24:28 AM PST by anonymoussierra
An "air-breathing" test plane will attempt to break a world speed record for the second time in a year by flying at nearly 10 times the speed of sound. Nasa's X-43A will use a revolutionary "scramjet" engine in an attempt to smash its previous mark of Mach 7.
While capable of reaching rocket-like speeds, it does not carry an oxidiser on board to ignite its hydrogen fuel; it gets its oxygen from the air.
The unmanned flight will take place over the Pacific Ocean on Monday.
Scramjet (supersonic combustion ramjet) technology could one day usher in a new generation of space propulsion systems.
"Nasa's goal has been to get to space more routinely and in a safer fashion," Joel Sitz, project manager for the X-43A, told the BBC News website.
Scramjets could be used to carry a spacecraft high into the atmosphere, after which a rocket would take over to propel the payload into space.
"We can't replace rockets, but we could use air from the atmosphere for two-thirds of the trip. That might give us the ability to carry bigger payloads for the same amount of money," Sitz added.
The X-43A is one of three planes built as part of Nasa's $230m (£124m) Hyper-X programme, described by the agency as "high-risk, high-payoff".
The first flight in June 2001 ended prematurely when the booster rocket veered off course and had to be destroyed. But the second, in March 2004, was a resounding success - setting a new aircraft speed record of Mach 6.83 (8,150km/h or 5,060mph).
This comfortably beat the previous record set by the Blackbird SR-71 spy plane which achieved Mach 3.2.
Final flight
Despite this, the future of US hypersonics research looks bleak. Plans to develop a larger hypersonic vehicle - the X-43C - were scrapped following President Bush's announcement in January that America would revive manned missions to the Moon by 2015 and attempt an expedition to Mars.
As a result, funding has been channelled into the development of a conventional rocket-powered vehicle, at the expense of longer-term programmes such as Hyper-X.
On 15 November, the third and final flight will take place over the Naval Air Warfare Center Weapons Division Sea Range.
At about 2100 GMT, a B52B aircraft will take off from Edwards Air Base in California, carrying the scramjet and its attached Pegasus booster rocket.
At an altitude of 12km (40,000ft) and a speed of Mach 0.8, the B52B will release the paired X-43A and booster.
The booster rocket will launch the X-43A to 33.5km (110,000ft) where the test plane separates from its booster. The aircraft then coasts for about five seconds in order to stabilise before igniting its engine and continuing under its own power.
The engine works by burning hydrogen fuel in a stream of supersonic air which is drawn in through a front inlet and compressed by the forward speed of the aircraft. Unlike a conventional jet engine, there are no rotating blades to compress the air.
The rapid expansion of hot air from the exhaust nozzle provides the engine with its thrust.
Getting fuel to ignite in a supersonic air stream has been likened to "striking a match in a hurricane"; so, successful combustion relies on controlling temperature and pressure within the engine.
The plane will be exposed to greater temperatures for the Mach 10 flight. So engineers have added a composite carbon thermal protection system to the plane's wing leading edge, its nose and vertical tail.
"On the nose, we expect to see temperatures of around 3,600F (1,980C). On the Mach 7 flight, they were closer to 2,000F (1,090C). Temperatures will be nearly twice as hot," said Joel Sitz.
Ocean dump
In addition to Nasa's programme, a group at the University of Queensland in Australia plans to conduct two Mach 8 flights and a Mach 10 flight in September 2005.
The Queensland team will test three separate scramjet configurations designed by the UK's QinetiQ company, the US Defense Advanced Research Projects Agency (Darpa) and the Japanese Aerospace Exploration Agency (Jaxa).
The US Air Force has a programme called HyTech, which is aimed at developing a hypersonic cruise missile.
The X-43A should travel about 1,370km (850 miles) before plunging into the Pacific. As with previous X-43A vehicles, it will not be recovered.
The attempt is the culmination of four decades' worth of work by different generations of scientists.
"The last X-43A flight did show evidence of thrust - something that people have sought since the 1960s," commented Professor Douglas Fletcher, of the department of aeronautics and aerospace at the Von Karman Institute in Belgium.
"It's nice for those people who have now retired to finally see the results of what they worked
ping NASA
What is "An "air-breathing"" Thank you
Not to rain on NASA's parade, but when I was in highschool, I had this 1974 Lincoln Continental, primer grey, and MAN THAT THING WAS FAST!!! In fact, one time, I made it from my place in South Philly to the Admiral Wilson Blvd in Jersey for a beer run in between the 2nd and 3rd periods of a Flyers game.
Now THAT'S fast!
" WAR IS PEACE
FREEDOM IS SLAVERY
DIVERSITY IS STRENGTH"
Air-Breathing plane?
Aircraft that requires air to operate. Propellors, jet turbines, ramjets, scramjets are all airbreathers.
Rockets are not.
Live TV coverage on NASA TV starting at 4:30 PM EST.
Thank you
Thank you :}}}}}
Thank you do NASA web show this.
Yep, your '74 Continental was fast, and to make matters worse, I've got NASA beat by Mach 0.8 for tens-of-millions less. Yes, that Mach 4 razor sure gives a close shave!
Is this the same thing as the mysterious AURORA plane that did or did not exist?
They were prepared to test a ramjet with the X-15; however, the program was cancelled prior to actually testing one. :-(
Thank you
Aurora - Top-Secret Hypersonic Spy PlaneThe outside world uses the name Aurora because a censor's slip let it appear below the SR-71 Blackbird and U-2 in the 1985 Pentagon budget request. Even if this was the actual name of the project, it would have by now been changed after being compromised in such a manner... On 6 March 1990, one of the United States Air Force's Lockheed SR-71 Blackbird spyplanes shattered the official air speed record from Los Angeles to Washington's Dulles Airport. There, a brief ceremony marked the end of the SR-71's operational career. Officially, the SR-71 was being retired to save the $200-$300 million a year it cost to operate the fleet. Some reporters were told the plane had been made redundant by sophisticated spy satellites... Lockheed's Skunk Works, now the Lockheed Advanced Development Company, is the most likely prime contractor for the Aurora aircraft. Throughout the 1980s, financial analysts concluded that Lockheed had been engaged in several large classified projects. However, they weren't able to identify enough of them to account for the company's income.
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