Air Force set to fly Mach-6 scramjet
Air Force set date for first flight test of hypersonic jet
By Layer 8 on Fri, 05/21/10
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The US Air Force said it was looking to launch its 14-foot long X-51A Waverider on its first hypersonic flight test attempt May 25.
The unmanned X-51A is expected to fly autonomously for five minutes, after being released from a B-52 Stratofortress off the southern coast of California. The Waverider is powered by a supersonic combustion scramjet engine, and will accelerate to about Mach 6 as it climbs to nearly 70,000 feet. Once flying the X-51 will transmit vast amounts of data to ground stations about the flight, then splash down into the Pacific. There are no plans to recover the flight test vehicle, one of four built, the Air Force stated.
Hot space projects produce cool cosmic discoveries
"In those 300 seconds, we hope to learn more about hypersonic flight with a practical scramjet engine than all previous flight tests combined," said Charlie Brink, X-51A program manager with the Air Force Research Laboratory's Propulsion Directorate. Since scramjets are able to burn atmospheric oxygen, they don't need to carry large fuel tanks containing oxidizer like conventional rockets, and are being explored as a way to more efficiently launch payloads into orbit.
The longest previous hypersonic scramjet flight test performed by a NASA X-43 in 2004 was faster, but lasted only about 10 seconds and used less logistically supportable hydrogen fuel, the Air Force stated.
Hypersonic combustion generates intense heat and routing of the engine's own JP-7 fuel will help keep the engine operating properly, the Air Force stated. As the scramjet engine ignites it will initially burn a mix of ethylene and JP-7 jet fuel before switching exclusively to JP-7.
The Air Force describes the X-51 as virtually wingless, designed to ride its own shockwave. The heart of the system is its Pratt & Whitney Rocketdyne SJY61 scramjet engine, but other key technologies will be demonstrated including thermal protection systems materials, airframe and engine integration, and high-speed stability and control.
The Air Force said this will be the only hypersonic flight attempt this fiscal year, a change from the original test plan which was to fly in December 2009 then three more times in 2010.
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Air Force set date for first flight test of hypersonic jet
By Layer 8 on Fri, 05/21/10
Article Link
The US Air Force said it was looking to launch its 14-foot long X-51A Waverider on its first hypersonic flight test attempt May 25.
The unmanned X-51A is expected to fly autonomously for five minutes, after being released from a B-52 Stratofortress off the southern coast of California. The Waverider is powered by a supersonic combustion scramjet engine, and will accelerate to about Mach 6 as it climbs to nearly 70,000 feet. Once flying the X-51 will transmit vast amounts of data to ground stations about the flight, then splash down into the Pacific. There are no plans to recover the flight test vehicle, one of four built, the Air Force stated.
Hot space projects produce cool cosmic discoveries
"In those 300 seconds, we hope to learn more about hypersonic flight with a practical scramjet engine than all previous flight tests combined," said Charlie Brink, X-51A program manager with the Air Force Research Laboratory's Propulsion Directorate. Since scramjets are able to burn atmospheric oxygen, they don't need to carry large fuel tanks containing oxidizer like conventional rockets, and are being explored as a way to more efficiently launch payloads into orbit.
The longest previous hypersonic scramjet flight test performed by a NASA X-43 in 2004 was faster, but lasted only about 10 seconds and used less logistically supportable hydrogen fuel, the Air Force stated.
Hypersonic combustion generates intense heat and routing of the engine's own JP-7 fuel will help keep the engine operating properly, the Air Force stated. As the scramjet engine ignites it will initially burn a mix of ethylene and JP-7 jet fuel before switching exclusively to JP-7.
The Air Force describes the X-51 as virtually wingless, designed to ride its own shockwave. The heart of the system is its Pratt & Whitney Rocketdyne SJY61 scramjet engine, but other key technologies will be demonstrated including thermal protection systems materials, airframe and engine integration, and high-speed stability and control.
The Air Force said this will be the only hypersonic flight attempt this fiscal year, a change from the original test plan which was to fly in December 2009 then three more times in 2010.
More on link