This seems to be the week for aviation news. Yesterday I wrote about the first flight across the continental United States of a solar-powered airplane. Today it’s time for something completely different: the successful final flight of the X-51A Waverider hypersonic aircraft, which took place last Wednesday, May 1.
The Waverider aircraft — a joint project of Boeing, the Air Force Research Laboratory, DARPA (Defense Advanced Research Projects Agency), and Pratt & Whitney Rocketdyne — is basically a test-bed for hypersonic engine technology. In particular, the scramjet engine.
Hypersonic flight involves going faster than Mach 5. Mach 5 is five times faster than the speed of sound. The speed of sound is about 760 mph. So, that means flying faster than 3,800 miles per hour. Faster than 1 mile per second.
That is what the Waverider accomplished. The unmanned aircraft flew for a total of about 6 minutes and hit Mach 5.1, tearing a hypersonic hole in the atmosphere as it did so. This was the longest scramjet-powered flight ever.
The project’s primary stakeholders, as you might imagine, are proud of the success they achieved this week. You may have heard more about hypersonic flight in the last few days than you can remember hearing for years, perhaps since the heyday of the rocket-powered X-15, which still holds the official record for the fastest powered manned aircraft (4,520 mph in 1967).
A scramjet (short for “supersonic combustion ramjet”) is a jet engine that utilizes oxygen compressed at supersonic speeds to combust jet fuel. The exhaust velocity translates to insane levels of thrust. A scramjet engine has no moving parts. One of the advantages of a scramjet engine over a rocket engine is that it doesn’t have to carry oxygen to burn with the fuel. A rocket must carry its own oxygen supply along with (usually) hydrogen rocket fuel, adding weight. A scramjet engine uses the oxygen from the air.
And it burns jet fuel. That is, basically, gasoline.
So, you’ve got a gasoline-powered vehicle flying at Mach 5. The ultimate goal of scramjet technology is to produce aircraft capable of flying at speeds of Mach 10 to Mach 20. That translates to aircraft that can fly across the Atlantic Ocean in about an hour, from takeoff to landing. And also fly into the lower regions of outer space.
The X-51A Waverider resembles a cross between a torpedo and a surfboard. It’s called the Waverider because it rides its own shockwave, taking advantage of compression lift effects.
The Air Force is very interested in the Waverider aircraft technology. Why? Cruise missiles. A cruise missile traveling at better than Mach 10 can blow the hell out of something a lot faster than current missile technology allows.
Last Wednesday the X-51A was carried aloft from the Air Force Test Center at Edwards Air Force Base under the wing of a B-52H Stratofortress. It was released at approximately 50,000 feet and accelerated to Mach 4.8 in 26 seconds, powered by a solid-fuel rocket booster. After separating from the booster, the 14-foot-long Waverider’s scramjet engine then lit and accelerated to Mach 5.1 at 60,000 feet.
After exhausting its 240-second fuel supply, the vehicle splashed down in the ocean and was destroyed as intended. 370 seconds of telemetry data was collected from the experimental flight.
But what does all this rather dry data translate to? It means that we are building aircraft capable of going faster than a speeding bullet — much faster than a rifle bullet.
Of course, I wrote yesterday about an aircraft powered only by the sun. If I had to choose, I think I’d say the solar-powered plane is cooler than the scramjet-powered X-51A. Still, the Waverider flies about 100 times faster than the Solar Impulse. There is that. I appreciate “fast” as much as the next guy.
On the other hand, this is an airplane that requires fossil fuel. Which , you know, is getting more expensive at the pump.
But as long as we have jet fuel, in about 20 years we may be flying from L.A. to New York in an hour.
Who gets to do projects like this?
Of course, I say “we” are building aircraft faster than a speeding bullet, but when you come right down to it, only a few guys get to play with this level of technology. Only a few of the very smartest get to work on projects like this. You know what we call them? Engineers.
Hey, if you feel like you might want to be given hundreds of millions of dollars to develop things like hypersonic aircraft, then you’ve got to learn some things. You’ll probably need a degree in aerospace engineering or mechanical engineering or programming. You also have to be creative enough to solve technical problems that no one has ever solved before. Then you can build something extremely cool.
You can be like the guys in the video below. Or like the designers of the Solar Impulse airplane.
Want to learn more about technology and develop your skills? Start by exploring the books and materials at InformIT, one of the best online repositories of information and instruction relating to high-tech engineering and programming.
Maybe you can be one of those guys who helps develop the Mach 20 planes. Or flies one.
The sky’s the limit. Or not…