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Hyper-X: Greased Lightning

The X-43A will use a rocket to help it reach supersonic speeds.
Image above: The X-43A Will Use a Rocket to Help it Reach Supersonic Speeds
How fast is the fastest plane in the world? The X-43 is the fastest plane without rocket power. It travels in what we call Mach speed. Mach is the speed of sound. The SR-71 Blackbird holds the record for fast flight at Mach 3. The X-43 will fly at speeds up to Mach 7. It is part of NASA's Hyper-X program.

Until now, the fastest planes have used rockets for power. Hyper-X planes are air-breathing jets. A turbojet engine has fan blades that force the air through the engine at high speeds. This creates the forward thrust. Rockets use fuel and oxygen that mix and burn to make thrust. Air-breathing planes have holes on the outside. They pull the air from outside. The plane's speed rams the air into the engine. This is why it is called a ramjet.

A drawing of the Hyper-X plane in flight.
Image above: A Drawing of the Hyper-X Plane in Flight
Ramjets are planes that use a stream of air to move forward at a supersonic speed. At hypersonic speeds, it's called a scramjet. Each jet has no moving parts in its engine. Air-breathing planes weigh less, too. They can carry more and still go fast.

NASA is testing the X-43A. It must be taken into the sky on a B-52 jet. When high enough, it is launched from a booster rocket. This helps it go fast enough for the scramjet to work.

The X-43C is like the X-43A but bigger. The X-43B won't need to be carried by a B-52. NASA keeps making the technology better!

Courtesy of NASA's Aerospace Technology Enterprise
Published by NASAexplores: May 30, 2002