Scramjet stands for Supersonic Combustion Ramjet. Scramjet is a type of air propulsion that uses the free air in the atmosphere with onboard fuel such as hydrogen and methane to propel an aerospace vehicle. Some people refer to the actual vehicle type as scramjets or air-breathers.

How do Scramjets work?

Scramjet Picture

The air is scooped from the atmosphere and enters the opening at the front of the vehicle. The air enters at very high speed. The air slows once it enters the combustion section and is compressed by the forward speed of the aircraft itself. Fuel is injected in the airflow.

On August 16, 2002, the University of Queensland in Australia completed the first successful flight of a scramjet vehicle, reaching speeds of Mach 7 or seven times the speed of sound.

Possible Uses

The Scramjet can be used for military purposes. For example, to replace the B-2A bomber. It could also be used for cheaper access to space using a vehicle similar in concept to Ronald Reagan’s Orient Express vision. It has been used in the X-43. Past potential Russian designs it was going to be used was the Tu-2000 and Mig-2000.

List of Vehicles above Mach 3:

Ramjet propelled / Air-breathing vehicles that flew faster than mach 3.3 achieved by the SR-71.

France: DEFA/ONERA NA 250 (M3.4), SE 4400 (M3.7), Nord ST 450 (3.8), Nord Vega (M4.3), Onera Stataltex (M5)

Russia: La-350 Burya (M3.43), Vichnevetsky 036 Vikhr (M3.5), Zvezda AS-17/Kh-31 (M3.5), Fakel V-757 (M3.7), Tchelomei SS-N-19 (M4), Fakel V-758 (M4.8), Tsiam Kholod (M5.6, first scramjet).

USA: UTC Spark (M3.5), Lockheed GTD-21 (M4.3), Lockheed X-7 (M4.3)

UK: Sea Dart (first seaplane to reach supersonic speed)

Did you know?

The study of Scramjets is hypersonics.

Books and other Merchandise:

Scramjet Propulsion (Progress in Astronautics and Aeronautics, Vol 189) from

Hypersonic Airbreathing Propulsion/Book and Disk (Aiaa Education) from

Scramjet Links:

NASA: What’s a Scramjet?
HyShot – Centre for Hypersonics: The University of Queensland:
The Langley Combustion-Heated Scramjet Test Facility Brochure:
Commissioning of Scramjet Combustor Flight Experiment: from Japan Aerospace Exploration Agency

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