Pulsed Detonation Engine

Long-EZ Pulsed Detonation Engine Aircraft

The Long E-Z aircraft, powered by the pulsed detonation engine, makes its history-making flight Jan. 31 at Mohave, Calif. Soon it will be on display at the National Museum of the U.S. Air Force at Wright-Patterson Air Force Base, Ohio.

I was familiar with the concept of the pulsed detonation engine but had no idea that a project was underway. This was a proof of concept aircraft. The engine was built with off-the-shelf automotive parts.

What makes the PDE so unique is instead of burning fuel, called deflagration, to get propulsion, air and fuel are mixed, ignited and detonated in controlled explosions inside open-ended tubes that look like exhaust pipes. When detonation moves through the tubes, it creates a supersonic shockwave that continually pulses and generates thrust.

The increased thrust could be capable of powering future aircraft up to speeds of Mach 4, or four times the speed of sound, and beyond. The PDE can be combined with other engine cycles, such as turbines, rockets, or hypersonic scramjets, to optimize flight envelopes, said Fred Schauer, assigned to the AFRL Propulsion Directorate.

I have no idea whatsoever what the next step (if there is a next step) will be.


  1. If I’m not mistaken, this is what powered the V-1 in WWII. The distinctive noise it made due to it’s propulsion is why they called it the ‘buzz bomb’.

  2. You’re correct SwissFreek the V-1 used a pulsejet enjine. Although this article refers to a Pulsed Detonation engine and that seems to be different than the Pulsejet. I was under the mistaken idea that the V-1 was powered by a Ramjet, but as you can see by the following article I pulled off the internet is a bird of a different feather. Pulsejets have been around since the 1940’s, and were used as the propulsion system of the German Fiesler Fi-103, better known as the V-1 Flying Bomb. The V-1 used an Argus Pulsejet which produced about 300 kilograms of thrust, and had a pulse frequency of around 47 Hz. In order to get sufficient air through the Argus Pulsejet, the V-1 had to be accelerated up a ramp by means of a steam catapult, powered by T-Stoff (Hydrogen Peroxide) and Z-Stoff (Calcium or Sodium aqueous solution used as a catalyst for the Hydrogen Peroxide). The Argus Pulsejet was also used in other German aircraft such as the Messerschmitt Me-328. Ramjets and Pulsejets are often confused, but they are actually quite different types of propulsion. Whereas a pulsejet is reliant on a valve system to mix and ignite the air/fuel mix before combustion and subsequent ejection – all as a series of pulses, a ramjet is a very simple device which literally consists of an intake, combustion and nozzle system in which the cycle pressure rise is achieved purely by ram compression. Consequently a separate propulsion system is needed to accelerate the vehicle to speeds at which the ramjet can takeover. A ramjet is literally just a tube into which fuel is continually fed and ignited. The ramjet does not use a pulsed mode of combustion, but rather continuous combustion.

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