Main Page | See live article | Alphabetical index A deflagration is a relatively slow explosion, generating only subsonic pressure waves. This sort of explosion is usually produced by rapid chemical combustion reactions, for instance of gunpowder in a firearm, or fuel in an internal combustion engine. Contrast detonation, where the pressure waves are supersonic. Deflagrations are easier to control than detonations, and better suited when the goal is to move an object (a bullet in a gun, or a piston in an engine) with the force of the expanding gas. This article is a stub. You can help Wikipedia by fixing it. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.