Pulse Jet Engine Blows Cold Air

When it comes to cool technology that seems to work by magic, a pulsejet engine is right up there at the top. With few or no moving parts, a pulse jet can actually create thrust! It uses a small propane tank for fuel, the jet can be throttled up or down simply by controlling the density of the fuel. For instance, if the tank has low pressure, the vapors will keep the pulse running at a low speed. Same goes for running up the pressure and you get an increase in output. Then, if you switch over to liquid propane by inverting the tank, the throttle will kick wide open.

If you just see the intense yellow-orange glow of the metal, you’d probably assume there’s nothing but scorching hot gas pouring out of those pipes. However, the YouTuber who built it says the exhaust is actually fairly cool at lower throttle levels. Obviously that changes as the throttle is ramped up and the metal heats up from one end to the other. You can see the throttle level swing back and forth rapidly when the propane tank is inverted and the fuel inside sloshes around, changing from liquid to vapor pretty quick.

When the fuel’s finally all gone, the flame burns out and the engine quiets down, it leaves nothing in place of the trademark pulse jet buzz. Have you seen a pulse jet firsthand? Did you have the same experience? We want to hear about it!