One of my COVID projects with my 8-year-old grandson was building a Potato Cannon.....
Good times!
Firing at dusk you not only get the satisfying “thump” but also the flame shooting out the end......
The best I can tell we were getting three football fields in distance with Dollar General spray deodorant.....
When I was I high school I built one, but was unhappy with the need to constantly ventilate it to clear out the deoxygenated air. The answer, naturally, was to build an enhanced version with pressurized fuel (denatured alcohol) and oxygen injection, ignited by a spark gap inside the combustion chamber powered by a retrofitted stun gun. The whole thing was run by a microcontroller with fire control parameters entered on a laptop. A potato fired against a hard surface, like a concrete wall, would essentially turn into mist!