His newest YouTube demonstration, though, might be even more impressive — it’s literally rocket science.
The “Hacker Extraordinaire,” whose day job is at video-game company Valve, built a small hybrid rocket engine from an acrylic rod that can throttle and also shut off. It’s the latest engineering project from Krasnow, who has nearly 3 million video views and 13,659 subscribers on his YouTube channel.
This rocket engine project is already his most-viewed video at 342,190 views in just four days. Here’s his explanation of the rocket engine:
I built a small rocket engine for demonstration purposes. The engine is built from a 2″ diameter acrylic rod through which I drilled a 0.5″ hole. The oxygen at 80 psi or less is passed through the hole and then is forced through a convergent-divergent nozzle at the tail end. The nozzle’s throat is about 0.25″ and expands to 0.625″. I lit the engine by inserting a burning cotton swab (with wooden stick) while a small amount of oxygen was flowing. The acrylic catches fire very easily in a pure oxygen environment. The engine can be throttled and shut off completely, which is a major benefit to hybrid engine designs. Solid-fuel rockets cannot be throttled or shut off, which makes them difficult to control.