this looks safe

[duc_fan]

alfisti beat me to it... it's definitely a pulse-jet.  As soon as I heard the sound I thought of the V1.

[Slide Panda]

My 1st thought was a messed up ramjet - but yeah it's a reconstituted buzz-bomb engine.

[JDucati]

Pulse jet... easy to make too

[NAKID]

those propane canisters are pretty much bomb proof these days.

the buttmake the beast with two backss at the columbine massacre tried to detonate them and couldn't.  the valve has a safety cutoff inside and the skin of the canister is absurdly strong -- i've seen 50 bmg rounds go thru them but nothing less.

very slick video though!  me likey!

[Rameses]

That looks like something Rameses and Jobu put together in their garage 

We haven't made it that large-scale yet.   

[eichh]

Man my neighbors would be totally pissed if I bought one of those. So is that basically a giant propane powered saxophone?

[Big Troubled Bear]

Very safe, when you wear the right gear