Damn! I obviously went to the wrong school...I'm building one for the end of our dock to counter the jetski's and speeding boats...its a bit more sophisticated though and I plan on using cocoanuts...

While y'all are working on your physics how about backing up to a little spelling?!
Or is that a "Britain" thing?

NICE Bear!!!!!!!

Yah, 'tis! The duty on cases of engine starter propellant is going to eat me alive Marty, but maybe I can get a neighbourhood(sic) watch to help underwrite a "shore battery".

I'm also working up an air burst version of the cocoanut(sic) shell to counter low flying aircraft. I do forsee a problem in that there may be a lot more "stuff" floating around in the water once I perfect that round...

Proud to say the "engineer" that built this project is my Son!!!!! He is the guy wearing the cap!!!!!!!

Wow! Just saw this one! WAY TO GO WILLIAM!!! Very cool school project.

My son built one of these about 10 years or so ago. It was a lot of fun but I was worried we where all going to get arrested especially one night firing it off into the woods from my rear deck. At night a flame would come out the barrel a few feet and it was louder than it seemed in that video. The potato would go about 100 yards or more. We used an igniter like you use for a Gas BBQ grill. Hair spray was the propellant.

I tell you one thing it you ever got hit with the potato you would be a hurtin puppy.