Tuesday, March 31, 2009
You just shot my rocket into the neighbors' yard!
For Christmas, Chad gave Nimue a box of parts with which to build a bike pump powered rocket launcher which he saw written up in MAKE magazine, along with the promise to help her build it. The beauty of this system is that the rockets are cheap and easy to build (paper and tape), and don't require that you have rocket engines on hand, so you can shoot them off as often as you want. They've been working on building it on Tuesday nights when I'm off at rehearsal, and finished it off last Sunday.
The first test rocket was barely constructed and had not yet been decorated (fortunately, in retrospect), when Chad decided to test the whole apparatus out at low pressure in the back yard. He pumped it up to a mere 20 psi, and aimed it horizontally toward the shrubbery at the edge of the yard, thinking that it'd probably fizzle out across the grass, and if it didn't the camellia hedge would stop it.
20 psi. Recall that the rocket is made of paper reinforced with a little tape, and is therefore pretty lightweight.
PssshhhwhwhwhthhthhshhT!!!!!!!!!!!!!!!! [Insert maniacal laughter here]
Immediately after Chad hit the release valve, that little rocket tore off across the yard and straight through the bushes without even visibly slowing down. I peered over the fence into our elderly neighbors' yard, and didn't see any sign of it. It's entirely likely that it bypassed their yard entirely and ended up in the next yard down. Or the one after. At any rate, someone's day will be filled with some extra curiosity when they discover a little paper rocket stuck in their plants.
We obviously deemed the initial test a success, and after constructing a replacement rocket, headed over to the school field to do some vertical launches.
Also quite successful. A pressure of 40 psi will send the little rocket zinging up a couple hundred feet, and Nim had great fun chasing after it after it came back to earth.
After Chad wires in the remote trigger, we can try launching at higher pressure. I'll probably also experiment with making the rocket -- or at least the nosecone -- out of some squishy foam, as it clearly suffers a bit on landing...