Did I mention I build and fly rockets? This is Super Bonbon, my L1 high power rocketry cert flight, launching in the Mojave Desert in the summer of 2021.
@JBrianCoyle @emma Nice! Hybrid engines always sounded cool but hard, is it tricky to time the NO2 and ignition? Or can that be pretty reliable as long as you have the right stuff/knowledge?
I played with 3 engine clusters a bit, getting all 3 to fire simultaneously took a some effort.
Hybrids are a bit more complicated (one reason why I like'm), but not difficult. A big issue (especially in Florida summer) is maintaining cool bottle temp. Otherwise the density causes poor/degraded performance.
Timing ignition isn't an issue as long as you can see the venting (look left/above the gold band in my pic)
Clusters *require* high current - best with a relay/battery at the pad. Clip whip = friend
I’m thankful the clubs I fly with use relays at the pad/cell. It’s essential for high power rocketry’s requirements for launcher distance from the flight line.
For a cluster, I’ve built a four 18mm engine kit from Klima to get experience with clusters (the Andromedia) before trying it with bigger motors.
@JBrianCoyle @emma Ok, seeing the venting makes sense, I was interested because it was complicated as well but never quite got there.
For clusters I was launching with a lawn tractor battery (lead acid, about 1/2 a car starter battery) but the relay is a good idea. I used the sturdiest speaker wire I could find, but that did probably limit the current quite a bit. I was worried about following the letter of the regulations and avoided fully arming anything while still at the pad.