Here are some photos and launch videos of my latest project, that was launched
on Saturday April 25th. The rocket is a boosted dart configuration. Booster
motor has a total impulse 10.700Ns (baby N), is 84mm in diameter and has a
filament winded fiberglass casing. Propellant is KN/Dextrose and the motor
burns for 2,6 seconds at 1300psi. Booster fins are made from aluminum and they
are TIG welded to a short piece of tube that gets screwed to the motor case
over the nozzle. Front end of the booster has a short piece of aluminum tube
which holds an altimeter, tracker , small parachute and a transition cone. Dart
is 37mm in diameter and it weighs almost 4 kilograms. Nosecone, boat tail, fin
can and fins are all made from a solid stainless steel. Dart fins are laser
welded to the fincan. Electronics used are PF Stratologger and ComSpec AT-2B in
the booster and PF Stratologger CF, PF MT4 timer and BRB 70cm GPS in the dart.
Theoretically booster and dart should be separated by aerodynamic forces at
burnout, however I didn't have any experience with this, that's why there was
also an auxiliary separation system in the dart boatail. This system was
triggered 0,2 seconds after booster burnout. Flight was successfull. Dart made
it to over 10,8km (35.400feet). Booster was recovered 1,5km away from the
launch pad, and the dart was recovered 2,7km from the launch pad.
https://www.youtube.com/watch?v=9vcAQPJUqV0
Andrej Vrbec
