Balcony Shoot #13 - Another Core-Burning Rocket

Date: 2003-10-14


Motor physically identical to last rocket, but with a different propellant.

I found this composition on Wouter Visser's website. He uses it in his helicopter/buzz-bomb devices. I thought it was worth a try as a rocket propellant:

68 Potassium Nitrate

14 Charcoal

9 Sulfur

9 Aluminium

The Aluminium and Charcoal mesh sizes were unspecified, so I used -200 mesh charcoal and -325 mesh spherical Aluminium. I ball milled the composition (sans the Aluminium) for only 30 minutes while I was assembling the previous rocket and cleaning up the mess I made screening charcoal. The Aluminium was then screened in with a few passes through a 60 mesh screen.

It is definitely cooler than my modified meal propellant, even if I ball milled it for hours I doubt it would be as hot. However it is fairly Aluminium rich and makes beautiful sparks and charcoal effects, kind of like a dense but short-lived firefly. It could be a polysulfide/Aluminium reaction causing the effect.

Standard stick (a longer non-red one) glued on. Fused with a meal-NC fuse using the same technique of a small quantity of propellant meal as a prime/passfire through the nozzle to make-do with the fatter fuse.


Very Nice Effect.

Clearly the cooler fuel makes for a more gentle take off and flight, but the tail effect is worth it. It is rather like a glitter comet, very attractive, especially near its apogee where is slows down and produces a dense cloud of long lasting charcoal effect and bright Aluminium sparks in the core.

Unfortunately the video didn't capture its most beautiful moments, near apogee and the first part of its fall. Wonderful stuff.

I doubt it could carry much of a payload, but the tail effect is worth a try by itself. It might work well in stingers, but I haven't made any tooling to try that yet. A larger end-burning driver would make a fantastic wheel, or maybe a nice driver for a girandola?

A longer core could compensate for its lower performance if you wanted the tail effect plus lifting capacity.


title type size
Launch Video video/x-msvideo 368.082 kbytes
Pre-Test Picture image/jpeg 22.799 kbytes