THE COMPOSITION OF SOLID PROPELLANT IN MODEL ROCKETS AND ITS EFFECT ON FLIGHT PERFORMANCE: A COMPARATIVE STUDY OF BIOMASS CATALYSIS AND GRAIN GEOMETRY

Abstract

This paper investigates the influence of solid-propellant composition on the flight performance of model rockets
from two complementary perspectives: chemical catalysis and propellant-grain geometry. The conventional potassium nitrate–
sugar (KNSU/KNSB) formulation is typically catalyzed with iron(III) oxide (Fe₂O₃); however, this study examines tobacco ash,
a low-cost, waste-derived biomass material containing calcium carbonate (CaCO₃), potassium carbonate (K₂CO₃), and trace
metal oxides, as a potentially resource-efficient alternative. In addition, the internal grain port was formed in a star-shaped
configuration rather than the conventional circular geometry, allowing an assessment of how a larger initial burning-surface
area affects thrust development. Experimental data obtained through static-fire testing and flight telemetry indicate that the
incorporation of tobacco ash was associated with higher measured burn-rate and specific-impulse values than those recorded
for the standard and Fe₂O₃-catalyzed formulations. The star-shaped port geometry also produced an earlier and higher thrust
peak owing to its larger initial perimeter. Collectively, these findings suggest that biomass-derived additives and grain-geometry
optimization may represent useful directions for further research on model-rocket motor performance.