Abstract
Small quantities of solid rocket motor propellant, of the type to launch the Space Shuttle, were burned at ambient pressure in the laboratory to provide aerosol samples for characterization. A portion of each sample was injected into an isothermal cloud chamber and the remainder into a 770 ℓ holding tank. Portable ice nucleus (IN) counters, filter devices for IN determinations and a cloud condensation nucleus (CCN) counter sampled from the tank.
The measurements show that particles resulting from the combustion of the propellant are active IN (3.3 × 108 to 1.5 × 1011 g−1 active at −20°C). The portable counters and filters detected significantly fewer IN than the isothermal cloud chamber. The propellant aerosol is a prolific source of CCN that swamped the instrument.
