What is a composite solid rocket propellant?
Basically, composite propellants are solid particles of oxidizer and fuel suspended in a binder. The binder is liquid when cast into the rocket chamber and sets up or cures to form a rubbery compound. The two most common oxidizers are ammonium perchlorate (AP) and ammonium nitrate (AN). A typical fuel for AP is aluminum powder while magnesium powder works best for AN. Regardless of what composite propellant is used, they burn in a very predictable way with respect to pressure, will not ignite from a spark, do not require working with molten ingredients and burn very slowly when not confined inside a rocket chamber.
