Various pyrotechnic compositions can be used, depending on the desired burn rate and required amount of energy and volume of gas produced. Some materials, such as
RDX,
sublime in vacuum, which limits their usefulness in aerospace applications. Composition with the character of
bipropellants and
flash powders are often used.
Standard pyrotechnic mixtures used by NASA •
Manganese /
barium chromate /
lead chromate: Time-delay mix, used for sequencing. Gasless burning. •
RDX /
nitrocellulose: Gas generator, unsuitable for deep space missions, burn rate dependent on pressure. Rapid pressure rise, little gas but emits hot particles, thermally stable, vacuum stable, long shelf life. Sensitive to static electricity. Known to cause circuit damage during ground testing. Sensitive to impact, friction, and static electricity. Thermally and vacuum stable, if
dextrin is not used for desensitizing. Long shelf life. •
Hexanitrostilbene: Used in detonators, linear
shaped charges, and bulk explosives. Insensitive to stimuli other than explosion. Thermally stable. Vacuum stable. Used in deep space applications where
RDX can not be utilized, such as aboard the
Apollo Lunar Module Detonates at . ==See also==