Regressive burning-(See Regressive granulation.)
Regressive granulation-With regressive granulation, the surface area of a grain decreases during burning. The burning
of a propellant with degressive granulation is termed "regressive burning" or sometimes "degressive burning".
Reliability-The probability of a device performing its purpose adequately for a period of time intended under the operating
conditions encountered. For a system with independent components, the overall reliability is based on the product
of the individual reliabilities; e.g., three components with a 90 percent reliability each will have an overall reliability
of 0.9 x 0.9 x 0.9 or 72.9 percent.
Remover-A stroking-type actuated device similar to a catapult, but usually of shorter stroke.
Sear-A component in the firing mechanism of a mechanically actuated propellant actuated device used to cock and
release the firing pin.
Single-base propellant-A propellant which contains only one explosive ingredient.
Single-perforated grain-A cylindrical propellant grain having a single perforation located along its axis.
Stroke-The distance the piston moves in a thruster or the sum of the motions of the tubes in a multitube propellant
actuated device (to the point where the system opens, if applicable).
Stroke time-The elapsed time between the first movement and the end of stroke of the stroking member of a propellant
actuated device.
Surface-time history-The relationship between burning rate of a propellant and pressure.
Thruster-A propellant actuated device designed to provide thrust for opening or closing latches, moving loads and the
like.
Web-In a grain propellant, the minimum thickness of the grain between any two adjacent surfaces. In designs of solid or
single-perforated grains, the propellant is entirely consumed when the web is burned through. In multiperforated
grains, this is not true, as "slivers" are formed at this stage which then burn to completion.
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