Another drawing of the United Tech UA-1205 solid rocket motor. This depicts the forward end of the motor including the closure, the igniter and the booster separation motor structure. Everything here could, with relatively little effort, be compared closely with the Space Shuttle Reusable Solid Rocket Motors. The RSRMs were entirely new designs, but the design concepts were by and large taken from the UA-1205.
Not depicted here are the thrust termination ports that the earliest motors had. These ports were a feature designed in due to the fact that the Titan IIIC was originally designed to be a manned launch vehicle (for the Dyna Soar program). In the event of an abort after launch, the ports would be blown out by way of externally mounted linear shaped charges; the ports would provide escape paths for the pressurized gas in the motors. These would not only provide thrust to counteract the thrust coming out the nozzle at the aft, but the sudden increase in port area would mean that the chamber pressure would plummet. And as chamber pressure plummeted, the propellant burn rate would also plummet. Combustion could have been completely stopped, depending upon conditions; in any event, the motors would cease to provide meaningful thrust in a split second and could be safely jettisoned… or the manned portion could eject without fear of being run over by the boosters.
