Destruct System and Radar Beacon Command Destruct
A destruct system was installed on the Scout vehicle to protect ground facilities and personnel outside the launching range from an errant vehicle if any failure should cause the vehicle to stray from its planned corridor. If a vehicle should stray beyond its flight path limits, radio signals from the ground would be sent to initiate the firing of explosive linear-shaped charges which would cut open the cases of the rocket motors. The motor cases would then be unable to contain the pressure of the burning propellant, and the motors could provide no thrust. The linear-shaped charge was an aluminum tube with a crimp formed along its length to form a “V”. The tube was filled with explosive powder. When the powder was ignited the aluminum metal in the “V” was vaporized and formed a directed stream of high-velocity molten metallic particles that would penetrate the motor housings. These shaped charges were installed inside the wiring tunnels on the first-, second-, and third-stage motors. Destruct of the fourth stage was not required because the altitude during its firing was too high for it to be a hazard to anything on the ground.
The radio receivers for the destruct system were located in the third stage. If for any reason the vehicle broke up and the first and/or second stage motors became separate from the third stage while the first- or second-stage motors were still burning, the radio command destruct system in the third stage would be unable to destroy these loose uncontrolled rockets. An auto destruct system was therefore used on the first and second stages. A wire lanyard secured to the upper stage was routed to a switch in the lower stage. If the stages separated the lanyard would be pulled out of the switch which would close and send firing currents to the EED’s in the destruct shaped charges. To prevent destruct of the lower stage during normal stage separation, a pressure switch that sensed motor pressure opened the auto destruct firing circuit when the rocket motor burned out.
Ground tracking stations tracked the vehicle with radar while it was in flight. Range safety personnel maintained a plot of vehicle while.it was in flight. Range safety personnel maintained a plot of the vehicle’s location and the limits of the corridor in which it was allowed to fly. They also knew the time it would take for the vehicle to travel from its present location to the corridor limits. If track of the vehicle was lost for this amount of time, range safety personnel assumed the vehicle was outside of its limits and sent a radio destruct command. It was therefore critical to the success of the launch that tracking was constantly maintained. For further safety over that provided by skin-tracking radar, Scout carried an active radar beacon to assure ground tracking. The beacon responded to a radio interrogation from the ground by transmitting a strong radio signal back to the ground. This signal was much stronger and more reliable than the weak skin-tracking radar signal reflected off the body of the vehicle.
SCOUT LAUNCH VEHICLE DESCRIPTION