The kill switch is installed between the bare terminal on the magneto block and the engine block. You can use a simple SPST (single pole/single throw) toggle from Radio Shack. When the switch is in the open position, the engine runs. When it's closed, it grounds the primary side of the coil, killing the engine. This switch is highly recommended when running a gasser, since they can fire any time the prop is turned. If you will fly in IMAA-sanctioned events, a kill switch is mandatory.

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