For winch launching of gliders a winch cable cutter has to be installed, as a last safety backup should a glider not be able to unhook from the cable. When the Magalies Gliding Club build a winch, Diomedes designed, build and commissioned a set of two mirror image guillotines.

The energy for cutting is stored in a tension spring. Upon triggering, the spring swings an arm with heavy weights, which then shears the cables off once all the energy of the spring has been converted into kinetic energy. The triggering is done with a Bowden cable, which can with a small force collapse an over dead center lever mechanism. Reloading the guillotine is simply done by attaching a long extension to the lever and manually resetting it.

The guillotine must be able to instantly cut through three 5mm braided steel rope strands or three 3mm solid spring steel wires. It must also endure harsh outdoor conditions. Since the guillotine is a last resort life saving device a high level of reliability is required.

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The right hand Guillotine as 
mounted on the winch