A device attached to an aircraft control surface to discharge static electricity into the air. Static electricity builds up as air flows across the surface. If it were not discharged, it could build up high enough to cause a spark to jump between the surface and the main structure. Sparks of this type cause radio interference.

Some static dischargers use carbon-impregnated cotton wicks to pick up the static electricity and discharge it off the ends of the cotton fibers. Other dischargers have needle-sharp points from which the static electricity is discharged.