1510s, "one who steers a ship," from Middle French pillote (16c.), from Italian piloto, supposed to be an alteration of Old Italian pedoto, which usually is said to be from Medieval Greek *pedotes "rudder, helmsman," from Greek pedon "steering oar," related to pous (genitive podos) "foot" (see foot (n.)). Change of -d- to -l- in Latin ("Sabine -l-") parallels that in odor/olfactory; see lachrymose.
Sense extended 1848 to "one who controls a balloon," and 1907 to "one who flies an airplane." As an adjective, 1788 as "pertaining to a pilot;" from 1928 as "serving as a prototype." Thus the noun pilot meaning "pilot episode" (etc.), attested from 1962. Pilot light is from 1890.
Programmed Inquiry Learning Or Teaching. CAI language, many versions. "Guide to 8080 PILOT", J. Starkweather, Dr Dobb's J (Apr 1977).