Lieutenant Commander Leland T. Lynch was an engineer aboard the USS Enterprise-D in 2364 under the command of Captain Jean-Luc Picard.
He supervised a realignment of the ship's dilithium crystals - an emergency procedure he had to perform manually when a shuttle carrying Counselor Deanna Troi crashed on the planet Vagra II.
Lynch had the strange habit of announcing his full name when answering or making a com call. Captain Picard demonstrated annoyance at this. (TNG: "Skin of Evil")