A portrait of William P. Lear, Sr. (1902-1978), chairman of the board of Lear Jet Industries, Inc. An American inventor and businessman, Lear developed radio direction finders, autopilots, and the first fully automatic aircraft landing system. Lear also developed and marketed a line of panel-mounted radios for General Aviation. His "LearAvian" series of portable radios, which incorporated radio direction finder circuits as well as broadcast band coverage, were especially popular. Lear also developed the 8-track cartridge, which was an audio tape system popular in the 1960s and 1970s. He is best known for founding the Lear Jet Corporation, which manufactured business jets in Wichita, Kansas. In 1990, Lear Jet was acquired by Bombardier Aerospace.