In the 1950s, William P. Lear converted a Lockheed Model 18 Lodestar into a Learstar business aircraft. The idea was born that business travelers would no longer travel on scheduled flights. In 1963, the Learjet 23 appeared on the market as a twin-engine business aircraft with 4 passenger seats, which was widely imitated. Today, small, medium and large aircraft with varying degrees of luxury carry business travelers around the world.