The Learjet family began with the original six to eight seat Lear Jet 23 which first flew on October 7 1963. The diminutive Model 23 pioneered an entirely new market segment for the light business jets, and proved very successful.
The first production of these small aircraft was delivered in 1964 but it quickly became outdated as newer models were released throughout 1966 after many pilots requested a more powerful engine that could carry heavier loads than what existed at that time; this is how they developed into one of today’s most popular private jet charter flights available!