The Learjet 60 is an improved version of the Learjet 55, with a longer fuselage and more powerful engines. It first flew in June 1991 and received FAA certification in January 1993
The modifications that converted the Learjet Model 55 into a Model 60 resulted from an aerodynamics improvement program and a need to increase the capacity of the Learjet product line. Several of these modifications were a first for Learjet. They include an all new inboard wing cuff added to the inboard sections of the "Longhorn" wing and an all new wing-to-body fairing. By increasing the wing chord and the leading edge droop, the wing cuff improved handling during approach and landing while the wing-to-body fairing reduced the interference drag between the wing and the fuselage. Since the engines were new for this aircraft, a new engine pylon had to be designed.
The lines of the cockpit have not changed but the fuselage was lengthened. In addition, the blend between the fuselage and the empennage was all new. While it appears as if area ruling was the intension of the blending, the blend design was really driven by attaching the original Learjet Model 35 empennage onto the larger Learjet Model 60 fuselage. An all new E/B (Emergency/Baggage) door was added to the right-hand side of the fuselage just at the leading edge of the wing.
The single ventral fin was replaced with two ventral fins that Learjet called "Delta Fins".
Production of the Learjet 60 ended in 2007 after 314 aircraft had been built.