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A new business jet is optimized to fly significantly faster than most current production aircraft while operating from relatively short runways. This new airplane is required to accommodate eight passengers in a double-club arrangement and to carry six passengers for 2800 n mile at a Mach number between 0.81-0.85. Two aircraft optimization codes are used here to ensure the validity of the design results and to identify errors in the analysis methods. These codes include the aircraft analysis methods necessary to evaluate the aircraft performance over an entire mission and optimization routines that enable the development of a family of optimum configurations. The design objective, empty weight, is shown to change approximately 1% between 30-40 deg of wing sweep at a Mach number of 0.81. At a fixed wing sweep of 31.5 deg and a Mach number of 0.81, the empty weight decreases less than 3.5% when the wing's thickness-to-chord ratio is increased from 0.10 to 0.14. A study of the design's sensitivity to Mach number indicated that the optimum empty weight and wing thickness began to change rapidly between the Mach numbers of 0.83-0.85.

The wing of the Learjet Model 60 was tailored for improved aerodynamic characteristics using the TRANAIR transonic full-potential computational fluid dynamics (CFD) code. A root leading edge glove and wing tip fairing were shaped to reduce shock strength, improve cruise drag and extend the buffet limit. The aerodynamic design was validated by wind tunnel test and flight test data.