A design analysis is carried out to compare the performance of a telescoping wing airplane with a fixed-wing type. The increase in wing weight required by the telescoping wing is taken into account. Marked improvement in range performance is obtained with the telescoping wing. Optimum design values of cruise velocity are obtained for each landing speed. A preliminary design of an 8-place turbofan amphibian aircraft is carried out to show the relation of component weights to a fixed-wing design. Performance of the example aircraft is marginal.