Abstract : A technique has been developed for the design of maximum thrust three-dimensional (nonaxisymmetric) nozzles. The thrust expression, written as an integral over a control surface, is maximized by the application of the calculus of variations. Each optimal three-dimensional nozzle designed by this method produces the maximum axial thrust for a prescribed upstream flow field, mass flow rate, exit lip shape and position, and ambient pressure. Solutions for nine sample cases are presented. The performance of each optimal nozzle is compared with that of a three-dimensional nozzle with identical initial conditions and comparable overall dimensions. (Author)