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The operational airspace of aerospace vehicles, including airplanes and unmanned aerial vehicles, is often restricted so that constraints on three-dimensional climbs, descents, and other maneuvers are necessary. In this paper, the problem of determining constrained, three-dimensional, minimum time-to-climb, and minimum fuel-to-climb trajectories for an aircraft in an airspace defined by a rectangular prism of arbitrary height is considered. The optimal control problem is transformed to a parameter optimization problem. Because a helical geometry appears to be a natural choice for climbing and descending trajectories subject to horizontal constraints, helical curves are chosen as starting trajectories. A procedure for solving the minimum time-to-climb and minimum fuel-to-climb problems by using the direct collocation and nonlinear programming methods including Chebyshev pseudospectral and Gauss pseudospectral discretization is discussed. Results obtained when different constraints are placed on airspace and state variables are presented to show their effect on the performance index. The question of 'optimality' of the numerical results is also considered.

The synthesis of actively controlled composite wings is reviewed by a new multidisciplinary optimization capability. The design optimization combined with techniques for the various disciplines is used for the nonlinear programming or approximation of the composite wing of a remotely piloted vehicle.

New methods used in the multidisciplinary design of airplane wings are given. Structural, aerodynamic and control system models are used to simulate a wing's behavior with computers. This optimizes the design with a precision that is good for a prototype. Nonlinear programming and approximation techniques are also used in optimizing the design. The analysis of the control augmented, aeroservoelastic, structural synthesis problems using the new methods are given with the results.

A multilevel decomposition-based optimization procedure achieves significant improvement in the aerodynamic and structural response of the high-speed proprotor blade in cruise, hover, and takeoff conditions. A nonlinear programing technique is employed at the upper level and a simulated annealing algorithm is used for discrete optimization at the lower level. The algorithm minimizes the tip displacements. The optimization results are compared with reference rotor distributions for chord, thickness-to-chord ratio, blade twist and zero-lift angle of attack.