A design-oriented model for the unsteady aerodynamics of a flapping wing has been developed using a modified strip theory approach. Within this constraint, vortex-wake effects are accounted for as well as partial leading edge suction and post stall behaviour. Also, the contributions of sectional mean angle of attack, camber, and friction drag are added, which allows this model to be used for the calculation of the average lift, as well as the thrust, power required, and propulsive efficiency of a flapping wing in equilibrium flight. An example of such calculations is presented in the performance prediction of a mechanical flying pterosaur replica.

The compressible flow Navier-Stokes equations, in conservation form, have been solved using a modified MacCormack implicit predictor-corrector scheme. For turbulent flow the solution is modified by incorporating an eddy viscosity, to solve the Reynolds-averaged Navier-Stokes equations. The algorithm is accurate to second order in time and space and is unconditionally stable. It requires the solution of block bidiagonal matrices and the programme can run on commonly available minicomputers. It also has the advantage that a steady state solution is approached, if it exists, independent of the time step employed.

Numerical results are presented for the two-dimensional shock-boundary layer interaction in both laminar and turbulent flow and the results are compared with experimental values and the numerical results of other workers. The method is calibrated against the analytical solution for the boundary layer on a flat plate and for the time dependent Couette flow problem.

After deriving the Stream Force Theorem, it is shown how this simplifies many problems of propulsion theory and makes the mathematics direct and concise. Applications discussed include forces upon ducting systems, intake entry losses, spill drag, mixing losses, errors in measuring intake losses by pitot traverse, and use of measured intake lip suction force in assessing entry losses and spill drag.

The preliminary design phase of an aircraft requires quick calculation methods to assess its performance. This note develops an analytical method to obtain the optimum range and associated flight parameters for a piston-prop aircraft. The aircraft is flying so that the altitude and airspeed are kept constant.

Such a flight is called “constant altitude-constant airspeed” flight or simply “constant h-V flight”. Transport aircraft generally utilise this type of flight profile. Such a profile has been analysed by Bert for turbojet aircraft, and Hale has discussed it for both turbojet and piston-prop aircraft. This note further improves the analysis of constant h-V flight by optimising it independently and without using the known values from any other flight profile.