Minimum altitude‐loss soaring in a sinusoidal vertical wind distribution

Minimum altitude-loss flight of a sailplane through a given vertical wind distribution is discussed. The problem is posed as a non-linear optimalcontrol problem, and several numerical solutions are obtained using a gradient projection algorithm. The initial and final states are required to be equal, though they may be either fixed or free. An unexpected new optimal trajectory type is found to exist for relatively short ranges and free boundary conditions.