Sensitivity analysis of the energy balance of dynamic soaring

Dynamic soaring is a periodic flying technique observed in large seabirds that enables the extraction of energy from wind and thereby facilitates covering large distances with minimum effort. It requires wind shears as seen close to the ocean surface or behind mountain ridges. At sufficiently strong winds it becomes feasible to extract at least the amount of energy required for overcoming the aircraft's dissipation. This situation is often referred to as energy-neutral dynamic soaring and would theoretically enable an abiding effortless flight. An energy-neutral dynamic soaring cycle has already been formulated and solved as a parametric optimal control problem. Due to the inherent variability of the wind, the sensitivity of the energy balance of an open type dynamic soaring cycle to wind conditions will be investigated within this work. Of particular interest is the wind direction and the wind speed. To expose the parameters with the strongest influence for some given conditions, state sensitivities will be computed after the optimization by applying the sensitivity differential equation approach.