Investigations into landing and takeoff in a downburst are made with a simple wind model based on the flow toward a flat plate. Approaches along a given nominal glide path are analyzed. The influence of the changing wind on the aircraft's demand for energy is calculated. The results are given in energy height errors. Computer simulations of an aircraft with fixed controls show the well-known flight-path pattern of accidents in manual flight. As far as the demand for energy is concerned, approaching through a downburst is not a problem. This can be pointed out by computer simulations with a modern autopilot and autothrottle control system. The energy situation of an aircraft in a downburst is more dangerous for takeoff than for landing. Heavy thunderstorms can produce wind conditions under which a takeoff is not possible. Gentle downbursts can be crossed by a simple escape maneuver. The acquired knowledge of landing and takeoff in a downburst contains some important aspects for the go-around.