大象传媒

Dan Snow investigates wake vortices, invisible spirals of air that trail behind aircraft. Pilots must avoid the wake vortices of other planes as they can be dangerous. An experiment at the German Aerospace Centre aims to uncover the invisible vortices and measure their strength. Test pilot Stefan shares what it鈥檚 like to fly into vortices left by another aircraft.

Wake vortices present a particular problem for busy airports like Heathrow. As planes get bigger, so do the vortices they generate. As a result the gap between landing planes must increase due to safety concerns. This places limits on the number of planes that can land over a given time period.