Precautionary landing

To keep the passengers and crew safe, an aircraft experiencing a technical defect or other problem may need to land as quickly as possible.

To keep the passengers and crew safe, an aircraft experiencing a technical defect or other problem may need to land as quickly as possible.

In practice, they most often return to their point of departure and make what is known as a precautionary landing. As the name implies, this is a safeguard rather than an absolute necessity. In most cases the problem is not serious enough to endanger the flight, but pilots – like air traffic controllers – do not take unnecessary risks. As soon as a something goes awry, they contact air traffic control to report the issue. Sometimes the cause is an external one such as a tail strike (the tail of the plane touches the ground during take-off) or a bird strike (birds hit the plane, also usually during take-off). But technical problems are more common: an engine or communication systems defect, say, or a partial loss of cabin pressure (decompression). Upon receiving a report of this kind, air traffic control assists the pilot in any way it can and facilitates a precautionary landing on his or her preferred runway. The reason the pilot can request a particular runway is that only he or she knows what manoeuvres the aircraft is still capable of making. Moreover, the pilot at all times remains responsible for the aircraft and for landing it safely. Air traffic control makes sure that its separation from other aircraft is maintained, to prevent possible conflicts.