Equal time point (ETP)

Equal Time Point (ETP)

An Equal Time Point (ETP) is a specific location on a planned flight route where the total time required to return to the departure point is equal to the time needed to reach the point of intended arrival. Due to the influence of various factors like headwinds or tailwinds, the position of the ETP may differ along the route. It is an essential concept in aviation safety as pilots use it for contingency planning. If an airplane experiences an emergency, one can fly to the ETP in either direction and land at the nearest suitable airport rather than continuing with the original flight plan. A properly calculated ETP helps in determining the safest place to go in the event of an in-flight emergency, allowing the crew to make swift and appropriate decisions to handle any unforeseen situation.