ETOPS

ETOPS is an aviation acronym for Extended Operations. The term used to signify Extended Range Operation with Two-Engine Airplanes but the meaning was changed by the US Federal Aviation Administration (FAA) when regulations were broadened to include aircraft with more than two engines. It refers to the standards and recommended practices (SARPS) issued by ICAO for aircraft (such as the Airbus A300, A310, A320, A330 and A350, the Boeing 737, 757, 767, 777, 787, the Embraer E-Jets, and the ATR 72) to fly long-distance routes that had been off-limits to twin-engined aircraft, and subsequently to extended range operations of four-engined aircraft (such as the Boeing 747-8 Intercontinental).

In aviation vernacular, the colloquial backronym is "Engines Turn Or Passengers Swim", referring to the inevitable emergency water landing of a twin engine aircraft after a double engine failure over water outside gliding range of land. But ETOPS operation has no direct correlation to water or distance over water. It refers to flight times between diversion airports, regardless as to whether such fields are separated by water or land.

There are different levels of ETOPS certification, each allowing aircraft to fly on routes that are a certain amount of single-engine flying time away from the nearest suitable airport. For example, if an aircraft is certified for 180 minutes, it is permitted to fly any route not more than 180 minutes single-engine flying time to the nearest suitable airport.

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