ETOPS

ETOPS is an aviation acronym for Extended Operation, according to the AC 120-42B. 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 were previously off-limits to twin-engined aircraft. (Aircraft produced after February 2015, ETOPS regulations extended for three, and four engines aircraft. The first time to the Boeing 747-8 Intercontinental quad-jet for examples built after that date.).

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 airfields, regardless as to whether such fields are separated by water or land.