What is ETOPS?
ETOPS is an acronym with several different but related meanings. Originally, it meant Extended Twin-engine Operations and referred to the operation of airliners with two engines beyond distances from potential diversion airfields which were normally permited by regulations. Typically, if an engine failed, a twin-engined airliner needed to be able to fly to a diversion airport on the single remaining engine and land within 60 minutes. The DC-9 and 737 could almost make it to many Caribbean destinations under the 60-minute rule, but not quite. Turbine (jet) engines are more reliable than piston engines, so the FAA and other agencies granted exemptions to allow these aircraft to fly up to 75 and the 85 minutes from airports. During the development of the Boeing 767 it was recognized that the aircraft was capable of long flights which would take it over more remote stretches of water than even the Caribbean 85-minute rule would allow. That led to the development of the first ETOPS rules, w
