ETOPS

ETOPS stands for Extended-range Twin-engine Operations Performance Standards. It is a regulatory framework that allows airlines to fly long-distance routes over areas with limited or distant diversion airports using twin-engine aircraft. The rules were developed by the International Civil Aviation Organization and implemented by national authorities such as the Federal Aviation Administration and the European Union Aviation Safety Agency. ETOPS is designed to ensure that twin-engine aircraft can safely reach a suitable alternate airport in the event of an engine failure or other in-flight issue.

ETOPS ratings specify the maximum amount of time an aircraft may operate from the nearest suitable diversion airport. Historically, common limits were 60 minutes, 120 minutes, and 180 minutes. In recent years, some aircraft and routes have obtained approvals for longer diversions, up to about 330 minutes under strict conditions. These ratings depend on aircraft type, maintenance reliability, crew training, and operational procedures.

Operators must obtain ETOPS approval for each aircraft type and for the routes they intend to fly. Requirements include proven engine and airplane reliability, robust maintenance programs, dispatch reliability, diversion planning, fuel planning, weather considerations, and crew familiarization with abnormal procedures and alternates. Airlines must also demonstrate contingency capability and follow approved maintenance and inspection schedules.

The impact of ETOPS has been substantial, enabling twin-engine aircraft to perform long overwater and overland transoceanic flights that were once the domain of three- and four-engine aircraft. It continues to evolve with newer engine technologies, more reliable systems, and expanded route networks.