ETOPS - ETOPS Extensions

ETOPS Extensions

In 1988, the FAA amended the ETOPS regulation to allow the extension to a 180-minute diversion period subject to stringent technical and operational qualifications. This made 95% of the Earth's surface available to ETOPS flights. The first such flight was conducted in 1989. This set of regulations was subsequently adopted by the Joint Aviation Authorities (JAA), ICAO and other regulatory bodies.

In this manner the Boeing 737, 757 and 767 series and the Airbus A300-600, A310, A320 and A330 series were approved for ETOPS operations. The success of ETOPS aircraft like 767 and 777 killed the intercontinental trijets, and ultimately the Airbus A340. This ultimately led Boeing to end the MD-11 program a few years after Boeing's merger with McDonnell Douglas, as well as to scale down the production of its own Boeing 747.

The cornerstone of the ETOPS approach is the statistics that show that the turbine itself is an inherently reliable component, and it is the engine ancillaries that have a lower reliability rating. Therefore an engine for a modern twin jet airliner has twin sets of all ancillaries mounted in the engine, which gives the required reliability rating.

The North Atlantic airways are the most heavily used oceanic routes in the world. Most North Atlantic airways are covered by ETOPS 120-minute rules, removing the necessity of using 180-minute rules. However, some of the North Atlantic diversion airports, especially Kangerlussuaq Airport, are subject to adverse weather conditions making them unavailable for use. As the 180-minute rule is the upper limit, the JAA & FAA has given 15% extension to the 120-minute rules to deal with such contingencies, giving the ETOPS-138 (i.e. 138 minutes), thereby allowing ETOPS flights with such airports closed.

ETOPS-240 and beyond are now permitted on a case-by-case basis, with regulatory bodies in nations ranging from the USA, to Australia, to New Zealand adopting said regulatory extension. Authority is only granted to operators of two-engine airplanes between specific city pairs. The certificate holder must have been operating at 180-minute or greater ETOPS authority for at least 24 consecutive months, of which at least 12 consecutive months must be at 240-minute ETOPS authority with the airplane-engine combination in the application.