Plans face criticism from all over world, with vehement opposition to new rules covering trijets and quad-jets

The US Federal Aviation Administration is facing criticism over plans for updating rules on extended twin-engine operations (ETOPS). Boeing, the US Air Transport Association and the US Air Line Pilots Association are increasingly isolated in their support for the FAA's notice of proposed rulemaking (NPRM).

The strongest opposition is to the proposal that the ETOPS rules for twin-engined aircraft should also apply to trijet and quad-jet aircraft. But plenty of flak is directed at the intent to increase the ETOPS range of twin-engined aircraft from 180min single-engine flying time from usable diversion airfields to 240min or longer.

In practice, ETOPS rules only affect aircraft flying over the Pacific, the polar regions and other large areas of wilderness. But since the two big oceans and - increasingly - the North Pole and Siberia are much used routes, the issue is a live one. The FAA NPRM argues that modern twins such as Boeing's 767 and 777, equipped with additional systems redundancy, should be able to fly the unrestricted routes available to trijets and quads. It suggests trijets and quads should not be given extra advantages where additional onboard equipment and diversion rules are concerned, compared with rules governing twins. This has infuriated FedEx Express, Northwest Airlines, Singapore Airlines and others which have filed objections. They say that not only will "grandfather" rights be removed from a large number of trijets and quads, despite no evidence that this will improve safety, but that to meet the new rules will require costly additional systems redundancy not previously specified. Northwest says the FAA's NPRM "does not appear to reflect [the FAA's] intent as stated during ARAC [Aviation Rulemaking Advisory Committee] meetings".

Organisations like the International Air Crash Victims Families Group have filed vigorously against ETOPS extension for twins, as have groups as diverse as Airbus, the British Airline Pilots' Association and the European Joint Aviation Authorities. The JAA says it finds the FAA's NPRM imprecise in many of its claims on twinjet performance. The European agency makes clear that its own update proposal on ETOPS and extended long-range operations (LROPS) is "not fully completed", but that its notice of proposed amendment, when published, will differ radically from the FAA rule unless the NPRM is altered considerably before becoming a directive.

The National Air Transportation Association - the voice of US business aviation - is opposed because the NPRM would impose ETOPS rules on FAR Part 135 operators.

DAVID LEARMOUNT / LONDON

Source: Flight International