Guy Norris/LOS ANGELES
Boeing is proposing to raise the standard 180min extended range twin engine operations (ETOPS) restriction to 207min. The objective is to allow Boeing 777s on some transpacific services to take an optimum routeing which would save up to 30min flying time.
"It is the operators which will technically be going to the [US Federal Aviation Administration] for approval, not us," says Boeing, adding: "We don't really anticipate approval until late this year, or early 1999." The FAA's Seattle office confirms it has been consulted by Boeing, and that, "-if a proposal is submitted, the FAA will establish an appropriate means to review it".
Boeing says the extension, a 15% (27min) increase to the existing limits, will close a geographical gap where aircraft would be more than the maximum allowable 180min single-engined flying time from the nearest diversion airport on some North Pacific routes. The company says that the gap exists only if all North Pacific diversion airports "-simultaneously do not meet minimum weather requirements for ETOPS route planning, or if there is volcanic activity".
Boeing's analysis of 10 years' data suggests that this probability is "almost zero". The extension would allow use of optimum routes, however, by giving pilots "-the flexibility to divert to a previously unavailable northerly airport if it met landing requirements en route". Boeing says this would save 20-30min, compared with the longer southerly alternates, where airports such as Midway would be the only available diversion sites.
Boeing stresses that the optimum route, when good weather prevails, can be operated under 120min rules. The extension, however, would allow operators "-to fly the optimal route almost all of the time, no matter what the circumstances". Boeing quotes as a precedent the 15% extension (18min) to the 120min ETOPS limit granted to some North Atlantic operators in the mid-1980s because bad weather forecasts forced so many flight cancellations.
Boeing says it is talking to the airlines, the FAA and pilot unions, some of which have expressed reservations.
Source: Flight International
