Because international aviation regulators and aerodynamic experts failed again last week to reach agreement about the extent of the safety hazards created by Airbus A380 wake turbulence, interim guidelines remain in effect. When the interim recommendations were adopted late last year the experts had expected to reach a consensus earlier this year on final guidelines. Under the interim guidelines, the International Civil Aviation Organization (ICAO) is calling for minimum spacing of 10 nm between a landing A380 and a following aircraft, twice the current FAA requirement. For aircraft flying behind an A380 on the same route and at the same altitude, ICAO is recommending that the minimum distance be tripled to 15 nm. The interim guideline also recommends extending wait time by one minute–beyond today’s typical two minutes–for smaller aircraft waiting to take off behind an A380. Meanwhile, introduction into service of the world’s largest passenger jet has been delayed again–to early next year.