Ruling Means Newest 747 Can Operate Under Same Separation Distance As 747-400

The International Civil Aviation Organization (ICAO) has ruled that Boeing's new 747-8 will be able to operate at the same separation distances as the 747-400, designated as "heavy." ICAO, a United Nations agency tasked with codifying principles and techniques for international air navigation, sent a letter to all member nations recently saying that a team of wake experts had examined flight test and simulation data, and that it determined that the 747-8 should remain in the same class as its predecessor and retain the same separation distances.

A special ICAO team of experts in the field of wake vortices from the U.S. Federal Aviation Administration (FAA), the European Organization for the Safety of Air Navigation (EUROCONTROL), the European Aviation Safety Agency (EASA) and the manufacturer "examined flight test and simulation data and established safety case arguments for approach, landing, departure, climb/descent and cruise operations of the Boeing 747-8 relative to other aircraft," the ICAO letter said. "The safety case supports the assertion that the Boeing 747-8 is safely categorized as HEAVY. Consequently, the wake turbulence separation minima specified ... for HEAVY aircraft should be applied."

Receiving "heavy" designation and the same separation criteria as the 747-400 is an important accomplishment for the 747-8 program, said Todd Zarfos, vice president, engineering, 747 program. "We promised our customers that the 747-8 would be able to operate in the same markets and routes they use for the 747-400," he said. "We did extensive testing to show that even though the 747-8 is longer, heavier and has a bigger wingspan than the 747-400, it does not create greater wake vortex effects. That means that airports will be able to operate more efficiently and not have to slow down operations to accommodate this airplane. Combined with its lower noise footprint, the 747-8 will be a great addition to the world's airport operations."

FMI: www.icao.int