[Avionics Today June 27, 2014] Alaska Airlines is starting to realize the fuel saving benefits of the FAA's Next Generation Air Transportation System (NextGen) in Seattle, according to testimony from the carrier's vice president of flight operations Gary Beck before the Senate subcommittee on aviation. The airline is using new flight procedures as a result of the agency's Greener Skies initiative, a regional rollout of NextGen implementation that is currently in its second phase.
Infographic shows the goals of the Greener Skies program in Alaska. Photo, courtesy of the FAA.
During the first phase of the program, which began in 2010, the primary objective was to develop and implement two Area Navigation (RNAV) arrivals and six Required Navigation Performance (RNP) approaches, Beck said. Arrivals are published flight procedures that take the aircraft from its cruising altitude down to a few thousand feet as it transitions into the airport, while approaches take the aircraft from that position to the runway.
RNAV is a flight procedure that allows an aircraft to fly on any desired path rather than being contained to an airway. RNP refers to the ability of onboard avionics to enable flight of the aircraft along a precise flight path. This is a much more efficient arrival than the traditional process, where the pilot slowly descends the aircraft into its arrival in a stair step manner, descending and then leveling off before ascending again and repeating the process until landing. Beck says the "NextGen arrivals are akin to the plane sliding down the banister rather than taking the stairs."
"The biggest bang for our buck as an operator is from cruise altitude to the end of the runway. Ideally if we can make an arrival and an approach and not touch those power levers once we bring them back to idle until we're on short final, that's where we're going to get the most bang for our buck from fuel savings, emissions and noise too," said Beck.
So far, implementing the two new RNAV arrival procedures has provided a 17 mile savings over previous landing procedures for aircraft landing to the southern runway at SeaTac. Beck estimates that leads to a fuel savings of 44 gallons of fuel per flight, which leads to an annual savings of 1.3 million gallons of fuel for the 30,000 aircraft that fly the arrival annually.
That estimate assumes that all of the aircraft flying that arrival have onboard avionics that enable the pilots to perform RNP approaches.
While the Seattle Greener Skies initiative is already saving Alaska Airlines fuel with NextGen arrivals, the overall use of Performance Based Navigation (PBN) procedures throughout the National Airspace System (NAS) is relatively low, according to Matthew Hampton, assistant inspector general for aviation audits, who also testified during the Senate aviation subcommittee hearing.
PBN is one of the priorities of the NextGen rollout that was identified by the NextGen Advisory Committee (NAC) in late 2013.
"Although FAA has introduced more than 100 RNP procedures at large airports, preliminary data14 indicate that RNP use is low, particularly at busy airports," said Hampton.
"Notably, at the 14 large airports where FAA has implemented advanced PBN procedures with curved approaches to runways, only about 2 percent of eligible airline flights actually used them."
The FAA will submit a 2014 midterm report on overall NextGen progress to lawmakers on July 1.