Earlier this month, the Seattle Times reported that the Federal Aviation Administration’s (FAA) project, “Greener Skies Over Seattle“, calls for “significant changes” in flight patterns to airplanes approaching Sea-Tac airport from the northwest and southwest. So, rather than jets flying over North Seattle, they’d be re-routed over Elliott Bay, with a final approach over Harbor Island.
The changes in flight patterns are part of “NextGen,” a larger project by the FAA to reduce the use of fuel and to lower emissions by using “Optimized Profile Descents” (OPDs), which is a fancy way of saying that the pilots could set the jet’s engines “near idle throttle while they descend, instead of flying the more typical ‘step-down’ approaches with intervening level flight segments, increased throttle settings, and added fuel burn.” A tighter descent path is also possible, using a new aircraft navigation called Performance Based Navigation (PBN), which, according to this riveting video, is “a new method that uses on board avionics to navigate with greater precision and accuracy,” using advanced flight management systems that are on board aircraft, on the ground, and in space. Two key elements include Area Navigation (RNAV) and Required Navigation Performance (RNP). With the new technology, “pilots no longer need to zig zag from one ground navigation to another, which helps to reduce flight distances, and allows aircraft to fly more accurate paths within a narrow corridor.” The improvement means more lanes can be built in airspace, and RNAV and RNP can also allow pilots to use safe and flexible re-routes for changing weather conditions.
The project is still in flight trials and is undergoing an environmental assessment, and must be reviewed for compliance with a score of airline, safety, and environmental agencies including the National Environmental Policy Act of 1969; but once the project receives the A.-O.K., the new procedure would be implemented by Alaska Airlines and Southwest Airlines. In the meantime, two meetings are scheduled to allow for public comment. The first one will be held on September 5, from 6:00pm to 7:30pm at the Federal Way Library, and the second will be held on September 6 at the Ballard Public Library, also from 6:00pm to 7:30pm.
Thanks to Rachel F. for sending us this story!