Alaska Airlines and its sister carrier Horizon Airlines began testing required navigation performance (RNP) at Seattle-Tacoma International Airport in June in a bid to reduce emissions and flight-path length. The project, dubbed "Greener Skies" and includes cooperation with the Port of Seattle, Boeing and FAA, involved testing of an Alaska Airlines Boeing 737-700 during a noncommercial flight. The plane flew a consistent and controlled approach to the airport. The airline said it is seeking FAA approval for the procedures, which could ultimately be used by all properly equipped carriers at the airport. Alaska Airlines estimates the procedures will cut fuel consumption by 2.1 million gallons annually and reduce carbon emissions by 22,000 metric tons, the equivalent of taking 4,100 cars off the road every year. In addition, they will reduce overflight noise exposure for an estimated 750,000 people living within the affected flight corridor. "These improved flight procedures at Sea-Tac will help Alaska Airlines and Horizon Air minimize the environmental impact of our flying on the communities we serve," said Gary Beck, Alaska’s vice president of flight operations. "With FAA approval, we hope the procedures will be available to all carriers and gradually integrated into the Seattle air traffic system. This project could also become a blueprint for expanded use of next-generation technology at more U.S. airports." Alaska Airlines, which pioneered RNP technology in the mid-1990s, uses FAA-approved RNP procedures at 23 U.S. airports. Alaska Airlines said its fleet is completely equipped with RNP, and Horizon Air’s fleet soon will be fully RNP-equipped as well. For more on RNP