Alaska Airlines has developed technology that allows its pilots to see through fog, dramatically reducing the number of delayed departures and overflights to other cities during periods of poor visibility.
The technology is known as RNP, or required navigational performance system, and is the focus of Project Juneau, which was implemented on flights to Alaska's capital city in 1999 after testing that began in 1996.
RNP doesn't rely on airport controllers or ground radar. It is an adjunct to global positioning. It reads the terrain from the cockpit, and then tells the pilot exactly where he is and where he should fly in relation to latitude, longitude and altitude, the speed at which the plane should travel and the angle of descent.
Simultaneously, the pilot can see the landscape around and beneath the plane in various coded colors on a screen in the cockpit.
RNP allows jets to land when clouds are down to 337 feet three-quarters of a mile from the airport. The success of RNP means Alaska Air can land or take off from Juneau about a dozen times a month under fog, cloud or storm conditions that would have been delayed or rerouted in the past.
Training for pilots to use RNP is "very substantial," said Alaska Air spokesman Jack Walsh on Tuesday. It includes two hours of classroom ground school, two hours of hands-on practice, two hours in a fixed-flight simulator, four hours in the full-motion simulator and air time with a more experienced pilot.
Although Alaska Air could market the technology for profit, the company says it has no such intentions.
"We are very proud of it and want to share it," said Joseph Sprague, director of regional sales-Alaska, during a recent trip to Juneau. The company has applied to install RNP at the airport in San Francisco, which has many days of poor visibility.
"Whenever flights to San Francisco are canceled," said Bill McKay, Alaska Airlines' vice president of public and government affairs, "it dominoes through our whole system and wreaks havoc on our schedule."
Currently RNP is in use only in Alaska cities, including Juneau, Sitka, Kodiak, Cordova, Wrangell, Petersburg and Ketchikan, said Clifford Argue, staff vice president of properties and facilities.
RNP has been integrated in most of Alaska Airlines' planes, chiefly 737-400s and 700s. The 737-900s are now coming off the assembly line equipped with the system, said Walsh.
"It's not a unit, it's a combination of several systems that work together," Walsh said, "so it's hard to come up with a cost because some planes have to be retrofitted."
Nine 737-200s still lack the RNP, "and we're working on that," Walsh added.
MD-80s have not been equipped with RNP because they do not fly in Southeast Alaska.