The average price of jet fuel in the U.S. is edging upward, according to two independent surveys. Within the lower 48 states, Fillup Flyer Fuel Finder (www.fillupflyer.com) reported that the average price in late March was $2.63 a gallon, up about 15 cents since January. The highest price found by Fuel Finder was $4.15 a gallon in the Southeast region. Meanwhile, AirNav figures (www.airnav.com) show the national average (including Alaska) to be $2.53 a gallon in late March. The highest price found was $4.50 in Alaska, typically the state with the most expensive fuel.