The Northwest Iowa Regional Airport will end commercial air service out of Spencer this spring. Great Lakes Aviation vice president Dick Fontane says flights will end on April 30th.Fontane says the price of fuel and government regulation are factors in the decision but the main reason is competition. He says the arrival of Southwest Airlines in Omaha led to lower fares and passengers were going there to fly.Fontane says daily flights will be cut from four to two next week. Great Lakes was started in Spencer in 1981. Their offices are now located in Cheyenne, Wyoming.