The FAA has proposed levying a $304,000 civil penalty against Cheyenne, Wyo.-based Great Lakes Aviation for allegedly conducting 19 flights following improper application of de-icing fluid. The FAA maintains that Great Lakes flew Beech 1900Ds out of Hays, Kan., in January 2011 with de-icing fluid that exceeded the maximum temperature of 180 degrees F. The Great Lakes de-icing manual states that fluid heated to more than 180 degrees could damage the aircraft or the de-icer.

Great Lakes had 30 days from receipt of the FAA’s December 2 enforcement letter to respond to the agency.