Aircraft deicing unit having rapid heating capability

A method and apparatus for deicing aircraft wherein a deicing fluid tank is provided with partitions which establish a plurality of chambers for receiving a deicing fluid, such as water, and at least one chamber for receiving an anti-icing fluid, such as glycol. The fluid to be heated is withdrawn from a selected one of the fluid chambers, heated to a predetermined temperature such as 140 DEG -190 DEG F., and returned to the same chamber preparatory to application. The temperature of the fluid in adjacent chambers is raised somewhat by conduction. The various partitions provide limited flow communication between the fluid chambers such that as fluid is withdrawn from the selected primary chamber for application onto an aircraft, the fluid in adjacent chambers replenishes the removed fluid without substantially reducing the temperature of the fluid therein, thereby requiring minimal recovery time to maintain a temperature-ready supply of fluid for a deicing operation.