Microwave Radiometers Help Keep Aircraft Safe From Icing

One of the greatest dangers to aircraft — playing a role in numerous destructive and fatal accidents around the world — comes in the form of droplets of water. In clean air, cloud droplets can exist in liquid form down to temperatures as low as -40 °C. These subfreezing, liquid clouds are referred to as being “supercooled.” As soon as supercooled droplets contact an aircraft ascending or descending through the cloud cover, they form layers of ice on any unprotected surface, including the leading edges of wings and rotor blades, tails, antennas, and within jet engines. This ice accretion can cause engine damage and dramatically affect the aerodynamics of the aircraft. On the leading edge of a wing, an ice layer about as thick and rough as a piece of coarse sandpaper can be responsible for as much as a 30% decrease in lift and a 40% increase in drag. This can lead to reduced performance and even catastrophic loss of control.