(1) Prevention of ice formation is far more effective and satisfactory than attempts to dislodge the ice after
it has formed. If icing conditions are inadvertently encountered, turn on the anti-icing systems at the irst sign of ice
(2) Do not operate deicer boots continuously. Allow at least 0.5 inch of ice on the wing deicer boots
or 0.25 inch on the antenna deicer boots before activating to remove the ice. Continued light in severe icing
conditions should not be attempted. If ice forms on the wing area aft of the deicer boots, climb or descend to an
altitude where conditions are less severe.
g. Landing. Extreme care must be exercised when landing on ice or slippery runways. Excessive use of either
brakes or power may result in an uncontrollable skid. Ice accumulation on the aircraft will result in higher stalling
airspeeds due to the change in aerodynamic characteristics and increased weight of the aircraft due to ice buildup.
Approach and landing airspeeds must be increased accordingly.
8-55. SEVERE ICING.
a. The following weather conditions may be conducive to severe in-light icing:
Visible rain at temperatures below zero degrees Celsius ambient air temperature.
(2) Droplets that splash or splatter on impact at temperatures below zero degrees Celsius ambient air
b. The following procedures for exiting a severe icing environment are applicable to all light phases from takeoff
(1) Monitor the ambient air temperature. While severe icing may form at temperatures as cold as 18
degrees Celsius, increased vigilance is warranted at temperatures around freezing with visible moisture present.
(2) Upon observing the visual cues speciied in the limitations section of this manual for the identiication
of severe icing conditions (reference paragraph 5-35), accomplish the following:
(a) Immediately request priority handling from air trafic control to facilitate a route or an altitude change
to exit the severe icing conditions in order to avoid extended exposure to light conditions more severe than those
for which the aircraft has been certiicated.
Avoid abrupt and excessive maneuvering that may exacerbate control dificulties.
Do not engage the autopilot.
If the autopilot is engaged, hold the control wheel irmly and disengage the autopilot.
If an unusual roll response or un-commanded roll control movement is observed reduce the angle-
(f) Do not extend laps during extended operation in icing conditions. Operations with laps extended
can result in a reduced angle-of-attack, with the possibility of ice forming on the upper surface further aft on the wing
than normal, possibly aft of the protected area.
If the laps are extended, do not retract them until the airframe is clear of ice.
Report these weather conditions to air trafic control.