Propeller Owner's Manual
136
DESCRIPTION AND OPERATION
61-00-36
Page 2-26
Rev. 2 Feb/17
5. Propeller Ice Protection Systems
Some Hartzell Propeller Inc. compact propellers may be equipped
with an anti-ice or a de-ice system. A short description of each of
these systems follows:
A. Propeller Anti-ice System
A propeller anti-ice system is a system that prevents ice from
forming on propeller surfaces. The system dispenses a liquid
(usually isopropyl alcohol) which mixes with moisture on the
propeller blades, reducing the freezing point of the water.
This water/alcohol mixture flows off the blades before ice
forms. This system must be in use before ice forms. It is
ineffective in removing ice that has already formed.
(1) System Overview
(a) A typical anti-ice system consists of a fluid tank,
pump, and distribution tubing.
(b) The rate at which the anti-icing fluid is dispensed is
controlled by a pump speed rheostat in the cockpit.
(c) The anti-icing fluid is dispensed through airframe
mounted distribution tubing and into a rotating
slinger ring mounted on the rear of the propeller hub.
The anti-icing fluid is then directed through blade
feed tubes from the slinger ring onto the blades via
centrifugal force. The anti-icing fluid is directed onto
anti-icing boots that are attached to the leading edge
of the blade. These anti-icing boots evenly distribute
and direct the fluid along the blade leading edge.
