Carburetor Heat – March 20, 2017

We strongly recommend that you consider adding to your preflight inspection
checklist a carburetor heat functionality test. Due to the location of the carburetor on
the Safari, we are concerned that operators may believe that carburetor icing is not
possible. It is unlikely, but it is certainly possible.

In addition to checking the function of the carburetor heat cable, the pilot should
observe the carburetor temperature gauge for function. Before starting the engine,
the carburetor temperature gauge and the outside temperature gauge should show
similar readings. When the engine is started, the carburetor temperature will decrease
temporarily until the engine warms. When the fuel is increased to flight level, the
carburetor temperature will drop further. If the carburetor temperature falls below
40° F, we recommend that the pilot apply carburetor heat.

We also suggest that you review your Pilot’s Operating Handbook information
regarding carburetor temperature ranges.