The carburetor heat systems are very varied in design and effect. The techniques applied are also very varied. I agree with the point made by B2N2 that the benefit from carb ht once set to cold is short lived.
The purpose of the power checks and vital actions at the hold is to ensure that the aircraft is fit for flight. Any alterations once the checks are complete can introduce a problem, so should be done with caution. I've lost count on the occasions that an additional application of carb. ht. is made and then forgotten so lining up with heat still applied. I am insistent therefore that the hand must not be removed from the control until it is put back to cold when this additional check is done.
How many pilots know the minimum static RPM for their aeroplane with the throttle fully open. It is a much more valuable check when done against the brakes immediately prior to the T.O. roll.
Last edited by Pilot DAR; 30th Nov 2021 at 13:27.
Reason: spelling error