Page 737 - PPL-engelsk 2025

P. 737

Aircraft general knowledge

8.9.3.2 Practical use of carburetor heat

Carburetor ice will occur in certain situations. If you are a little high during

approach and turn off the throttle, the ice can completely cut off the fuel supply

without you noticing, because the propeller still is rotating.

When you advance the throttle, the engine will not respond because the

carburetor is blocked by ice.

This is the reason why you use preheating when you reduce engine output to

below 2000 rpm.

Avoid using carb heat for too long while taxiing on the ground, as there is a lot

of dust and other things at ground level that the engine does not benefit from.

Remember that when you activate carb heat, the engine gets a richer mixture.
This results in a further drop in rpm!

See the aircraft's POH for how to use carburetor heat! It may differ from model

to model and from type to type.

See animation about carburetor heat here: https://youtu.be/65djenNI_Ho

Back to table of contents

8.9.4 Engine cooling

Aircraft engines are cooled in several ways. Primarily by air flow around the

cooling fins of the cylinders.

8.9.4.1 Engine cooling by oil and oil cooler

Oil helps to conduct heat away from bearings and other parts. The aircraft may

also be equipped with an oil cooler that removes heat from the interior of the

engine.

732 733 734 735 736 737 738 739 740 741 742