PLT190: Carburetor Ice
What code PLT190 covers, why the FAA tests it, and how to study Carburetor Ice before your checkride.
Recall carburetor ice - factors affecting / causing
What this means for your checkride
Carburetor ice forms when fuel vaporization and the pressure drop through the venturi cool the carburetor below freezing, and moisture in the air freezes there and chokes the airflow. It is most likely at low power with high humidity and can form at outside temperatures well above freezing.
Carburetor ice is a leading cause of power loss in carbureted engines, so the FAA tests the conditions that cause it and the correct use of carburetor heat.
Many believe carb ice only happens near or below freezing outside. The venturi cooling means it can form on a warm, humid day at reduced power.
Where to study it
A code on your test report is an area of deficiency. An authorized instructor must review it with you and endorse that review before you take the practical test, and the examiner may revisit it during the oral. Study it until you can explain it out loud, not just recognize the answer.