Commercial Pilot License (CPL) Practice Exam 2026 - Free Commercial Pilot License Practice Questions and Study Guide

The correct answer is the Janitrol gas combustion heater, which is commonly used in aircraft, including the Piper Seminole, to provide heat to the cabin. This type of heater operates by burning fuel and utilizing the heat generated for cabin warming. It is particularly effective, as it can provide a consistent and controlled heat source that is necessary for comfort during flight in colder temperatures.

Electric resistance heaters are generally used in some smaller aircraft and might not be as efficient for larger cabins like that of the Seminole. Heat exchangers from the engines could be overcomplicated for direct cabin heating, as they would typically involve a different method requiring more complex airflow management. Lastly, radiators positioned in the wings are not a standard feature for cabin heating and are primarily used for cooling the engine, so they would not provide heat as required. The Janitrol heater is specifically designed and integrated into the aircraft's system to fulfill the need for cabin warmth effectively.