AFOQT Practice Test

What does parasite drag refer to in an aircraft?

1. Drag caused by the shape of the aircraft

2. Resistance due to various factors like skin friction and tire pressure

3. Drag that increases with lift and airspeed

4. Drag experienced only during descent

The correct answer is: Resistance due to various factors like skin friction and tire pressure

Parasite drag is the resistance an aircraft encounters as it moves through the air, and it consists of different components that contribute to this overall drag. The correct understanding highlights that parasite drag is influenced by factors such as skin friction, which arises from the surface texture of the aircraft, and pressure drag, which results from the shape of the aircraft disrupting airflow. Additionally, tire pressure can play a role in the overall drag experienced during flight. The essence of parasite drag is that it does not vary with lift—the primary factor that differentiates it from induced drag, which does indeed increase with lift. Thus, while all the factors mentioned in the response are accurate and relevant to the concept of parasite drag, the emphasis on resistance due to skin friction and other variables directly addresses how this drag manifests irrespective of lift or descent phases of flight.