Certified Flight Instructor - Flight Instructor Airplane Practice Exam

What is the primary function of the pitot tube in an aircraft?

1. To measure altitude.

2. To provide information on airspeed.

3. To detect changes in ambient temperature.

4. To indicate fuel pressure.

The correct answer is: To provide information on airspeed.

The primary function of the pitot tube in an aircraft is to provide information on airspeed. The pitot tube is an essential component of the aircraft's airspeed indicator system. It measures the dynamic pressure of the air flowing into it as the aircraft moves through the atmosphere. This pressure is then correlated with static pressure from a static port to calculate the airspeed, which is displayed to the pilot. Understanding airspeed is critical for flight safety and performance, as it affects lift, drag, and stall speed, among other factors. By accurately measuring the difference between the total pressure (which includes the effects of the aircraft's forward motion) and the static pressure of the surrounding air, the pitot tube plays a vital role in ensuring that pilots have accurate information to maintain control of the aircraft. The other options relate to different systems in the aircraft: altitude is measured by altimeters that use static pressure, temperature changes are typically detected by temperature gauges, and fuel pressure is monitored through a separate gauge system. Each of these components has distinct roles in aviation, but they do not pertain to the function of the pitot tube.