AFOQT Practice Test

What does a pressure altimeter measure?

1. Flight speed based on engine power

2. Altitude based on atmospheric pressure

3. Air density for optimal performance

4. Flight path stability

The correct answer is: Altitude based on atmospheric pressure

A pressure altimeter is an instrument used in aviation that measures altitude based on atmospheric pressure. It operates on the principle that atmospheric pressure decreases with increasing altitude. As an aircraft climbs, the surrounding atmospheric pressure decreases, and the altimeter senses this change and translates it into altitude. This is significant for pilots because it allows them to maintain proper altitude levels during flight, which is crucial for safety, navigation, and compliance with air traffic control instructions. The accurate measurement of altitude is essential for avoiding terrain and ensuring correct altitude settings in different phases of flight. While options related to flight speed, air density, and flight path stability are important in aviation, they do not pertain to the specific function of a pressure altimeter. Only the measurement of altitude based on changes in atmospheric pressure accurately describes the role of this instrument.