Private Pilot Private Exam

What is the relationship between air temperature and altimeter height readings?

1. Higher temperatures lead to lower altitude indications

2. Lower temperatures lead to higher altitude indications

3. Temperature does not affect altimeter readings

4. High pressure equals high altitude

The correct answer is: Higher temperatures lead to lower altitude indications

The relationship between air temperature and altimeter height readings is crucial for pilots to understand. When air temperature increases, the air becomes less dense. This decrease in density leads to the altimeter indicating a lower altitude than the actual altitude. This is because altimeters measure atmospheric pressure, which decreases with height; warmer air is less dense and holds pressure differently than cooler air. Thus, when flying in warmer conditions, if the altimeter is not correctly adjusted for temperature deviations, it may show an altitude that is lower than the actual height above the ground, potentially leading to dangerous situations, especially when flying close to terrain. Understanding this relationship helps in ensuring safe flight operations by allowing pilots to make necessary adjustments to their altimeter settings based on local temperature conditions.