Drone Pilot Practice Exam

As altitude increases, how are pressure and density affected?

1. Pressure increases, density decreases

2. Pressure decreases, density remains constant

3. Pressure and density both decrease

4. Pressure and density both increase

The correct answer is: Pressure and density both decrease

As altitude increases, both pressure and density decrease due to the nature of the atmosphere. The atmosphere is compressible, meaning that it is denser at lower altitudes where the weight of the air is greater. As you ascend, the amount of air above you decreases, which reduces the pressure exerted by the weight of the air. Consequently, with less air above, the density of the air also decreases. This phenomenon is critical for drone pilots to understand, as changes in air pressure and density can affect drone performance, including lift, engine efficiency, and battery life. In simpler terms, the higher you fly, the thinner the air becomes, leading to both lower pressure and lower density, which is vital information for flight planning and performance assessment.