What are four factors that affect density altitude?

The correct choice highlights four critical factors that influence density altitude: temperature, pressure, altitude, and humidity.

Temperature affects density altitude because as the temperature increases, the density of the air decreases, leading to a higher density altitude. Warm air is less dense than cold air, which means that at higher temperatures, the aircraft experiences reduced performance due to less lift and decreased engine efficiency.

Pressure is another key factor; lower atmospheric pressure also results in lower air density. As the pressure decreases, the density altitude increases. This is often experienced in high-altitude regions or during weather changes, such as when a low-pressure system moves into an area.

Altitude, or the elevation of the location above sea level, plays a direct role in density altitude. As you ascend in altitude, the air becomes thinner, which raises the density altitude relative to sea level.

Lastly, humidity significantly impacts air density as well. Higher levels of moisture in the air reduce its density compared to dry air, further increasing the density altitude.

Together, these four factors directly interact with the performance metrics of an aircraft, particularly during takeoff and landing, making understanding them crucial for pilots.