Which of the following defines "density altitude"?

Density altitude is defined as pressure altitude corrected for non-standard temperature. This is important because as temperature increases, the density of the air decreases. Higher temperatures decrease air density, which can adversely affect aircraft performance.

When pilots refer to density altitude, they’re effectively accounting for how temperature affects the performance of the aircraft. For example, if an aircraft is trying to take off in a high-density altitude situation, the thinner air can result in reduced engine performance, lower lift from the wings, and overall diminished climb capability.

Understanding density altitude is essential for pilots because it directly impacts takeoff distances, climb rates, and overall flight performance. By using pressure altitude and adjusting for the actual temperature compared to the standard temperature, pilots can determine the true altitude at which their aircraft will perform.

Other choices, while related to altitude concepts, do not accurately define density altitude. The first choice describes a scenario relevant to standard atmospheric conditions rather than the adjustments necessary for varying temperatures. The third choice mentions altitude in mountainous areas, which is unrelated to air density. The fourth option ties to weight but does not concern air density or performance characteristics relevant to flight conditions.