Which altitude should be used to reflect performance effects caused by nonstandard temperature?

• A. Density altitude
• B. True altitude
• C. Absolute altitude
• D. Pressure altitude

Answer: (A)

Density altitude is the altitude in the standard atmosphere that has the same air density as the air you’re actually flying in. Temperature directly affects air density: hotter-than-standard air becomes thinner, reducing lift for a given speed and making performance worse (climb rate, stall speed, and glide characteristics) just like flying at higher altitude. Cool temperatures increase density and improve performance. So, to reflect how nonstandard temperature changes affect performance, you translate the current conditions to a density altitude. The other altitudes describe actual height, pressure effects, or true height above the surface, but they don’t capture the density changes that drive performance.