What performance factor decreases at high density altitude?

What performance factor decreases at high density altitude?

• A. Takeoff distance
• B. Climb rate
• C. Engine power
• D. Payload capacity

Answer: (B)

Density altitude is a measure of how the air behaves as if you were at a higher altitude, taking into account temperature and pressure. When the air is thinner, the wings generate less lift for a given airspeed and the engine/propeller produce less thrust. After takeoff, this combination reduces the excess power available to climb, so the airplane can gain altitude more slowly. That slower vertical progress is what we mean by a decrease in climb rate. While engine power and takeoff distance are also affected by thinner air, the rate of climb is the key performance factor that falls off with increasing density altitude. Payload capacity isn’t inherently reduced by density altitude—though higher density altitude can force you to carry less payload to meet climb performance requirements.

Density altitude is a measure of how the air behaves as if you were at a higher altitude, taking into account temperature and pressure. When the air is thinner, the wings generate less lift for a given airspeed and the engine/propeller produce less thrust. After takeoff, this combination reduces the excess power available to climb, so the airplane can gain altitude more slowly. That slower vertical progress is what we mean by a decrease in climb rate. While engine power and takeoff distance are also affected by thinner air, the rate of climb is the key performance factor that falls off with increasing density altitude. Payload capacity isn’t inherently reduced by density altitude—though higher density altitude can force you to carry less payload to meet climb performance requirements.