Private Pilot Stage 3 Practice Test

Higher temperatures reduce engine power and lift, which negatively impacts climb performance. This phenomenon is primarily due to a decrease in air density as temperature increases.

When the air is warmer, it becomes less dense, meaning that there are fewer air molecules in a given volume. Engines rely on the intake of air to mix with fuel for combustion; therefore, as air density decreases, the engine produces less power. This diminished power output directly affects the aircraft's ability to climb because the thrust provided by the engines is lower.

Additionally, lift, which is generated by the wings, is also influenced by air density. Lift is a function of the air pressure above and below the wings. With less dense (warmer) air, the wings are unable to generate as much lift at the same speed compared to cooler air. Therefore, the aircraft requires a higher true airspeed or a higher angle of attack to achieve the same amount of lift in warmer conditions.

In summary, higher temperatures adversely affect both engine performance and lift, leading to reduced climb performance, making this option the correct choice.