Which factors can affect aircraft performance?

Weight and balance are crucial factors that directly influence aircraft performance. The overall weight of the aircraft affects its lift, drag, and fuel efficiency. An aircraft that is too heavy may require a longer distance to take off and land, as well as increased power settings to maintain climb performance. Similarly, the aircraft's balance, which refers to the distribution of weight within the aircraft, affects its center of gravity. An improperly balanced aircraft can lead to issues such as difficulty in controlling the aircraft, increased stall risks, and overall unsafe flight characteristics.

While the other factors listed can impact performance in various ways—such as altitude affecting air density and engine performance, fuel influencing weight, and weather impacting lift and drag—weight and balance specifically play a foundational role in ensuring safe and efficient aircraft operation.