Commercial Pilot Airplane (CAX) Performance Practice Exam 2025 - Free CAX Performance Practice Questions and Study Guide

To determine the ground roll needed over a 50-foot obstacle at a pressure altitude of 5,000 ft with a weight of 3,300 lb and a headwind of 15 knots, several factors come into play, notably the effects of altitude, aircraft weight, and wind conditions on takeoff distance.

The pressure altitude of 5,000 ft influences the aircraft's engine performance and the aerodynamic characteristics. As altitude increases, the air density decreases, which generally leads to a longer takeoff distance because the aircraft generates less lift and the engines produce less thrust compared to sea level conditions.

In this scenario, the presence of a 15-knot headwind is advantageous. It effectively reduces the ground speed required for takeoff, thus reducing the distance needed to reach the necessary speed for lift-off. Wind components significantly impact the takeoff performance; a headwind decreases the takeoff distance because it allows the aircraft to reach the required lift-off speed more rapidly compared to a calm condition or a tailwind.

Considering these elements, the combination of the weight of the aircraft, the altitude, and the headwind leads to the calculated distance of 1,950 feet over a 50-foot obstacle being the most appropriate choice. This choice strikes a balance