SIFT Army Aviation Information Practice Test

What is the primary factor affecting a helicopter's potential energy?

1. The tail rotor's anti-torque force

2. The relative wind

3. The aircraft's altitude

4. The weight of the aircraft

The correct answer is: The aircraft's altitude

The primary factor affecting a helicopter's potential energy is the aircraft's altitude. Potential energy in the context of aviation is calculated using the equation PE = mgh, where "m" stands for mass (or weight), "g" is the acceleration due to gravity, and "h" is the height above a reference point, typically the ground or sea level. As altitude increases, the height ("h") increases, thereby increasing the potential energy of the helicopter. This energy is crucial because potential energy can be converted into kinetic energy when the helicopter descends, allowing the aircraft to perform maneuvers or maintain control during flight. While weight does play a role in potential energy (since it is part of the formula), altitude is the variable that directly affects the quantity of potential energy in a more significant way, as increasing altitude raises the overall potential energy of the helicopter.