Which of the following is one of the four main forces acting on a helicopter and acts downward toward the Earth's center?

Which of the following is one of the four main forces acting on a helicopter and acts downward toward the Earth's center?

• A. Gravity
• B. Lift
• C. Thrust
• D. Drag

Answer: (A)

Gravity, the downward pull of the Earth on the helicopter, is the force that acts toward the Earth's center. This is the weight of the helicopter, the force that must be balanced to hold a hover or climb. Lift, generated by the rotor, acts upward to counteract this downward pull. Thrust pushes the helicopter through the air, and drag resists that motion, acting opposite the direction of travel. The key idea is that gravity always points straight down, toward the Earth, making it the downward force among the four main forces.

Gravity, the downward pull of the Earth on the helicopter, is the force that acts toward the Earth's center. This is the weight of the helicopter, the force that must be balanced to hold a hover or climb. Lift, generated by the rotor, acts upward to counteract this downward pull. Thrust pushes the helicopter through the air, and drag resists that motion, acting opposite the direction of travel. The key idea is that gravity always points straight down, toward the Earth, making it the downward force among the four main forces.