What are the four forces that affect an aircraft during flight?

The four forces that affect an aircraft during flight are lift, gravity, thrust, and drag.

Lift is the upward force generated by the wings as air flows over them, allowing the aircraft to rise off the ground. Gravity is the downward force that pulls the aircraft toward the Earth, countering lift. Thrust is the forward force produced by the engines, propelling the aircraft through the air. Drag is the resistance force that opposes the aircraft's forward motion, caused by friction and changes in the flow of air around the aircraft.

Understanding these four forces is crucial for flight attendants, as they're integral to how an aircraft operates and affects the safety and comfort of passengers during flight. Recognizing how these forces interact helps flight attendants to better understand the mechanics of flight, which can be useful when providing safety demonstrations or responding to passengers’ needs during turbulence or other flight conditions.