It is a glider. The total aerodynamic force vector still points straight up, directly opposite to gravity. This is always the case for unaccelerated flight. A light plane might have a (drag, lift) lbs-f vector of (-200, 2000) where the flight path is the x axis. In a glide you rotate this coordinate system so the total aerodynamic vector points straight up, placing the x-axis aka flight path at the correct inclination. Greater drag values result in steeper flight paths. If you had an engine the thrust would offset drag and the vector would be (0, 2000) resulting in level flight. With excess thrust the vector might be (200, 2000) and the aircraft would climb. In a terminal velocity vertical dive it would be (-2000, 0) aka a parachute.
It is a glider. The total aerodynamic force vector still points straight up, directly opposite to gravity. This is always the case for unaccelerated flight. A light plane might have a (drag, lift) lbs-f vector of (-200, 2000) where the flight path is the x axis. In a glide you rotate this coordinate system so the total aerodynamic vector points straight up, placing the x-axis aka flight path at the correct inclination. Greater drag values result in steeper flight paths. If you had an engine the thrust would offset drag and the vector would be (0, 2000) resulting in level flight. With excess thrust the vector might be (200, 2000) and the aircraft would climb. In a terminal velocity vertical dive it would be (-2000, 0) aka a parachute.
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