It will stall and begin to lose altitude.
Lift, weight, thrust and drag.
Drag
Aerodynamics help reduce drag so the engines can produce thrust.
Lift equals weight and thrust equals drag.
Lift, Gravity, thrust and drag
Friction is the force resisting the movement of an object across a surface. For an airplane there is no friction when it is flying. Instead this is referred to as air resistance which produces drag forces. There are several forces acting on the airplane at one time: Thrust, Drag, Lift, and Gravity.
lift and thrust overcome weight and drag
Lift, thrust, drag, and gravity affects all flying objects and wildlife. The blades of the helicopter provide lift, drag and thrust.
If drag and thrust are equal, a flying device will stop ACCELERATING, that is it will maintain a constant speed.From classical Newtonian physics:Force = mass x accelerationSince drag and thrust are forces, we have:Thrust - drag = mass x accelerationSince you say that drag and thrust are equal, and the mass of a flying object is some finite value, it turns out that the acceleration = 0, i.e. a constant speed
There are four forces that act on an airplane that keeps it at a level altitude. Thrust, drag, weight, and lift determine whether a pilot flies at a level altitude.
Thrust (forward), Gravity (down), Drag (back), Lift (up)
LIFT -- force provided by the wing and in perpendicular direction to the wing. In straight and level flight the lift is exactly equal to the aircraft weight. WEIGHT -- the force pulling vertically down on the airplane due to gravity. In straight and level flight this is equal to the lift. THRUST -- the force that pulls the airplane forward, provided by the propeller or jet engine. If the airplane is flying at a constant speed in level flight, this thrust is exactly equal to the drag. DRAG -- the aerodynamic force on the airplane in the opposite direction of its travel. Drag is due to skin friction, form drag (drag around wheels, struts, etc) and induced drag (produced by the wing as a side effect of lift)