Would the kinetic energy of a plane increase or decrease as the plane climbs higher in the air?

Would the kinetic energy of a plane increase or decrease as the plane climbs higher in the air?


Also if the plane holds a constant speed but still ascends, what happens to it's total mechanical energy?|||Would the kinetic energy of a plane increase or decrease as the plane climbs higher in the air?





Not necessarily either.





Airplanes do not just coast around. Only glider aircraft do that...and for a glider aircraft with no cable attaching it to a tow plane, it would indeed would be the case that it would loose kinetic energy as it ascends.





Airplanes have the engines that they can use to change the sum total of GPE and KE as per their need.











"Also if the plane holds a constant speed but still ascends, what happens to it's total mechanical energy?"





It increases. The new mechanical energy originates from the fuel that was burned, the portion of the energy that energy that became thrust.|||The plane could be climbing at constant speed, and the kinetic energy would stay constant.


It could be slowing down as it climbed, and the kinetic energy would decrease.


It could be climbing at an increasing speed, and the kinetic energy would increase.





If it's climbing at constant speed, its gravitational potential energy will increase, and its total mechanical energy will increase as well.|||KE depends on the mass and velocity ONLY, not the height.





At constant speed and ascending, its total ME increases: ME = KE + m*g*h