In this paper, an adaptive controller is proposed for attitude and altitude control of a quadrotor. First, mathematical and dynamic models of a quadrotor are analyzed. Next, PID and LQR controllers are designed separately. This step is followed by application of hyperbolic tangent weight function to increase the overall performance by selecting the proper controller at proper time. Finally, all the three controllers' performances are observed in Matlab Simulink simulation environment. Simulations show that adaptive controller's overall performance is remarkably superior to that of a single PID or LQR controller.