  Experimental flight tests are reported about quadrotors UAVs via a recent
model-free control (MFC) strategy, which is easily implementable. We show that
it is possible to achieve acrobatic rate control of the UAV, which is beyond
the previous standard. The same remote controller is tested on two physical
vehicles without any re-tuning. It produces in both cases low tracking error.
We show that MFC is robust even when the quadrotor is highly damaged. A video
footage can be found at: https://youtu.be/wtSLalA4szc
