This paper proposes an integral approach for accurate ultra wide band indoor position control of flapping wing micro air vehicles. Three aspects are considered to reach a reliable and accurate position controller. The first aspect is a velocity/attitude flapping-wing model for drag compensation. The model is compared with real flight data and shown to be applicable for more than one type of flapping wing drone. The second improvement regards a battery-level dependent thrust control. Lastly a characterisation of ground effects in flapping-wing flight is obtained from hovering experiments. The proposed controller improves position control by a factor _ 1.5, reaching a mean absolute error of 10cm for position in x and y, and 4.9cm for position in z.