The invention relates to an autonomous helicopter for recreational purposes or for a swarm-type surveillance system, characterised in that the helicopter has a complete automatic flight control, and in that the flight thereof is stable and automatic due to a device for the automatic control of the altitude, comprising at least two optical receivers, at least one optical emitter, at least two channels for processing signals of the receivers, and at least two motors controlling at least two propellers, at a speed proportional to the total amount of signals received. Said helicopter avoids obstacles by means of an orientation device controlled by the difference between the signals of the two receivers. It advances at a regular speed by means of a shift of the centre of gravity thereof in front of the axis of the two lifting propellers.