According to the presently discloses subject matter, a flight path is autonomously generated (e.g. in response to an unexpected need to land the aircraft) leading the aircraft from its current position towards a target destination (e.g. a landing site) where the flight path is generated while taking into consideration flight constraints existing in the area and avoiding violation of the flight constraints. The flight path is then used for autonomous generation of flight instructions for controlling the aircraft and leading the aircraft to the desired destination.