The fans in front help to produce an air cushion, because the wing is tilted like a wedge and so the air is trapped below the wing surface and like a hovercraft it can elevate up at the beginning, so it can really lift off at nearly zero speed. And later you can tilt these thrusters in the front to get into a more streamlined, so which is then in the performance, better. So you use tillable rotors in the front to lift off at lower speed and fly at higher speed.