Exterior helicopter light unit and method of operating an exterior helicopter light unit

An exterior helicopter light unit (2) is disclosed that comprises a movable light head (4) comprising a light source, a first motor (10) and a second motor (20) for actuating the movable light head (4), and an inverse differential gear assembly (30) coupling the first and second motors (10, 20) to the movable light head (4) in such a way that the first and second motors (10, 20) can tilt and rotate the movable light head (4) in operation.