Turning radius

Minimum dimension for a vehicle to make a turn Diagram showing the path of a driver performing a U-turn. A vehicle with a smaller turning diameter will be able to perform a sharper U-turn. The turning radius (alternatively, turning diameter or turning circle) of a vehicle defines the minimum dimension (typically the radius or diameter) of available space required for that vehicle to make a semi-circular U-turn without skidding. The Oxford English Dictionary describes turning circle as "the smallest circle within which a ship, motor vehicle, etc., can be turned round completely". The term thus refers to a theoretical minimal circle in which for example an aeroplane, a ground vehicle or a watercraft can be turned around. The terms (radius, diameter, or circle) can have different meanings; refer to the § Alternative nomenclature section. Definition Diagram of turning vehicle. On wheeled vehicles with the common type of front wheel steering (i.e. one, two or even four wheels at the front capable of steering), the vehicle's turning diameter measures the minimum space needed to turn the vehicle around while the steering is set to its maximum displacement from the central 'straight ahead