Curved interface between an outer end of a wing and a moveable wing tip device

An aircraft comprising a wing, the wing having a fixed wing with a wing tip device moveably mounted at the outer end thereof, the wing tip device being moveable between:

• (a) a flight configuration for use during flight;
• and
• (b) a ground configuration for use during ground-based operations, in which ground configuration the wing tip device is moved away from the flight configuration such that the span of the aircraft wing is reduced,
• wherein the wing tip device is rotatable between the flight and ground configurations, about an axis of rotation inclined with respect to a plane defined by spanwise and chordwise directions of the fixed wing, such that the wing tip device rotates upwards and rearwards when moving from the flight to ground configurations, and
• wherein, when the wing tip device is in the flight configuration, an outer end of the fixed wing and an inner end of the wing tip device meet along an interfacing cut line that separates an outer surface of the fixed wing and an outer surface the wing tip device,
• the interfacing cut line comprising a curved section, wherein a radius of the curved section is a distance between the axis of rotation and the curved section, and the radius of the curved section continuously increases along the curved section in a direction towards a leading edge of the wing tip device such that adjacent portions of the fixed wing and wing tip device on either side of the interfacing cut line, separate as the wing tip device moves from the flight configuration towards the ground configuration.