Interface between an outer end of a wing and a moveable wing tip device

An aircraft wing including a fixed wing with a wing tip device moveably mounted at an outer end of the fixed wing, 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 and the fixed wing are separated along a primary cut plane, the primary cut plane being obliquely orientated, and the wing tip device being rotatable between the flight and ground configurations, about an axis of rotation orientated normal to the primary cut plane, 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 of the wing tip device,
• the interfacing cut line comprising:
• (i) a first length, formed by a cut through the outer surface of the fixed wing, that is offset from the primary cut plane in a first direction;
• (ii) a second length, formed by a cut through the outer surface of the fixed wing, that extends within a plane containing the axis of rotation or within a plane parallel thereto;
• and
• (iii) a transition section in which the interfacing cut line transitions from the first length to the second length.

A fixed wing configured to receive a wing tip device, wherein the wing tip device is separated from the fixed wing along a primary cut plane, the primary cut plane being obliquely orientated, such that the wing tip device may be rotatable between a flight configuration and a ground configuration about an axis of rotation orientated normal to the primary cut plane, and

• wherein an outer end of the fixed wing is shaped to meet an inner end of the wing tip device along an interfacing cut line that separates an outer surface of the fixed wing and an outer surface of the wing tip device,
• the interfacing cut line comprising:
• (i) a first length, formed by a cut through the outer surface of the fixed wing and that is offset from the primary cut plane in a first direction;
• (ii) a second length, formed by a cut through the outer surface of the fixed wing and that extends within a plane containing the axis of rotation or within a plane parallel thereto;
• and
• (iii) a transition section in which the interfacing cut line transitions from a first length to a second length.

A wing tip device configured to be received on a fixed wing, wherein the wing tip device is separated along a primary cut plane from the fixed wing, the primary cut plane being obliquely orientated, such that the wing tip device may be rotatable between a flight configuration and a ground configuration about an axis of rotation orientated normal to the primary cut plane, and

• wherein an inner end of the wing tip device is shaped to meet an outer end of the fixed wing along an interfacing cut line that separates an outer surface of the fixed wing and the wing tip device, the interfacing cut line comprising:
• (i) a first length, formed by a cut through the outer surface of the wing tip device and that is offset from the primary cut plane in a first direction;
• (ii) a second length formed by a cut through the outer surface of the wing tip device and that extends within a plane containing the axis of rotation or within a plane parallel thereto;
• and
• (iii) a transition section in which the interfacing cut line transitions from a first length to a second length.

A method of designing an interface between the outer end of a fixed wing and the inner end of a wing tip device for an aircraft, 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 method comprises the steps of:
• separating the wing tip device and the fixed wing along a primary cut plane, the primary cut plane being obliquely orientated, and the wing tip device being rotatable between the flight and ground configurations, about an axis of rotation orientated normal to the primary cut plane,
• defining an interfacing cut line that separates an outer surface of the fixed wing and an outer surface of the wing tip device, by defining
• (i) a first length, formed by cut through the outer surface of the fixed wing that is offset from the primary cut plane in a first direction;
• (ii) a second length, formed by a cut through the outer surface of the fixed wing that extends within a plane containing the axis of rotation, or within a plane parallel thereto;
• and
• (iii) a transition section in which the interfacing cut line transitions from the first length to the second length.

An aircraft comprising a wing, the wing having a fixed wing with a wing tip device moveably mounted at an outer end of the fixed wing, 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 a span of the aircraft wing is reduced from the flight configuration,
• wherein the wing tip device is rotatable between the flight and ground configurations, about an inclined axis of rotation, such that the wing tip device rotates upwards and rearwards when moving from the flight to the 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 of the wing tip device,
• the interfacing cut line comprising a leading edge section passing over an upper surface of the wing, through a leading edge of the wing and onto a lower surface of the wing, the leading edge section of the cut line being formed by a cut that extends within a plane containing the axis of rotation, and
• the interfacing cut line comprising an upper surface section located on the upper surface and extending through the axis of rotation and being offset inboard from the plane containing the axis of rotation;
• and
• the interfacing cut line comprising a lower surface section located on the lower surface to the rear of the axis of rotation and being offset outboard from the plane containing the axis of rotation.