Mechanism for use in moving a wing tip device

An aircraft having a wing (120, figure 3) comprising a fixed wing (126), a wing tip device 250 and a wing tip mechanism 260 moving the wing tip device relative to the fixed wing. The wing tip mechanism comprises a wing tip actuator 262 (for example a linear actuator such as a screw jack actuator 262) and a latch 272 and latch trap 274. When the latch is latched by the latch trap the wing tip device is movable relative to the fixed wing under the control of the wing tip actuator, and when the latch is unlatched the wing tip device is released from the control of the wing tip actuator. In the unlatched state the wing tip can move under the action of aerodynamic forces exerted on the wing tip to provide passive load alleviation on the wing. The wing may be moved from a latched state to one of a flight configuration and a ground configuration. The latch may comprise a spring-loaded pin which is held in a recess 274 when the actuator 262 is in an engaged configuration.