Hinge
I posted pictures from a similar ‘plane from Duxford a while ago. This one is from PIMA and shows the hinge that allows the wings to be swept back for storage on an aircraft carrier. There is a single axis hinge and one flap that falls down to accommodate the movement and then come back together with a continuous aerodynamic surface. It must have taken some working out – I wonder if this was done through drawings or models?