Hi WF,
I thought winglets worked by reducing the drag of the wingtip vortex, and this is how they improve efficiency?
Do they really produce thrust from the vortices as well? Can you explain how? I am not having a go, I am genuinely curious.
I would imagine that the increased vertical area of the winglets would affect crosswind performance - they are large vertical surfaces which would generate more sideways force from the crosswind than an aircraft without them?