Winglets at Newcastle Airport

I noticed that our aeroplane had upturned wingtips. These are called winglets and are used to reduce the vortices that are formed at the tips of the wings. You can see these vortices in certain atmospheric conditions. There is a pressure difference between the air masses below and above the wing and this difference cause mini-hurricanes. Looking up this topic reveals the drag factors on aeroplanes to be very complicated so more research needed.