Emirates Spinnaker Tower two large, white, sweeping metal arcs, which give the tower its spinnaker sail design. The steelwork was fabricated by Butterley Engineering. At the top is a triple observation deck, providing a 360° view of the city of Portsmouth, the Langstone and Portsmouth harbours, and a viewing distance of . The highest of the three observation platforms, the Sky Deck, has only a wire mesh roof, so visitors are open to the elements. The windows extend above head height, so it is not possible to get a view unobstructed by glass. A glass floor is located on the first viewing deck
Spinnaker the spinnaker is attached the top of the sock and the ring runs down to the tack. The resulting bundle is stuffed into the spinnaker bag. The top of the sock will have provisions for attaching to the spinnaker halyard. The spinnaker is raised as normal, but with the sock in place the spinnaker is unable to catch the wind. Once the spinnaker is raised and the guys are ready to set, the sock is raised, releasing the spinnaker. The sock remains bundled up at the head of the sail while the spinnaker is deployed. To retrieve the spinnaker, the