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 accepted term spinnaker. Gordon was widely known in the yachting world of the time as 'Spinnaker Gordon.' It has been pointed out, however, that the skippers of Thames sailing barges also used the term "spinnaker" for their jib staysails. Unlike the other, tanned sails of these boats, the "spinnakers" were usually of white color. It has thus been suggested that the term could be "connected with the obsolete word "spoon", meaning to "run" before the wind (cf. "spindrift")." Early usage of the verb "to spoon" can be traced back to the 16th century; the change from "spoon" to "spin" in