sentences:  Vought V-173
  
  The Vought V-173 "Flying Pancake" was an American experimental test aircraft built as part of the Vought XF5U "Flying Flapjack" United States Navy fighter aircraft program during World War II.Both the V-173 and the XF5U featured an unorthodox "all-wing" design consisting of flat, somewhat disk-shaped bodies (hence the name) serving as the lifting surface.