In contrast , headwinds met a nearly vertical cabin entrance , which acted as a large sail fighting against the paddlers .
When the winds blew from behind , the cabin presented a smooth , aerodynamic shape which reduced the tailwind advantage .
Headwinds met a nearly vertical cabin entrance , which acted as a large sail fighting against the paddlers .
When the winds blew from behind , the cabin presented a smooth , aerodynamic shape which reduced the tailwind advantage .