Originally Posted by
cheekymonkey
I look at the winglets (when available) for Boeing 737-x vs Airbus A319/20/21.
I'm sure someone will correct me if I'm wrong, but Boeing 737s "always" have no winglets, or winglets that extend above the wing. Airbus A319/20/21 have "mini" winglets that extend above and below the wing.
True. Boeing does winglets that only rise, while Airbus does go above and below, and they are called "wingtip fences".