The "Air around the spinner" design is perfect for the Viking liquid Cooled engine.  Those that implement this design benefit from the following:  

  • Plenty of cool air for the engine air filter.  (Eliminating the need for a separate NACA air inlet)
  • Plenty of air to cool the reduction drive unit
  • Plenty of air to reduce under cowl temperatures, increasing the life of all components.
  • Good looks
  • Aerodynamically Efficient