Envira-North Systems Ltd.  has launched the latest and most efficient technology available for the large industrial HVLS ceiling fan market.  

The Altra-Air Sailfin variable pitch, modulated trailing edge airfoil removes the inefficiencies created by differentiating rotational HVLS fan speeds.  Simply put- a faster tip speed requires less surface area and less angle of attack to produce airflow.  While a slower hub speed requires more surface area and more angle of attack to produce airflow.  The evenly spread deflection creates less disruption in the trailing air stream, producing cleaner air for the following airfoil, less blade flex in the alternating blade assembly and lowers unwanted ( and expensive ) operating load.  

All this adds up to greater air speed velocities with less noise created and less money spent operating....not to mention one sleek looking design!.