One of the drawbacks of the Sonex is, without doubt, its limited range, which reduces the opportunities to undertake long journeys safely. This simple and safe system was designed to increase the range of the Sonex, Waiex  and Xenos aircraft in a 50%. 

 

The first prototype has been tested over a period of one year in the Sonex SN880 during which the tank has been filled 23 times with no problems during the transfer of fuel to the main tank. The only modification from the original design is that the internal walls are now riveted to the external structure to increase the strength.

 

The installation of the auxiliary tank does not alter the plane’s centre of gravity beyond the permitted range even when the plane is fully loaded, with two occupants, baggage and full fuel tanks.