One disadvantage of earlier Ground Effect Craft was the fact, that the take off from water required by far more engine power, than the operation in Ground Effect during cruise.
![](images/bild_tech_ht_2.jpg)
To make Ground Effect Craft commercial feasible, one of the most important targets was to reduce this take-off drag by having a take-off-aid.
The R&D work of Fischer Flugmechanik were heavily sponsored by the German Ministry for R&D (BMB+F)and led to an air-cushion supported design, in which a part of the propeller slip-stream is taken during take-off, and guided under the Katamaran fuselage to build up a static air cushion, which creates already 80% of the crafts weight as lift, while speed is still 0.
Further advantage of the Hoverwing Technology is the fact, that after take-off, the air inlets behind the propellers are closed, and the full thrust is available for cruise.
Thus the Hoverwing Technology is the bridge between ACV and WIG craft.