surface

"Q-SPD is the first and only commercially produced ALL COMPOSITE Surface Drive System. Q-SPD is available in range of models that can absorb up to 1500hp per drive, high power ability already being designed."

65' Fountain 3000R Twin 1350 HP Caterpillar

"Trimax is a drive system with a surface piercing propeller completely locked in the running position. However, it is possible to set it in the space of a few minutes to obtain the best possible speed. The fixed shaft with the rudder at the rear of the propeller ensures directional...

Weismann Surface Drives http://www.weismann.net/wsd.html

http://www.weismann.net/wsd.html

A diagram of the Power-Vent integrated surface drive system which Gary originally posted in this thread: http://www.boatdesign.net/forums/showthread.php?threadid=672

"POWER-VENT is a patented marine surface drive system designed for high performance boats of any size. Its uniqueness is that it can position high efficiency surfacing propeller technology under the hull of a vessel with more conventional marine hardware and no transom projections.&quot...

A great cutaway view of the best surface drives there are - http://www.arneson-industries.com