The SeaBreacher uses a 300-lb. Atkins 13B rotary marine engine that generates 175 hp (a 240 hp super-charged version is also available). The aluminum Hurth V-drive transmission with a 2:1 gear reduction lets the prop be lower and further forward under the hull to give pilots greater balance. The engine allows for speeds of 30 mph above the surface and 20 mph below. The vehicle can only go a few feet under the surface because when the snorkel (in the dorsal fin) is submerged, the engine's fresh air supply is cut-off and the engine looses power. SeaBreacher has a taller, larger snorkel for deeper dives and greater airflow than its predecessor. The snorkel's automatically closing butterfly valve prevents water from getting in during deeper dives. A removable video camera pod mounts on top of the snorkel to let the pilot view the surface on a dash-mounted LCD.
A redesigned control system that increases the performance and simplicity for novice pilots lets the submersible pitch straight down and pop up backwards and porpoise like a dolphin. Operation of the main wings remains the same, with two independent hand-operated controls but the rear control surfaces have switched from a V-tail (ruddervators) to a more conventional independent rudder and elevator setup. The rudder and elevators are both operated with a new foot pedal that pivots left and right on one axis and up and down on another axis.
Keeping the vehicle afloat and water tight was a top priority. Both the cabin and engine bay are sealed watertight with pneumatic aircraft seals. Three bilge pumps are on board in case a rogue wave swamps the interior while the canopy is open. The hull also contains enough flotation to keep the craft afloat and upright even if fully loaded. The canopy is the same as that used by the F-22 Raptor aircraft, 3/4-in. thick polycarbonate. And both the pilot and the passenger are secured with four-point safety harnesses.
The prototype was built using vinylester and fiberglass with a Nidacore PVC honeycomb core. The hull was built first to maintain the sleek style of the submersible. Designers installed all the hardware and the pilot and passenger seats to have all the necessary measurement constraints. The body was then sculpted to match the new flare-sided canopy and lower hull section. The SeaBreacher's hull resembles a more conventional deep V design to increase surface performance and reduce the amount of water spray while planeing and long inward cutouts behind the main wings minimize main-wing spray.
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