U-100:| Anatomy | Vital Data | Fun Stuff |:U-100

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An extension of the inside "wall" that forms the boat's tunnel. Changing the length of the airtraps changes the hull's ride.


Adjustable wings on the leading edge of the deck. They change the flow of air over-and-under the hull, which in turn changes the lift of the hull.


A fully enclosed "safety capsule" designed to protect the driver in the event of an accident.


The hood that covers the engine compartment and improves the boat's aerodynamics.


The upper surface of the hull.


The motor that provides the power. In the past, the primary engines used were large 12-cylinder Rolls-Royce airplane engines. These days, almost all of the hydros use turbine (jet) engines. The PICO American Dream powerplant is a Lycoming T55L7C Turbine capable of producing over 3,000 horsepower, which will turn a drive shaft and three-bladded PICO propeller in excess of 15,000 RPM. The fuel burned by these engines is aviation jet fuel or "Jet-A".


The main body component of the boat. In Unlimited Hydroplane Racing, the hull must be at least 28 feet in overall length.


The vertical surface of the hull which is inclined to aid in cornering.


The front cowling. Its aerodynamic shape deflects the air around the cockpit and engine compartment.


Also called simply the "prop", the propeller is the component that actually moves, or "propells" the boat. Propellers used in hydroplane racing may have two or three blades. Many of the propellers used in racing can cost upwards of $10,000 to $15,000 each.



The shaft that transmits the power from the engine back to the propeller.


A blade near the transom which sticks into the water and causes the boat to turn.


The surface that touches the water at the bottom of each sponson.


The fitting on the bottom of the hull through which the prop shaft passes.



The blade attached to the inside sponson. It helps keep the boat from sliding to the right as it makes a turn.



The two pontoon-like parts at the front of the hull. When there is no deck between the sponsons, as in this photo, the design is called a "pickle-fork".


The rear bearing for the prop shaft.


Vertical pieces which support the wing and provide directional stability.


The vertical surface across the back of the boat.


The space beneath the hull proper and between the sponsons and airtraps. The tunnel creates a cushion of air on which a hydroplane travels.


The horizontal airfoil that helps stabilize a boat's attitude.

U-100:| Anatomy | Vital Data | Fun Stuff |:U-100