Hydroplane Diagram


Rudder - Helps steer the boat, has a water intake for the motor

Prop - 3 blade prop, 1 blade is in the water at a time, the blades create the wall of water behind the boat known as the "roostertail" by throwing the water up in the air as it exits the water (though the boat runs a turbine jet engine the propeller does "push" the boat through the water)

Uprights & Horizontal for the tail section, aka stabilizer & "tail feathers" - Helps to provide lift to the rear of the boat, while also improving the ride

Cowling, aka engine cover or air intake - Keeps the turbine engine & the gear box from being doused with water, air intake opening provide air to the motor

Sling - Nylon straps used to lift the boats off the trailer & into the water then out of the water & back on the trailer

Cockpit - Fully enclosed cockpit similar to a fighter jet, canopy raises to allow the driver to enter/exit the boat, protects driver

Canard, aka front wing - Helps to adjust the ride of the boat and allows more air to pass over the boat or forces more air under the boat, moved by foot pedals at the driver's feet

Sponsons, aka pickle forks - Main area of the boat that "touches" the water

Air trap -Open area between the sponsons, forms a pocket of air that the boat rides on

Hydro Facts & Info

1) The unlimited hydroplanes have been racing since about 1906.

2) The hydros run T-55 L7C Lycoming Turbine engines.

3) They typically use Jet-A fuel but can use kerosene.

4) Only 3 areas of the boat should touch the water at any given time. They are 2 handkerchief size areas on the back of the sponsons & 1 in the back area known as the transom (basically it's the area of the hull above the prop).

5) Currently (2008) there is 1 salt water race, San Diego. Salt water is especially bad on the turbines so each team has what is commonly know as a "salt water scoop". This is essentially a long tube that connects to the air intake (opening at the front) of the cowling. This longer air intake extends over the canopy, thus avoiding the salt water spray as the boat accelerates from a stop (aka "spooling up") or decelerates (like when returning to the docks).

6) The boats average around 150+mph on most courses and usually hit 200mph in the straightaways.

7) Every boat is required to have a canopy. Because the boats can land upside down after an accident they are also required to have an escape hatch in the floor of the cockpit.

8) The steering wheels on all boats are removable to allow the driver to enter & exit the cockpit.

9) The driver wears a headset radio to communicate with their crew on the beach.

10) The boats are made from molds using carbon fiber and honeycomb aluminum.

11) Most skid fins are so heavy that teams must use a crane to change them!

12) The boats use a reduction gearbox to "gear down" the turbine engines in order to turn the prop.

13) Without a skid fin the boats cannot turn. The rudder alone is not enough due to the high speeds & G's pulled in the turns.

14) The drivers breathe compressed air while running.

15) The roostertail is the wall of water kicked up behind the boat by the prop. This massive amount of water is a danger to other drivers and can cause serious damage to boats that accidentally go through it.