The Grand Prix Hydroplane has a maximum boat size of 8.0m long by 3.81m wide and the “box style” method of measurement must be used (i.e. the boat plus all projections must fit into a rectangular box 8 metres by 3.81 metres. All boats must weight at least 910kg's for unsupercharged and 1080Kg's for suercharged engines
Engines must be cast iron automotive or marine 4-cycle, 2 valves per cylinder, internal combustion type with a maximum capacity of 8.36 litres (510ci) with no allowance.
Superchargers and turbo chargers are permitted, without penalty
Visually impressive at top speeds they have a wall of water 100 feet high and 500 feet long behind them with as much as 3 tonnes of water in the air. This wall of water drops slightly as they go into a corner but instantly reappear as the boat enters the turn and the turn fin struggles to hold the boat in the corner.
These boat travel at top speeds of 280kph and are the fastest automotive engined boats on the circuit.
The rules for GP Hydroplanes require that they have a Driver Safety Capsule for each boat; in the Capsule, there is a five-point safety harness or seatbelt and onboard air supply for the driver. The air supply tank is mounted in the hull or on the driver, it also has a disconnect fitting that will allow an emergency diver to connect an additional air supply.
Each capsule must have a hatch in the bottom to allow a driver to get out if the boat flips over, this hatch is painted International Orange, also a removable steering wheel to allow greater emergency access.
GP Hydros are fitted with a fire suppression system that when activated will spray fire suppressing agent into the engine compartment. This system can be triggered from inside the cockpit or from outside, the letter E in a red circle indicates the outside trigger location.
GP Drivers are to ensure that the Emergency Divers have inspected their boat prior to racing.
What is a Hydroplane?
By definition a boat with two or more planning surfaces. In modern hydroplanes these are of the "three point" design with sponsons that protrude from the sides of the hulls at the front, on which the boat rides and the propeller that pushes the back of the boat from the water. This being the 3 points, 2 sponsons and the propeller.
The air rushing under the boat help to support it at speed and compared to "normal boats" these is very little drag resistance offered allowing the highest possible speeds to be obtained.
Hydroplanes use the principle of 'ground force"
Some hydroplanes even have the centre section designed just like an aircraft wing to help them glide thru the air and only barely in touch with the water.
