The H1 Unlimited (prior to the 2009 Oryx Cup, known as ABRA Unlimited (American Boat Racing Association) since 2004) class is sanctioned by APBA, its governing body in North America and UIM, its international body.
Unlimited Hydroplanes are fast boats capable of 200+ MPH on the straightaways and running average lap speeds from 130-165 MPH. They are 28–30 feet in length and weigh a minimum of 6750 pounds (3062 kilograms).
The modern turbine-powered unlimited hydroplane is derived from the 3-point prop-riding hydroplanes of the 1950s. These were the first boats to ride on a cushion of air trapped between "sponsons" mounted on the sides of the front of the boat, and the bottom half of the propeller, which were all that touched the water.
They were called "Unlimited" because they were the only class of boat racing the APBA that had no restrictions on the displacement size of their piston engines. The designation Unlimited has stayed with the class in the turbine era, even though there are restrictions on the turbine engine and its fuel.
The Lycoming T55 L7C, originally used in Chinook Helicopters, is the only turbine engine currently allowed in the sport.
Famous quotes containing the word unlimited:
“They that have grown old in a single state are generally found to be morose, fretful and captious; tenacious of their own practices and maxims; soon offended by contradiction or negligence; and impatient of any association but with those that will watch their nod, and submit themselves to unlimited authority.”
—Samuel Johnson (1709–1784)