1973 APBA Gold Cup

Will It Revolutionize Unlimited Hydroplane Racing?

Unlimited hydroplane racing, revolutionized by the introduction of surplus World War II airplane engines, may enter a new era, powered by Viet Nam helicopter turbines.

Twin Lycoming T-53 turbine power plants, just like those used on whirlybirds in Indochina, will be used in a new unlimited boat that hopefully will make its first start in the Gold Cup.

Owner Jim Clapp of Seattle is gambling about $250,000 that the turbine theory will work.

A variety of exotic equipment being developed should make it the most innovative unlimited ever built.

Leif Borgersen, the driver, has learned to fly just so he can communicate more effectively and better understand the systems involved. Tape will be used to monitor the readings of the 22 different systems needed to operate the boat. If something goes wrong, the tape can be played back on shore to check the source of the problem.

A stability augmentation system similar to that used on aircraft, which responds quicker than a driver could, will be used to control the hydro if it gets out of proper attitude.

Project manager is Chuck Lyford, longtime boat and airplane racing enthusiast. The builder is Ron Jones and the hull design is similar to the Pride of Pay ‘N Pak and duplicated in Notre Dame. The driver will lie in a semi-reclining position. The boat will be about 800 pounds lighter than Jones latest effort, Pay ‘N Pak.

The U-95, as yet unnamed, is designed so that the speed of the boat will have to be varied as little as possible. This means a maximum of 150 MPH down the chute and an average of 130 MPH — which would be a record on any course in the country.

Conventional hydros run faster on the straightaway but wallow through the turns.

Deceleration is a turbine problem because unlike piston engines, there’s little "drag." With turbines, it’s critical to keep engine RPM’s high for performance. Spoilers will be used to slow the boat down aerodynamically while keeping up the engine RPM’s. The spoilers are deck mounted and can also be used to change the attitude of the boat and control the ride quality.

Perhaps a new era in unlimited hydroplane racing will begin with the 1973 Gold Cup?

(Reprinted from the 1973 Tri-Cities Gold Cup programme)