On March 30, 1997, about 1745 Atlantic standard time, a Piper PA-32-260, N576PR, registered to a private individual, was ditched in the Atlantic Ocean about 5 nautical miles northwest of the Island of Vieques, Puerto Rico. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 positioning flight. The airplane was presumed to be substantially damaged and was not recovered and the airline transport-rated pilot, the sole occupant, was not injured. The flight originated about 1715 from the Luis Munoz Marin International Airport, San Juan, Puerto Rico. The pilot stated that while descending for approach to land, the engine experienced a total loss of power. Unable to land at the destination airport he ditched the airplane. At the time of the loss of engine power he reported having 3.5 hours of fuel on-board. The airplane was not recovered; therefore, the reason for the loss of engine power could not be determined.