On August 9, 2001, about 1215 eastern daylight time, a Piper PA-32-260, N5569J, registered to a private individual, dba Fly Key West, Inc., operating as a Title 14 CFR Part 91 local sightseeing flight, ditched in the Florida Straits, about 41 miles southwest of Key West, Florida. Visual meteorological conditions prevailed and no flight plan had been filed. The commercially-rated pilot received minor injures and was rescued by a Navy helicopter. The two passengers were not found, and the U. S. Coast Guard suspended their search. They are presumed to have drowned. The flight departed Key West International Airport at about 1145. According to the pilot, via telephone conversation with the NTSB, the two passengers appeared to be an older Hispanic couple who spoke little English. Shortly after leveling off at 5,500 feet agl, the male passenger pushed through the collapsible partition that separated the cabin from the cockpit, produced a small knife, turned the communications radio and transponder off, and demanded to be flown to Cuba. In an attempt to thwart the hijacking, the pilot pulled throttle and pushed pitch control to produce enough negative "g" to suspend the passenger on the cabin ceiling momentarily. This action gave him enough time to reverse course to Key West. A struggle ensued that caused the hijacker to fall against the instrument panel, bending the throttle rod, and when the pilot straightened the bend, the rod snapped. With the engine near idle and attempts at increasing throttle setting unsuccessful, the pilot's only alternative was to ditch. The pilot donned his life vest, and the two passengers did likewise, however, they inflated theirs before sea impact. The impact was hard and it appeared both passengers lost consciousness, as they were doubled over at the seat belt and appeared limp, (shoulder harnesses not installed in the cabin). The pilot egressed through the right cockpit door onto the right wing, inflated his life vest, and swam to the left aft cabin door to extricate the passengers. He was not successful in opening the door before the aircraft sank, which occurred within a minute of coming to a stop in the water. (According to a National Geographic Society oceanographic chart, the water depth is about 510 fathoms at 40 miles southwest of Key West). After a period of time estimated by the pilot to be about an hour of the ditching, a U. S. Navy helicopter picked him out of the water. The NTSB sent to the pilot a blank NTSB form 6120.1/2 to complete and return on two different occasions, August 16, and November 19, 2001, by Federal Express delivery, and neither was returned. According to his business partner, the pilot cancelled his cell phone number and relocated to the Jacksonville, Florida area. Numerous attempts to locate the pilot were unsuccessful. According to FAA inspectors, after reviewing all data, listening to the audio tapes of radio transmissions between the FAA Key West Airport control tower and N5569J as the incident was occurring, conferring with the FAA Principal Maintenance Inspector and Principal Operations Inspector for Fly Key West, Inc., who personally interviewed the pilot, no improper operational procedures that contributed or influenced the outcome of this ditching were revealed. As of January 24, 2001, the aircraft or the two rear seat occupants have not been recovered.