On July 6, 1996, at 1821 hours Hawaiian standard time, a Piper PA-28-181, N4319J, ditched at sea 3 miles south of Lanai Island, Hawaii, following fuel exhaustion. The aircraft was operated by Cosmo Flying School of Honolulu, Hawaii, and was rented by the pilot for an inter-island personal cross-country flight. Visual meteorological conditions prevailed at the time and no flight plan was filed for the operation. The aircraft sank and is presumed to be destroyed. The certificated commercial pilot and his one passenger were able to exit the aircraft and were picked up at 2139 by a passing boat. The flight originated at Honolulu on the day of the accident at 1313, and made en route stops at airports on the islands of Molokai, Maui, and Hawaii. The last departure point was from Hilo, Hawaii, at 1642. According to the pilot's oral and written statements, he departed Honolulu with full fuel tanks (48 useable gallons) and flew to Kalaupapa airport on the island of Molokai, where a full stop landing was made. About 15 minutes later, he departed and flew to Hana airport on the island of Maui, where another full stop landing was made. The aircraft was on the ground for 40 minutes, then departed for Hilo on the island of Hawaii, arriving 47 minutes later at 1530. After 25 minutes on the ground, the flight departed Hilo for a nonstop return to Honolulu over a direct route (see attached chart). The pilot stated that while on the ground at Hilo he estimated the fuel used to that point at 26 gallons, and further estimated that the remaining 22 gallons were sufficient to "easily be able to fly back to Honolulu and have a 30 minute reserve." In his written statement, the pilot said that about 1803 (1 hour 20 minutes into the return flight) he noticed that the left fuel gage was decreasing rapidly and immediately checked the aircraft exterior for signs of leakage and found none. With the fuel selector on the left tank, the engine began to lose power and the pilot switched to the right tank, then contacted Honolulu CERAP. ATC communications tapes disclose that the pilot contacted Honolulu CERAP at 1803, declared a low fuel state and requested radar vectors to the nearest airport. The controller provided a heading to an airport on the island of Lanai, about 27 miles distant. At 1816, the engine lost all power and the aircraft was forced to ditch in the ocean at the radar estimated coordinates of 156 degrees 55 minutes west longitude by 20 degrees 42 minutes north latitude. The pilot and passenger exited the aircraft into the water before it sank and were picked up 25 minutes later by a passing boat. Takeoff and landing times at the points on the pilot's itinerary were obtained from information supplied by various FAA Air Traffic Control facilities, the U.S. Navy Fleet Air Control and Surveillance radar network for Hawaii, and from the pilot's statement. The information and times were compiled into a table, which is appended to this report along with all referenced primary documentation. Review of the table discloses that 5 hours 3 minutes elapsed from the time the pilot departed Honolulu until the accident. Of that total time, 3 hours 43 minutes was flight time, and 1 hour 20 minutes was ground time. The pilot did not have floatation or survival gear onboard the aircraft. The water depth at the accident site is in excess of 600 feet and the aircraft has not been recovered.