19991030045669A

(4)On October 30, 1999, about 2210 eastern daylight time, a Cessna T310R, N4XZ, registered to southern aerial photography inc., impacted with the water about 10 miles north of Key West, Florida. Visual meteorological conditions prevailed at the time, and an IFR flight plan was filed for the 14 CFR part 91 personal flight. The airplane sunk in about 20 feet of water, and was destroyed. The commercial-rated pilot and three passengers received fatal injuries. The flight had departed from the Key West, Florida airport, en route to fort lauderdale, Florida, at 2200. According to air traffic control (ATC) at miami center, at the time the airplane departed from Key West, the ATC tower was closed. The pilot made radio contact with miami center and was advised that he was in radar contact leaving an altitude of 5,500 feet MSL. The controller at miami center observed the airplane in a turn and losing altitude. The controller radioed the pilot and asked if he needed assistance. The pilot answered "standby." Radar and radio contact were lost at 2210. About 0200, a united states coast guard aircraft found debris in the water at 081.46 west and 24.41 north. It was reported, by line personnel a t Key West, that the airplane arrived about noon on October 30, 1999, and was topped off with fuel. Radar data showed that the flight was about to intersect the V157 airway, and was at an altitude of 5,800 feet. The flight started drifting left of the airway and climbed from 5,800 feet to 7,400 feet, reaching 7,400 feet in 2 minutes and 01 second. The airplane turned about 180 degrees to the left, and descended 1,500 feet to an altitude of 5,900 feet, in 47 seconds. The flight continued to descend 4,200 feet, from 5,900 feet to 1,700 feet, in 2 minutes and 36 seconds. The last radar return was at 2209:40, and no altitude was recorded. In addition, the transcript of radio communication indicated that between 2203:04 and 2203:41, the pilot was receiving his IFR clearance. At 2203:41, the pilot read back the clearance incorrectly. The calculated rate of climb from 5,800 feet to 7,400 feet was about 995 feet per minute. The calculated rate of descent from 7,400 feet to 5,900 feet was about 1,915 feet per minute. The calculated rate of descent from 5,900 feet to 1,700 feet was about 1,615 feet per minute. Due to the ocean conditions and high winds the search for the airplane and victims took several weeks. The airplane was not recovered from the ocean until November 15-16, 1999. The accident occurred during the hours of darkness about 24 degrees, 41 minutes north, and 081 degrees, 46 minutes west. (-23) aircraft departed Key West (eyw) on IFR flight plan to ft lauderdale executive airport (fxe) at about 2200 local time. On climbout, miami ARTCC observed a/c depart from on course heading to the northeast. Controller inquired to aircraft to "... Check your heading..." To which PIC responded "standby." No further communications received from a/c. wreckage located by U.S. Coast guard. No survivors found. Mishap occurred at night in apparent VMC conditions. PIC apparently lost control of aircraft for unknown reasons.