This December 2009 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Aircraft: Piper Twin Comanche. Injuries: 2 Fatal. Location: Port Mansfield, Texas. Aircraft damage: Destroyed.
What reportedly happened: The commercial pilot and his passenger departed on a four-hour VFR cross-country flight that had them arriving at an oceanside airport at night. Since the destination airport did not have any weather reporting capability, the pilot had to rely on weather from an airport 23 miles away and further inland.
The weather conditions deteriorated while en route. The ceiling dropped to 1,000 to 1,200 foot overcast, the visibility 9-10 miles, and the temperature/dewpoint spread were converging, so the pilot filed an IFR flight plan with air traffic control. As he approached his destination, the pilot asked ATC if he could descend to 2,000 feet and “take a look.” The controller approved the descent at the pilot’s discretion. ATC later cleared the pilot for a visual approach since no instrument approach procedures were available for the airport.
The pilot was instructed to descend to 1,600 feet and to report when the airport was in sight. The pilot acknowledged that he had the airport in sight and there were no further communications with him. Radar data revealed the airplane flew southeast toward the airport at an altitude of 800 feet, then flew beyond the airport before it made a left turn toward the shoreline. The last recorded altitude was 600 feet. A witness who lived near the airport heard the airplane flying low over his home and went outside, but he was unable to see the airplane due to heavy haze. He said the airplane noise traveled toward the shoreline and disappeared.
The airplane came to rest inverted in approximately 7-10 feet of water about 1.6 miles east of the airport. Damage to the airplane was consistent with a shallow impact angle with the water, the subsequent recovery operations, and salt water corrosion. All four blades exhibited bending and twisting toward low pitch, consistent with water impact at low or moderate power. The landing gear was extended and the flaps were fully retracted.
Probable cause: The pilot’s failure to maintain clearance with the water while on approach to land.
For more information: NTSB.gov; NTSB Identification: CEN10FA070