Duck-under syndrome kills three

Aircraft: Piper Aztec. Injuries: 3 Fatal, 1 Serious. Location: Charlotte Amalie, Va. Aircraft damage: Destroyed.

What reportedly happened: There was no record of the pilot obtaining a weather briefing before the flight or filing a flight plan. The destination airport was tower-controlled, but the tower was closed at the time of the accident. The runway was located along the shore, with the approach end surrounded by water on three sides.

The airplane was flying  over water on a dark night at an altitude of about 1,700 feet above the surface. Radar data showed the airplane in a gradual descent before it leveled off at 200 feet above the water. The airplane continued at 200 feet above the water for another 18 seconds before its radar target disappeared about five miles from the destination airport when the airplane hit the water.

The surviving passenger stated that she had flown the route with the  pilot many times before. She noted that during the accident flight, the pilot flew progressively lower to “get under the weather.” She could see lights on the shore near the destination airport, and could see that it was raining. She recalled light turbulence and observed the pilot make his “usual” radio call.

She next remembered the airplane “hitting a wall,” and the airplane filled with water. She said that the pilot broke the window on his side of the airplane, and that she and the pilot went through it. She did not see any of the other occupants of the airplane after that.

Examination of the wreckage revealed damage consistent with a high-speed, shallow-angle impact with water, and no evidence of pre-impact mechanical anomalies.

Weather data and imagery were consistent with the passenger’s account of flying beneath outer rain bands associated with a developing tropical storm southeast of the accident site. There was little to no illumination from the moon.

Multiple instrument approach procedures were available for the airport, however, those instrument approaches were not authorized while the tower was closed. A caution printed in the plan view of the approach charts stated, “CAUTION: Pilots may encounter false illusory indications during night approaches to Runway 10 when using outside visual cues for vertical guidance.”

Probable cause: The pilot’s attempted visual flight rules into marginal VFR conditions on a dark night over water and his failure to maintain sufficient altitude, which resulted in the airplane’s controlled flight into water. Contributing to the accident was the pilot’s inadequate preflight weather planning.

NTSB Identification: ERA13LA019

This October 2012 accident report is are provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.