What happened
On January 14, 2024, a Cessna 310R, registration N252DL, was involved in a fatal accident near Poolville, Texas. The flight was an instrument flight rules (IFR) cross-country trip from Carrizo Springs Airport (CZT) to Bridgeport Municipal Airport (XBP).
Before departure, the pilot reviewed a weather briefing that included AIRMETs for moderate icing and forecasts for freezing drizzle and ice pellets. While cruising at 7,000 feet, the pilot inquired about icing reports, and air traffic control (ATC) reported trace rime ice at higher altitudes. At 12:04, the pilot was cleared to descend to 3,000 feet. Shortly after, the pilot ceased responding to ATC communications. Despite repeated attempts by the controller to contact the aircraft and the issuance of low-altitude alerts, there was no reply.
Flight track data showed the aircraft began a steady descent of 600 to 750 feet per minute from 7,000 feet, maintaining a heading of approximately 016° for about 10 minutes until it struck the ground. A witness observed the airplane flying at a low altitude, level and above the tree line, with the landing gear retracted and propellers rotating.
The investigation
The investigation examined the wreckage, which was spread over 370 feet in a wooded area. The fuselage, wings, and empennage sustained post-impact fire damage. While the aircraft was originally delivered with pneumatic and electric de-icing boots, no anti-icing or de-icing systems were observed in the wreckage. Maintenance records indicated that the required 24-month inspection for the transponder, altimeter, and pitot-static system had not been completed.
An autopsy of the pilot revealed moderate coronary artery disease. While ethanol was detected in the vitreous fluid and urine, investigators noted that such findings can occur postmortem. The presence of the antihistamine cetirizine was also noted, though its impact on the pilot's state could not be determined.
Findings
- The aircraft was likely flying in instrument meteorological conditions (IMC) through moderate or greater icing with supercooled large droplets during its descent.
- The wreckage distribution and witness accounts were consistent with controlled flight into terrain.
- The pilot's coronary artery disease presented a risk for a sudden cardiovascular event that could cause incapacitation.
- There was no evidence of a mechanical failure in the flight controls or engines that would have prevented normal operations.