Hawker-Beechcraft Corporation A36 N314DP accident near Oklahoma City, Oklahoma

Probable cause

The pilot’s loss of control of the airplane during night instrument meteorological conditions, likely due to spatial disorientation.

NTSB analysis

The pilot flew the night cross-country flight under instrument flight rules in instrument meteorological conditions (IMC). As the pilot approached his destination airport, he reported to the air traffic controller that he had problems with his landing gear indicator. The controller told the pilot to maintain 3,000 feet and turn to a heading of 360 degrees. The pilot acknowledged the instructions; there were no further communications between the controller and pilot. Radar data showed that, as the airplane approached the airport, it was headed generally north-northeast at an altitude of 3,000 to 3,300 feet. The last radar return showed the airplane at 2,600 feet, heading north. Several witnesses reported that they saw the airplane’s red lights appear from the clouds and descend rapidly before the airplane impacted the ground. The wreckage showed damage indicative of a vertical or near-vertical impact. A postcrash fire ensued. Examination of the airplane found no evidence of any preimpact mechanical anomalies.

Postmortem toxicology testing for the pilot indicated positive results for Butalbital, a prescription barbiturate; Citalopram, a prescription antidepressant; Cyclobenzaprine, a prescription muscle relaxant; and Tramadol, which is used for moderate to severe pain. Although such medications can have sedating and/or impairing effects, it was not possible to determine to what extent, if any, the pilot may have been impaired. Both night IMC and the pilot's diverted attention to troubleshooting the landing gear indicator or working the alternate landing gear extension can increase the risk of spatial disorientation, and the airplane’s rapid, near-vertical descent is consistent with pilot spatial disorientation and a loss of airplane control.

Text from the NTSB. Open the NTSB docket for CEN11FA075 for the full record.