Amateur-built Lancair Legacy N151HT accident near Parowan, Utah

Probable cause

The pilot failed to secure the canopy prior to takeoff, resulting in his inability to control the aircraft during the takeoff. Contributing to the accident was the pilot’s impairment from prescription medications and possible obstructive sleep apnea.

NTSB analysis

During departure, witnesses in the area reported that the airplane appeared unusually low and then entered a left turn. As the airplane entered the turn, items from the cockpit fell from the airplane. The airplane continued in the left turn until it impacted the ground. Examination of the wreckage revealed no evidence of preimpact mechanical malfunction. The airplane, by design, does not have a cockpit indication for the security of the canopy. Structural documentation of the canopy latching mechanism did not reveal any damage to the latching mechanism, which is indicative of it not being latched when the airplane impacted the ground. Based on post-mortem toxicology results, the pilot had likely recently used two different prescription painkillers that commonly result in impairment, and that may increase risk of seizure, particularly when used together. Based on his height and weight, poorly controlled blood pressure in spite of the use of at least two different medications to lower it, and the presence on autopsy of right-sided heart enlargement, he likely had obstructive sleep apnea, a condition associated with fatigue and cognitive impairment. His response to a real or perceived emergency may have been impaired by the medications themselves, by a seizure induced by the medications, or by the effects of possible obstructive sleep apnea. The pilot did have a single blocked small coronary artery, but the condition had been present and evaluated just over two years prior to the accident, with evidence of good blood flow in spite of the blockage. It is unlikely that the blockage was related to the accident. The pilot had not indicated high blood pressure, use of medications to treat high blood pressure, or use of prescription painkillers on his most recent application for airman medical certificate just over 16 months prior to the accident.

Text from the NTSB. Open the NTSB docket for WPR09LA016 for the full record.