QUICKSILVER SPT 2S N5593F accident near Lajas, Puerto Rico

Probable cause

The pilot’s failure to maintain adequate airspeed, which resulted in an aerodynamic stall and entry into a spin.

NTSB analysis

The non-certified pilot departed for a local flight and, during cruise flight, a witness reported seeing the airplane in a nose-low attitude spinning two times before impacting the ground in an open field. A postaccident inspection of the airframe revealed no evidence of preimpact failure or malfunction. The engine was started without a propeller and the engine and engine systems were found to operate normally. Results of postmortem toxicology testing were consistent with the regular use of a prescription antidepressant and relatively recent use of two different prescription medications that may be used for anxiety or as sleep aids. The investigation considered the possibility that the pilot may have been impaired by the recent use of an anti-anxiety medication or by the conditions for which the medications were prescribed; however, the role of any possible impairment in the accident could not be conclusively determined.

Text from the NTSB. Open the NTSB docket for ERA11LA056 for the full record.