Loss of Control in Flight · NTSB WPR13FA022
BEHNE GLASAIR III — Byron, CA
| Date | October 23, 2012 |
| Location | Byron, CA |
| Aircraft | BEHNE GLASAIR III (amateur-built) |
| Purpose of flight | Personal |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Maneuvering Loss of control in flight |
| Pilot age | 57 |
| Pilot total time | 3,457 hrs · High time |
| Time in type | Unknown |
| Fatalities | 2 |
Probable cause
NTSB findings
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-(general)-Not attained/maintained - C
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
- Personnel issues-Physical-Impairment/incapacitation-Illicit drug-Owner/builder
What happened
The two pilots, one of whom owned the airplane, departed for a personal flight. The airplane was equipped with dual flight controls; however, it could not be determined which pilot was manipulating the controls at the time of the accident. Witnesses located adjacent to the accident site reported that they heard a loud noise and then saw the airplane slow down and begin to spin left in a slight nose-low attitude. The witnesses further reported that the airplane continued to spin until it impacted terrain. Postaccident examination of the engine and airframe revealed no evidence of any preexisting mechanical anomalies that would have precluded normal operation. Wreckage and impact signatures were consistent with a flat-spin, slightly nose-low impact with terrain.
Postmortem toxicology tests for the left seat pilot/owner were positive for doxylamine (an antihistamine used in over-the-counter sleep aids and cough medicines) and methamphetamine (a central nervous system stimulant). Because the amount of doxylamine in his system at the time of the crash was below the therapeutic limit, its direct effects on the left-seat pilot's performance at the time of the crash could not be determined. Although methamphetamine was present in the left-seat pilot's blood, the amount was below the calibration limit of the toxicology tests. However, both methamphetamine and its metabolite (amphetamine) were present in his urine. Regardless, no direct correlation exists between the concentration of drug in the blood and the user's symptoms. Although it is unlikely that the left-seat pilot was actively euphoric at the time of the flight, he was likely in the late phase of symptoms or in the withdrawal phase(during which concentrations of the drug may be undetectable), which would have been impairing. However, as noted, it could not be determined which pilot was manipulating the controls at the time of the accident; therefore, the impact of the left-seat pilot's drug impairment on the flight could also not be determined.