Stall / Spin · NTSB WPR21FA170
CONSOLIDATED VULTEE BT-13A — Camas, WA
| Date | April 21, 2021 |
| Location | Camas, WA |
| Aircraft | CONSOLIDATED VULTEE BT-13A |
| Purpose of flight | Instructional |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Initial climb Aerodynamic stall/spin |
| Pilot age | 69 |
| Pilot total time | 274 hrs · Low time |
| Time in type | 177 hrs |
| Fatalities | 1, 1 serious |
Probable cause
NTSB findings
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Angle of attack-Capability exceeded
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Student/instructed pilot
What happened
The flight instructor was providing recurrent training to the pilot in the tailwheel-equipped airplane. They had completed several takeoffs and landings at a nearby airport before returning to the departure airport. The first approach to the runway resulted in a go-around due to an unstable approach, and following the second approach, the pilot receiving instruction performed a three-point landing. During the landing roll, the airplane veered left and exited the runway, and the pilot applied full power and “immediately pitched up.” The airplane climbed in ground effect to about 30 ft, then entered a left turn, and its bank angle continued to increase before the airplane impacted terrain. The airplane came to rest adjacent to a hangar in a nose-low, near-vertical attitude. The pilot was fatally injured. The instructor added that, although he had been guarding the flight controls, due to the low altitude of the event, he did not have time to react before impact.
Toxicology testing of the pilot receiving instruction detected diphenhydramine, a sedating antihistamine commonly available over the counter in a host of preparations intended to treat cold and allergy symptoms and to induce sleep. The range of levels where effects are expected are above 25 ng/ml, but the drug undergoes significant post-mortem redistribution and levels found in cavity blood likely do not accurately reflect antemortem levels.
Although the pilot receiving instruction could have been impaired somewhat by the effects of a small amount of diphenhydramine in his system, some of those effects would have most likely been overcome by the adrenalin naturally produced in the emergency situation. It is therefore unlikely that the small amount of diphenhydramine contributed to the accident circumstances. The accident is consistent with the pilot’s exceedance of the airplane’s critical angle of attack during an aborted landing, which resulted in an aerodynamic stall and impact with terrain.