Low-Altitude Maneuvering · NTSB CEN09LA427
ZIVKO AERONAUTICS INC EDGE 540 — Tarkio, MO
| Date | July 10, 2009 |
| Location | Tarkio, MO |
| Aircraft | ZIVKO AERONAUTICS INC EDGE 540 |
| Purpose of flight | Air Race/Show |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Maneuvering-aerobatics Collision with terr/obj (non-CFIT) |
| Pilot age | 36 |
| Pilot total time | 1,700 hrs · Experienced |
| Time in type | Unknown |
| Fatalities | 1 |
Probable cause
NTSB findings
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot - C
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-(general)-Not attained/maintained - C
What happened
The aerobatic airplane impacted the ground following a loss of control during an practice flight. The pilot was an aerobatic performer who was scheduled to perform at an airshow the following day. Video of the accident flight showed the airplane in a climbing vertical roll which was followed by what appeared to be an inverted spin. The rotation of the spin was halted with the airplane in a near vertical descent. During the recovery from the dive, the airplane suddenly rolled to the right and rotated about 1-1/2 turns before impacting the ground in a nose-low, right-wing-down attitude. Audible engine sounds were present throughout the recording. An examination of the airplane failed to reveal any pre-impact deficiencies with regard to the airplane’s structure, flight control system or other airplane systems. The pilot had been intermittently prescribed a prescription stimulant for weight loss approximately 2-3 years prior to the accident and had not indicated the use of the medication to the FAA at that time. The medication was found on post-mortem toxicology testing, suggesting use within the several days preceding the accident, but the nature of the specimens tested did not permit more accurate estimation of when it may have last been used or whether the pilot may have been impaired by such use. Given the challenging maneuvers being performed, even slight impairment may have been sufficient to contribute to the accident.