Low-Altitude Maneuvering · NTSB CEN17FA016
MAKELA RV-4 — Oregonia, OH
| Date | October 16, 2016 |
| Location | Oregonia, OH |
| Aircraft | MAKELA RV-4 (amateur-built) |
| Purpose of flight | Personal |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Maneuvering-low-alt flying Collision with terr/obj (non-CFIT) |
| Pilot age | 36 |
| Pilot total time | 750 hrs · Building experience |
| Time in type | 200 hrs |
| Fatalities | 2 |
Probable cause
NTSB findings
- Personnel issues-Action/decision-Info processing/decision-Decision making/judgment-Pilot - C
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Altitude-Not attained/maintained - C
- Environmental issues-Physical environment-Object/animal/substance-Wire-Awareness of condition - C
- Environmental issues-Physical environment-Object/animal/substance-Wire-Effect on operation - C
- Environmental issues-Physical environment-Object/animal/substance-Wire-Ability to respond/compensate - C
- Personnel issues-Physical-Health/Fitness-Use of medication/drugs-Pilot
- Personnel issues-Physical-Health/Fitness-Use of alcohol-Pilot
What happened
The private pilot and passenger in the experimental, amateur-built airplane were seen flying at low altitude by several witnesses in various locations before the accident. The witnesses reported the engine was operating before the airplane descended into trees. Postaccident examination of the airplane, wreckage path, and a nearby zipline revealed damage consistent with the outboard section of the right wing having contacted the 1/2-inch galvanized zipline cable. There were no mechanical malfunctions or anomalies with the airplane or engine.
The cable ran between wooden platforms on the east and west sides of a river about 170 ft above ground level. The location of the platforms in wooded areas and the fact that the cable was unmarked likely made the zipline difficult to see. Witness statements and the accident scenario indicate the pilot operated the airplane at extremely low altitudes throughout the flight.
Toxicological testing of the pilot was positive for ethanol and tetrahydrocannabinol (THC, the primary psychoactive substance in marijuana). The blood level of ethanol was below the regulatory limit; however, pilots may be impaired below this threshold. The finding of THC indicated that the pilot had used marijuana sometime before the accident; however, since there is no accepted relationship between blood levels and degree of impairment, whether the impairing effects of THC contributed to the accident could not be determined.