Fuel Exhaustion & Starvation · NTSB ERA19FA256
MORIARTY MARVIN AVENTURA II — Minneola, FL
| Date | August 23, 2019 |
| Location | Minneola, FL |
| Aircraft | MORIARTY MARVIN AVENTURA II (amateur-built) |
| Purpose of flight | Personal |
| Conditions | Day · Visual Meteorological Cond |
| Phase / occurrence | Uncontrolled descent Collision with terr/obj (non-CFIT) |
| Pilot age | 63 |
| Pilot total time | 379 hrs · Building experience |
| Time in type | 71 hrs |
| Fatalities | 1 |
Probable cause
NTSB findings
- Personnel issues-Task performance-Use of equip/info-Aircraft control-Pilot
- Aircraft-Aircraft oper/perf/capability-Performance/control parameters-Angle of attack-Capability exceeded
- Personnel issues-Task performance-Maintenance-Modification/alteration-Pilot
- Aircraft-Aircraft power plant-Engine fuel and control-Fuel control/carburetor-Incorrect service/maintenance
What happened
According to the pilot's son, he and his father were working on the experimental, amateur-built airplane's carburetor the day before the accident to improve the fuel consumption. They replaced the carburetor jets with smaller ones, but that change made the engine run roughly. On the morning of the accident, the pilot told his son that he fixed the airplane by adjusting the carburetor float tabs, allowing more fuel to enter the carburetor bowl. They then performed an engine run-up, and it ran normally. The pilot’s son stated that, during takeoff, the airplane was not climbing like it had in the past. When the airplane reached about 300 ft above ground level, the engine started to sputter and run roughly. He stated that it looked like his father tried to turn the airplane back to the runway and made a sharp left turn but that shortly after the turn, the airplane descended straight down to the ground.
Postaccident examination of the engine found that the choke on the carburetors was safety wired in the open position. The top spark plugs were removed and noted to be black and sooty, consistent with the engine running with an excessively rich fuel ratio. No other mechanical anomalies were noted with the engine that would have precluded normal operation. Given the available information, it is likely that the pilot’s modifications to the airplane’s engine resulted in it running excessively rich, which resulted in the partial loss of power and engine roughness that occurred during the takeoff. Additionally, the pilot exceeded the airplane’s critical angle of attack while attempting to return to the airport, which led to an aerodynamic stall and impact with terrain.
Toxicological testing revealed Delta-9-THC (tetrahydrocannabinol, the active compound in marijuana) in the pilot’s blood and liver specimens; however, it could not be determined if the pilot's marijuana use impacted his behavior or decision making before or during the accident flight.