Moriarty Marvin AVENTURA II N9143M

Summary

On 23 August 2019 at about 15:15 local time, a Moriarty Marvin AVENTURA II registered N9143M was involved in an accident near Minneola, Florida, United States. One person was on board and one died. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

23 August 2019 at 15:15

Classification

Accident

Location

Minneola, Florida, United States

Nearest airport

Florida Flying Gators (3FD4)

Coordinates

28.6306, -81.8044

Aircraft

Moriarty Marvin AVENTURA II

Registration

N9143M

Category

Airplane

Year built

2001

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Minneola → Deland

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ERA19FA256

1 person died.

The pilot’s improper modifications to the airplane’s engine, which resulted in the partial loss of engine power. Contributing to the outcome was the pilot's exceedance of the airplane’s critical angle of attack during an attempted return to the airport following a partial loss of engine power, which resulted in an aerodynamic stall and impact with terrain.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

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.

Quoted verbatim from the NTSB record.