Probable cause
Failure of the engine/propeller drive belt.
NTSB analysis
The pilot of the experimental amateur-built airplane stated that he was on final approach when the airplane “abruptly” turned right 45°, and the flight controls no longer felt normal. The pilot said it was a challenge to maneuver the airplane and, as he attempted to avoid trees, the airplane stalled and impacted the ground. A postaccident examination of the airplane and its two-stroke engine revealed that the belt that connected the engine output sprocket to the propeller drive sprocket had broken. The belt had not been manufactured for use in aircraft. Examination of the edges of the belt revealed that it appeared rubbed with exposed core strands in several areas consistent with lateral travel or tracking and that the belt ultimately broke due to tensile overload failure.
Text from the NTSB. Open the NTSB docket for ERA21LA109 for the full record.
Event
- Date
- Jan 21, 2021
- Type
- Accident
- Place
- Minneola, Florida
- Highest injury
- Serious
- Serious injuries
- 1
- Weather
- Visual (VMC)
- Light
- Day
Amateur-built Challenger II
- N-number
- N4469Z
- Category
- Airplane
- Year built
- 2008
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Personal
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.