- Date
- August 22, 2019, 20:45 UTC
- Place
- Oxford, FL
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N331AVPipistrel Sinus 912
- Defining event
- Landing: Nose over/nose down
- Weather
- Visual (VMC) · Day
- Status
- Completed · report June 16, 2020
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20190822012149I
- Case key
- 100127
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The pilot’s continued use of battery power during a nonpowered flight in a powered-glider, which depleted the battery to a level that was insufficient to power the starter during the engine restart sequence and resulted in a forced landing to a soft field and a subsequent nose-over.
Findings · 4
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
The pilot reported that he was building hours in the powered-glider to prepare for his glider instructor rating examination. He departed the airport with power and climbed to the west to chase thermals. After the powered-glider reached 4,000 ft above ground level (agl), he shut down the engine, left the battery power on, and continued to climb to 4,500 ft agl. After 30 minutes, he attempted to restart the engine, but the starter only cranked the engine briefly, and the propeller travelled one full revolution and then stopped. After another unsuccessful engine start attempt and with the glider too far away to glide back to the airport, the pilot located a field for a forced landing. During the landing roll, the main landing gear wheels dug into the soft field, and the powered-glider nosed over and then came to rest inverted, which resulted in substantial damage to the engine mount truss. Postaccident examination of the powered-glider revealed that the single battery was depleted to a level that was insufficient to power the starter during the engine restart sequence. The pilot reported that there were no preaccident malfunctions or failures with the airframe or engine that would have precluded normal operation.
Factual narrative
The flight instructor reported that he was building hours in the powered glider in preparation for his glider instructor rating examination. He departed the airport with power and climbed to the west to chase thermals. After reaching 4,000 ft. above ground level (agl), he shut down the engine, left battery power on, and continued to climb to 4,500 ft. After 30 minutes, he attempted to restart the engine, but the starter only cranked the engine briefly and the propeller travelled 1 full revolution then stopped. After another unsuccessful engine start attempt, and too far away to glide back to the airport, he located a field for a forced landing. During the landing roll, the main landing gear wheels dug into the soft field and the glider nosed over, coming to rest inverted. A post-accident examination revealed that the single battery was depleted as it powered the avionics during the non-powered flight. Its depleted level was insufficient to power the starter during the engine restart sequence. The powered glider sustained substantial damage to the engine mount truss. The pilot reported that there were no preimpact malfunctions or failures to the airframe or engine that would have precluded normal operation.
Aircraft
- Registration
- N331AV
- Reported as
- Pipistrel Sinus 912 (No Series)
- Category
- Airplane
- Serial number
- 736 SFN 912 LSA
- Built
- 2015
- Engine
- Rotax, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- San Antonio Light Sport Aircraft Inc
- Registered owner
- San Antonio Light Sport Aircraft Inc
- Airworthiness certificate
- Special, Experimental light sport (Special); Standard, Normal
- Flight plan
- Unknown
- Equipment
- Unknown
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 34
- Injuries
- None
- Certificates
- Private, Flight instructor, Commercial
- Airplane ratings
- Multi-engine land, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Without waivers/limitations
- Seat
- Left
- Flight hours
- 2,700 total · 8 in this make and model
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 100° at 7 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 84 °F, dew point 73 °F
- Altimeter
- 30.03 inHg
- Observed at
- KVVG, 5 nm away
Docket · 3
The files NTSB released with the investigation on April 20, 2020, on NTSB’s docket system: statements, records, photos and specialists’ reports. 317 KB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.