ERA25LA354 · Jonker Sailplanes (PTY) Ltd JS3
Jonker Sailplanes (PTY) Ltd JS3 · Accident on approach
Event
- NTSB case
- ERA25LA354
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- Event fatalities
- Unknown
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Jonker Sailplanes (PTY) Ltd JS3
- Aircraft type
- Jonker Sailplanes (pty) JS3
- Category
- Glider
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N68MF
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 3 years (built 2022)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Miscellaneous/other
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Personnel issues › Action/decision
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot of the turbine powered (jet sustainer) motorglider reported that during descent to the airport, he deployed and operated the jet sustainer for 90 seconds. After turning off the jet sustainer, the pilot forgot to stow it, resulting in increased drag. After entering the traffic pattern, the pilot configured the glider for landing by extending the flaps and landing gear, but the jet sustainer remained extended. The pilot noticed a sink rate in excess of normal, and attempted to resolve the condition by reducing flaps, but inadvertently placed the flaps in the full negative position, which deployed the spoilers and increased the sink rate further. He continued in the airport traffic pattern; however, during the base leg to final leg turn, he realized that impact with a tree line was likely and decided to level the wings to make contact with the trees in a controlled fashion. The glider subsequently impacted the trees resulting in substantial damage to its right wing. The pilot stated that there were no preimpact mechanical malfunctions with the glider.
Probable cause
The pilot’s failure to properly configure the glider for landing, which resulted in an excessive descent rate during approach, and subsequent collision with trees short of the intended landing area.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA25LA354
- Event ID
- 20250919201045
- Case number
- ERA25LA354
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, cause areas. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 55addda638ac695275b13c0819aeb6f38fc8779eb5bfbe055b87a69ad01ebe17; retrieved 2026-09-16T20:21:56.956Z.