CHI94LA274 · Nelson BENSON B-8M BENSON B-8
Nelson BENSON B-8M BENSON B-8 · Accident: loss of control in flight en route
Event
- NTSB case
- CHI94LA274
- 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
- API-reported fatalities
- 1 · all aircraft and ground
- Ground fatalities
- 0
- 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
Nelson BENSON B-8M BENSON B-8
- Aircraft type
- Nelson BENSON B-8M
- Category
- Gyroplane
- 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
- N26063
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- Not recorded
- 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
- En route · climb to cruise
- First occurrenceThe 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
- Loss of control in flight
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Owner/pilot mechanic › Maintenance, modification, improper
- Pilot in command › Aircraft control, not maintained
- Pilot in command › Planning/decision, improper
- Rotorcraft flight control system › Inadequate
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
SEVERAL WITNESSES TO THE ACCIDENT REPORTED THAT THE GYROPLANE APPEARED UNSTABLE AS IT CLIMBED TO A MAXIMUM ALTITUDE OF APPROXIMATELY 50 FEET. TWO WITNESSES DESCRIBED THE GYROPLANE 'TIPPING' AND 'DIPPING' SHORTLY AFTER TAKEOFF. THEY SAID THE ENGINE SOUNDED AS THOUGH IT WAS RUNNING AT FULL POWER IMMEDIATELY PRIOR TO THE ACCIDENT. THE GYROPLANE PITCHED DOWN IN A MANNER DESCRIBED BY ONE WITNESS AS A 'SOMERSAULT' AND IMPACTED THE TERRAIN IN AN INVERTED, NEAR VERTICAL, NOSE DOWN ATTITUDE. AN UNTESTED/CUSTOM ROTOR HEAD WAS REPORTED TO HAVE BEEN INSTALLED ON THE GYROPLANE. ACCORDING TO THE PILOT'S WIFE, HE HAD MODIFIED THE GYROPLANE AFTER HAVING A PREVIOUS ACCIDENT; SHE DID NOT BELIEVE THE GYROPLANE HAD BEEN SUCCESSFULLY FLOWN SINCE IT WAS MODIFIED. TWO PERSONS, WHO WERE FAMILIAR WITH THE GYROPLANE, INDICATED THAT THE MODIFICATION WOULD HAVE AFFECTED CONTROLLABILITY OF THE AIRCRAFT. NO RECORD WAS FOUND THAT THE PILOT HAD EVER BEEN ISSUED A PILOT CERTIFICATE. TOXICOLOGY TESTS REVEALED TRACES OF METABOLITES OF COCAINE, SUGGESTING USE IN THE PAST THAT HAD BECOME METABOLIZED BEFORE FLIGHT.
Probable cause
IMPROPER PLANNING/DECISION BY THE PILOT (OWNER/PILOT/MECHANIC), AND HIS IMPROPER MODIFICATION OF THE FLIGHT CONTROL SYSTEM, WHICH RESULTED IN HIS FAILURE (OR INABILITY) TO MAINTAIN CONTROL OF THE GYROCOPTER. A FACTOR RELATED TO THE ACCIDENT WAS: THE PILOT'S LACK OF FLIGHT TRAINING.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI94LA274
- Event ID
- 20001206X01999
- Case number
- CHI94LA274
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
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. 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: e433544aaf458d3d0be16f5516b68662283314df5a006166363e40f2295dc92a; retrieved 2026-09-21T00:03:11.937Z.