Nelson BENSON B-8M accident near Sandwich, Illinois, August 9, 1994
On August 9, 1994 at about 6:45 pm local time, a Nelson BENSON B-8M (gyroplane), an amateur-built aircraft,, registered N26063, was destroyed in an accident near Sandwich, Illinois. It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
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.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 9, 1994 · about 6:45 pm local time
- Place
- Sandwich, Illinois · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Nelson BENSON B-8M BENSON B-8, amateur-built
- Registration
- N26063 · no longer on the register · serial B8M9176
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
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.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Medical certificate: None
- Seat: ctr
The aircraft
- Last inspection: inspection type not recorded
- Maximum gross weight: 500 lb
- Seats: 1
- Landing gear: fixed
- Engine: Mcculloch 4318A (piston); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 020° at 7 knots
- Visibility: 12 statute miles
- Sky: broken clouds at 2,900 ft; not recorded
- Temperature: 68°F (20°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N26063 the same tail number, which may have belonged to a different aircraft at the time
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.