# NTSB LAX84LA072: Bensen B8M, Rocklin, CA, November 25, 1983

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: November 25, 1983, 09:30 local (17:30 UTC)
- Place: Rocklin, CA
- Coordinates: 38.799022, -121.239219 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.7990&lon=-121.2392&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24093
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX84LA072
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24093/pdf
- Page: https://openairdocs.org/ntsb/LAX84LA072

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of engine power(total) - nonmechanical, cruise
  - planning/decision - improper, pilot in command (cause)
  - weather condition - carburetor icing conditions (contributing factor)
  - carburetor heat - not possible
  - fuel system,carburetor - ice (cause)
- Forced landing, landing
- In flight collision with terrain/water, landing

## Analysis

THE PLT WAS OPERATING HIS HOME BUILT, NON-REGISTERED GYROCOPTER AS AN ULTRALIGHT VEHICLE. REPORTEDLY, THE ENG LOST POWER DURING FLT, AND SUBSEQUENTLY, THE GYROCOPTER WAS DAMAGED DURING A FORCED LANDING. ACCORDING TO THE PLT, HE ENCOUNTERED CARBURETOR ICING WHICH RESULTED IN THE LOSS OF POWER. THE ENG WAS NOT EQUIPPED WITH A CARBURETOR HEAT SYS. ALSO, THE TEMP & DEW POINT WERE 49 & 41 DEG, RESPECTIVELY. ACCORDING TO ICING PROBABILITY CHARTS, A FLOAT TYPE CARBURETOR COULD ENCOUNTER SERIOUS CARBURETOR ICING CONDITIONS AT THOSE TEMPS.

## Aircraft

- Registration: UNREG (not matched to a registry record)
- Reported make and model: BENSEN B8M
- Category: Gyroplane, amateur-built
- Serial number: JH-2
- Airframe hours: 2
- Engines: MCCULLOCH UNKNOWN 72 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: John T. Hall
- Registered owner: None
- Departed: LINCOLN, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; airplane ratings: single-engine land; medical: unknown, expired; seat: center; flight hours: 110 total, 102 in this make and model, 102 as pilot in command, 2 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 350° at 4 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 48 °F, dew point 41 °F
- Altimeter: 30.00 inHg
- Observed at: SAC, 19 nm away

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.