# NTSB MKC89FA109: Bensen B-8KSB, N37511, Eldon, MO, May 13, 1989

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Field investigation · Final report
- Date: May 13, 1989, 17:15 local (23:15 UTC)
- Place: Eldon, MO
- Coordinates: 38.350856, -92.569145 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.3509&lon=-92.5691&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report July 11, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 34683
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC89FA109
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/34683/pdf
- Page: https://openairdocs.org/ntsb/MKC89FA109

## Probable cause

PILOT'S FAILURE TO MAINTAIN AIRCRAFT CONTROL WHICH RESULTED IN COLLISION WITH THE TERRAIN DURING TAKE OFF.

## Sequence of events

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

- Loss of control - on ground/water, takeoff - roll/run
  - running takeoff - attempted, pilot in command
  - qualification, unqualified person
  - aircraft control - not maintained, pilot in command (cause)
- On ground/water encounter with terrain/water, takeoff - roll/run

## Analysis

THE PILOT LOST CONTROL OF THE GYROCOPTER DURING THE ATTEMPTED TAKEOFF. THE ROTOR SYSTEM, RUDDER ASSEMBLY, AND PROPELLER MADE CONTACT WITH THE TERRAIN. THE PILOT HELD NO AIRMEN OF MEDICAL CERTIFICATES. FAA RECORDS IN OKLAHOMA CITY, OKLAHOMA, REFLECT THAT THE GYROCOPTER WAS SOLD IN 1980 WITH NO SUBSEQUENT REGISTRATION.

## Aircraft

- Registration: [N37511](https://openairdocs.org/deregistered/N37511-2012-09-20), registration cancelled 2012-09-20, S/N SB001, built 1975 (OpenAirDocs)
- Reported make and model: BENSEN B-8KSB
- Registry model: [Switzer BENSEN B-8KSB](https://openairdocs.org/model/switzer-bensen-b-8ksb) (registry code 1300109) (OpenAirDocs)
- Registry engine: [Mcculloch 4318A&E/0-100](https://openairdocs.org/engine/mcculloch-4318a-e-0-100) (registry code 43101, reciprocating) (OpenAirDocs)
- Category: Gyroplane, amateur-built
- Serial number: SB001
- Engines: MCCULLOCH 4318E 72 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Mcgrew, Joseph
- Registered owner: Mcgrew, Joseph T
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, April 15, 1989, 1 hours before
- Departed: ELDON, MO

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; seat: front; flight hours: 135 total, 100 in this make and model, 120 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 320° at 5 knots
- Visibility: 20 statute miles
- Lowest ceiling: 25,000 ft broken
- Temperature: 75 °F, dew point 52 °F
- Altimeter: 29.00 inHg
- Observed at: JEF, 36 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19890513053029A](https://openairdocs.org/incident/19890513053029A), May 13, 1989: Amtrbx BENSENB8*, Eldon, MO, Substantial damage. Lost control on takeoff. Rotors hit prop . No medical or rating.

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.

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