# NTSB CHI82DA349: Bensen BM8, N9463A, Zilwauker, MI, September 9, 1982

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: September 9, 1982, 13:00 local (17:00 UTC)
- Place: Zilwauker, MI
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report September 9, 1983
- Report: Approved by Office Director
- NTSB case key (mKey): 73118
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI82DA349
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/73118/pdf
- Page: https://openairdocs.org/ntsb/CHI82DA349

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, cruise - normal
  - engine assembly,bearing - failure,partial (cause)
- Forced landing, landing - flare/touchdown
  - autorotation - not performed, pilot in command
- Dragged wing,rotor,pod,float or tail/skid, landing - flare/touchdown

## Analysis

DURING FLIGHT AT ABOUT 1500 FT AGL, THE AIRCRAFT ENGINE LOST POWER. THE PILOT MADE A STEEP APPROACH TO LAND IN A SMALL FIELD SURROUNDED BY POWER LINES. HE STATED THAT DURING AN EXTREME FLARE TO STOP THE FORWARD FLIGHT, THE MAIN ROTOR BLADES HIT THE GROUND AND THE ROTOR MAST FAILED. AN EXAMINATION OF THE ENGINE REVEALED THAT THE NO. 1 AND NO. 2 PISTONS WERE DAMAGED BY NEEDLE BEARINGS FROM THE NO. 2 WRIST PIN, MCCULLOCK PN GB138X.

## Aircraft

- Registration: [N9463A](https://openairdocs.org/deregistered/N9463A-2013-03-20), registration cancelled 2013-03-20, S/N 6776, built 1978 (OpenAirDocs)
- Reported make and model: BENSEN BM8
- Registry model: [Porlas-Ralph BENSEN](https://openairdocs.org/model/porlas-ralph-bensen) (registry code 1300126) (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: 6776
- Airframe hours: 63
- Engines: MCCULLOCK 4318AX reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Ralph R. Porlaf
- Registered owner: Ralph R. Porlaf
- Departed: 11, ZILWAUKER, MI
- Destination: 11, ZILWAUKER, MI
- Airport: 11, Browne

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 51; private, commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; flight hours: 243 total, 63 in this make and model, 177 as pilot in command, 3 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 12 knots
- Visibility: 7 statute miles
- Temperature: 167 °F
- Altimeter: 30.00 inHg

## 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 19820909045479A](https://openairdocs.org/incident/19820909045479A), Sep 9, 1982: Amtrbx BENSEN8M, Zilwaukee, MI, Destroyed. Gyrocopter crashed during emergency landing after engine failure.

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.