# NTSB CHI82DA347: Bell 47G-4A, N4090G, Near Brooten, MN, August 20, 1982

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: August 20, 1982, 09:00 local (14:00 UTC)
- Place: Near Brooten, MN
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report August 20, 1983
- Report: Approved by Office Director
- NTSB case key (mKey): 71852
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI82DA347
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/71852/pdf
- Page: https://openairdocs.org/ntsb/CHI82DA347

## Sequence of events

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

- Loss of engine power, takeoff - initial climb
  - reason for occurrence undetermined (cause)
  - ignition system,spark plug - worn
- Forced landing, landing - flare/touchdown
  - autorotation - performed, pilot in command
- Hard landing, landing - flare/touchdown
- Other gear collapsed, landing - flare/touchdown
  - landing gear - overload

## Analysis

THE PILOT HAD BEEN ENGAGED IN A SPRAYING OPERATION FOR 2.5 HRS WHEN HE RETURNED AND LANDED ON A FLAT BED TYPE TRAILER TO SERVICE THE HELICOPTER. AFTER THE HOPPER WAS SERVICED WITH 60 GAL OF HERBICIDE, THE PILOT BEGAN HIS TAKE OFF. HE STATED THAT JUST AFTER LIFT-OFF, THE HELICOPTER LOST POWER AND YAWED TO THE LEFT. HE STATED THAT HE ATTEMPTED TO CUSHION THE LANDING WITH THE COLLECTIVE, BUT THE GEAR COLLAPSED AND THE MAIN ROTOR HIT A FENCE. AN EXAMINATION REVEALED NO DISCREPANCIES OF THE TRANSMISSION OR ENGINE, EXCEPT THE SPARK PLUGS WERE SEVERELY WORN. AN ENGINE RUN-UP WAS MADE AND IT OPERATED SATISFACTORILY.

## Aircraft

- Registration: [N4090G](https://openairdocs.org/deregistered/N4090G-2018-03-05), registration cancelled 2018-03-05, S/N 7640, built 1968 (OpenAirDocs)
- Reported make and model: BELL 47G-4A
- Registry model: [Bell 47G-4A](https://openairdocs.org/model/bell-47g-4a) (registry code 1181031) (OpenAirDocs)
- Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 7640
- Airframe hours: 4300
- Engines: LYCOMING VO-540-B1B3 280 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 137
- Operator: Bonanza Valley Aviation
- Registered owner: Bonanza Valley Aviation
- Departed: NEAR BROOTEN, MN
- Destination: NEAR BROOTEN, MN

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 36; airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; flight hours: 8,460 total, 1,512 in this make and model, 175 in the last 90 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 225° at 5 knots
- Visibility: 15 statute miles
- Temperature: 140 °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 19820820048659A](https://openairdocs.org/incident/19820820048659A), Aug 20, 1982: Bell 47G, Brooten, MN, Substantial damage. Engine quit on vertical liftoff from trailer pad. Rotors struck the ground. Found worn out spark plugs.

## Other investigations on N4090G (1)

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.

- [NTSB MIA69D0404](https://openairdocs.org/ntsb/MIA69D0404), Mar 12, 1969: Bell 47G-4A (N4090G), Fort Pierce, FL, substantial damage

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.