# NTSB CHI91DEE06: Robinson R22B, N91MG, Mineral, IL, June 5, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: June 5, 1991, 11:00 local (16:00 UTC)
- Place: Mineral, IL
- Coordinates: 41.379875, -89.829238 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.3799&lon=-89.8292&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 14825
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91DEE06
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14825/pdf
- Page: https://openairdocs.org/ntsb/CHI91DEE06

## Probable cause

FAILURE OF THE PILOT TO MAINTAIN CLEARANCE FROM THE POWER LINE.

## Sequence of events

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

- In flight collision with object, maneuvering - aerial application
  - object - wire,transmission
  - clearance - not maintained, pilot in command (cause)
- Forced landing, descent - emergency
- Hard landing, landing

## Analysis

A COMMERICAL PILOT APPLYING CHEMICAL SPRAY TO A CORN FIELD REVERSED COURSE FOR A DOWNWIND PASS.  A POWER LINE BORDERED THE NEAR END OF THE FIELD AND THE PILOT ATTEMPTED TO DROP JUST OVER THE LINE TO COMMENCE THE RUN.  THE TAIL ROTOR STRUCK THE POWER LINE,  SHEARING BOTH TAIL ROTOR BLADES CLOSE TO THE HUB.  THE PILOT REDUCED POWER AND CONTINUED THE DESCENT TO A HARD LANDING WITH NO TORQUE CONTROL.

## Aircraft

- Registration: [N91MG](https://openairdocs.org/deregistered/N91MG-2005-03-22), registration cancelled 2005-03-22, S/N 1725, built 1991 (OpenAirDocs)
- Reported make and model: ROBINSON R22B
- Registry model: [Robinson Helicopter R22 BETA](https://openairdocs.org/model/robinson-helicopter-r22-beta) (registry code 7640110) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1725
- Engines: LYCOMING O-320 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Darrell L. Marquis
- Registered owner: Marquis Grain Inc.
- Airworthiness certificate: Special, Restricted (Special)
- Departed: NONE, BUDA, IL

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 35; flight instructor, commercial; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 618 total, 480 in this make and model, 510 as pilot in command, 80 in the last 90 days, 55 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 80° at 10 knots, gusting 12
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 81 °F, dew point 70 °F
- Altimeter: 29.00 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 19910605020369A](https://openairdocs.org/incident/19910605020369A), Jun 5, 1991: Robsin R22BETA, Mineral, IL, Substantial damage. Settling with power occurred over powerline. Tail rotor sheared on powerline. Cut power to stop spin. Hard impact

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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