# NTSB MKC82DA166: Scorpion 133, N13420, Mondamin, IA, September 5, 1982

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Final report
- Date: September 5, 1982, 16:30 local (21:30 UTC)
- Place: Mondamin, IA
- Coordinates: 41.70082, -96.020973 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.7008&lon=-96.0210&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report September 5, 1983
- Report: Approved by Office Director
- NTSB case key (mKey): 71746
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC82DA166
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/71746/pdf
- Page: https://openairdocs.org/ntsb/MKC82DA166

## Sequence of events

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

- Loss of control - in flight, landing - flare/touchdown
  - rotorcraft flight control,collective control - incorrect (cause)
  - maintenance,adjustment - improper, other maintenance personnel (contributing factor)
  - condition(s)/step(s) insufficiently defined, production/design personnel (cause)
  - rotor rpm - not maintained, pilot in command
- Hard landing, landing - flare/touchdown

## Analysis

AFTER A GROUND ADJUSTMENT TO THE COLLECTIVE PITCH ON HIS HOMEBUILT HELICOPTER, THE PILOT TOOKOFF TO PRACTICE HOVERING TAKEOFF AND LANDING. IN AN ATTEMPT TO HOVER CLOSE TO GROUND, HE RAISED THE COLLECTIVE AND THE AIRCRAFT SHOT UP ABOUT 30 FEET. IT THEN FELL OFF TO THE LEFT AND IMPACTED THE GROUND A LATER DISCUSSION WITH FACTORY REPRESENTATIVE DISCLOSED A DIFFERENCE BETWEEN VERBAL ADJUSTMENT INSTRUCTIONS AND THOSE ON THE PUBLISHED PLANS FOR BUILDING THE AIRCRAFT.

## Aircraft

- Registration: [N13420](https://openairdocs.org/deregistered/N13420-2013-03-26), registration cancelled 2013-03-26, S/N RW 2958, built 1982 (OpenAirDocs)
- Reported make and model: SCORPION 133
- Registry model: [Deitering Gary SCORPIAN 133](https://openairdocs.org/model/deitering-gary-scorpian-133) (registry code 13025CT) (OpenAirDocs)
- Registry engine: [Rotorway RW-145 series](https://openairdocs.org/engine/rotorway-rw-145-series) (registry code 55005, reciprocating) (OpenAirDocs)
- Category: Helicopter, amateur-built
- Serial number: RW2958
- Airframe hours: 10
- Engines: ROTORWAY RW145 145 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Gary Deitering
- Registered owner: Gary Deitering
- Departed: MONDAMIN, IA
- Destination: MONDAMIN, IA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 35; private; medical: class 3, valid medical--no waivers/lim.; flight hours: 73 total, 11 in this make and model, 41 as pilot in command, 11 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Temperature: 167 °F

## 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 19820905043789A](https://openairdocs.org/incident/19820905043789A), Sep 5, 1982: Amtrrw SCORPION1, Mondamin, IA, Substantial damage. Upon applying collective pitch, aircraft climbed 30 feet then fell off to the left, impacting ground.

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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