# NTSB CHI91DEV05: Ullman Vari Viggen, N22VV, Greenville, IL, September 29, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: September 29, 1991, 18:00 local (23:00 UTC)
- Place: Greenville, IL
- Coordinates: 38.880592, -89.400672 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.8806&lon=-89.4007&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report February 8, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 14865
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91DEV05
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14865/pdf
- Page: https://openairdocs.org/ntsb/CHI91DEV05

## Probable cause

IMPROPER MAINTENANCE INSTALLATION OF THE PROPELLER.

## Analysis

AN OWNER BUILT EXPERIMENTAL AIRPLANE EXPERIENCED SEPARATION OF THE WOODEN PROPELLER DURING CLIMB FROM TAKEOFF. EXAMINATION OF THE FAILED ATTACHMENT BOLTS SHOWED THE NUTS HAD BOTTOMED AGAINST THE UNTHREADED SHANK WHILE CLINCHING THE PROPELLER HUB TO ITS FLANGE.

## Sequence of events

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

- Airframe/component/system failure/malfunction, takeoff - initial climb
  - propeller system/accessories,prop blade retention - failure,total
  - maintenance,installation - improper, pilot in command (cause)
  - propeller system/accessories,hub - separation
  - remedial action - initiated, pilot in command
- Forced landing, descent - emergency
- Complete gear collapsed, landing - roll
  - terrain condition - crop
  - landing gear,main gear attachment - overload
  - landing gear - collapsed

## Aircraft

- Registration: [N22VV](https://openairdocs.org/deregistered/N22VV-2016-02-08), registration cancelled 2016-02-08, S/N 204, built 1986 (OpenAirDocs)
- Reported make and model: ULLMAN VARI VIGGEN (VARI VIGGE)
- Registry model: [Ullman Emerald J VARIVIGGEN](https://openairdocs.org/model/ullman-emerald-j-variviggen) (registry code 056098U) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 204
- Airframe hours: 228
- Engines: LYCOMING O-320-E2A 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Emerald J. Ullman
- Registered owner: Emerald J. Ullman
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Unknown, April 2, 1991, 34 hours before
- Destination: 3K4, HILLSBORO, IL
- Airport: GRE, Greenville Municipal, runway 18, 4,000 × 75 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 58; private; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 1,293 total, 220 in this make and model, 1,251 as pilot in command, 22 in the last 90 days, 5 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 5 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 79 °F, dew point 7 °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 19910929043469A](https://openairdocs.org/incident/19910929043469A), Sep 29, 1991: Amtrru VARIVIGGEN, Greenville, IL, Substantial damage. Prop assembly departed aircraft shortly after departure. Landed off airport. All six attach bolts failed. Stripped.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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