# NTSB CHI84LA286: Gillmore Moni, N157LG, Joliet, IL, July 7, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 7, 1984, 16:00 local (21:00 UTC)
- Place: Joliet, IL
- Coordinates: 41.519664, -88.11956 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.5197&lon=-88.1196&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 12690
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI84LA286
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/12690/pdf
- Page: https://openairdocs.org/ntsb/CHI84LA286

## 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,hub - fatigue (cause)
  - insufficient standards/requirements,aircraft, manufacturer (contributing factor)
  - propeller system/accessories,hub - separation (cause)
  - remedial action - not possible, pilot in command
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - crop
  - terrain condition - ground

## Analysis

THE PROP SEPARATED FROM THE ACFT AT APRX 500 FT AGL DURING THE INITIAL TAKEOFF CLIMB. A FORCED LANDING WAS MADE IN A CORN FIELD. THE PROP WAS ATTACHED BY MEANS OF 4 5/16 INCH BOLTS AND RETAINING NUTS. TWO OF THE FOUR BOLT PORTIONS REMAINING AFTER THE ACCIDENT WERE REMOVED. ONE OF WHICH WAS TESTED AND PROGRESSIVE FATIGUE WAS FOUND. THE KIT MANUFACTURER LATER ISSUED A SERVICE BULLETIN STATING THAT WITH THE NUTS PROPERLY TORQUED IT IS POSSIBLE FOR THE NUTS TO BOTTOM OUT ON THE BOLT THREADS WHICH WOULD RESULT IN THE BOLTS SHEARING. THE MANUFACTURER SUGGESTS INSTALLING WASHERS AT THE HEAD OF THE BOLT TO PREVENT THE NUT FROM BOTTOMING OUT.

## Aircraft

- Registration: [N157LG](https://openairdocs.org/aircraft/N157LG), registered now, S/N 107 (OpenAirDocs)
- Reported make and model: GILLMORE MONI
- Registry model: [American Blimp A-1-70G](https://openairdocs.org/model/american-blimp-a-1-70g) (registry code 3850112) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 157
- Airframe hours: 30
- Engines: KFM 107E 35 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Gary A. Gillmore
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, September 22, 1983
- Destination: UGN, WAUKEGAN, IL
- Airport: 0C3, Wilhelmi

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; flight hours: 30 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 80° at 8 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 70 °F, dew point 45 °F
- Altimeter: 29.00 inHg
- Observed at: MDW, 23 nm away

## 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 19840707030759A](https://openairdocs.org/incident/19840707030759A), Jul 7, 1984: Amtr MONI, Joliet, IL, Substantial damage. Propeller separated after takeoff. Propeller retaining bolts sheared. Service bulletin put out late to correct.

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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