# NTSB CHI89FA150: Prospector FK-1, N4XK, Chilton, WI, July 29, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Field investigation · Final report
- Date: July 29, 1989, 10:30 local (15:30 UTC)
- Place: Chilton, WI
- Location: 44.0302° N, 88.1617° W: Placed by OpenAirDocs: center of Chilton, WI, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=44.0302&lon=-88.1617&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report August 22, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 14264
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI89FA150
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14264/pdf
- Page: https://openairdocs.org/ntsb/CHI89FA150

## Probable cause

THE PILOT'S POOR IN FLIGHT PLANNING IN THAT HE DIVERTED HIS ATTENTION AND CONTINUED THE FLIGHT BEYOND THE ORIGINAL PERIOD PLANNED. BEFORE TAKEOFF THE PILOT WAS AWARE OF HIS FUEL ENDURANCE.

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, cruise - normal
  - fluid,fuel - exhaustion (cause)
  - preflight planning/preparation - inadequate, pilot in command (cause)
  - diverted attention, pilot in command
  - in-flight planning/decision - inadequate, pilot in command (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - soft (contributing factor)
- Nose over, landing - roll

## Aircraft

- Registration: [N4XK](https://openairdocs.org/aircraft/N4XK), registered now, S/N 001, built 1989 (OpenAirDocs)
- Reported make and model: PROSPECTOR FK-1
- Registry model: [Keller Frederick H FK 1 STOL](https://openairdocs.org/model/keller-frederick-h-fk-1-stol) (registry code 05612VE) (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: 001
- Airframe hours: 44
- Engines: LYCOMING O-320 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Frederick H. Keller
- Registered owner: Keller, Frederick
- Airworthiness certificate: Special, Experimental (Special)
- Departed: OSH, OSHKOSH, WI
- Destination: OSH, OSHKOSH, WI

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 1,600 total, 44 in this make and model, 45 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 120° at 6 knots
- Visibility: 15 statute miles
- Lowest ceiling: 20,000 ft broken
- Temperature: 68 °F, dew point 55 °F
- Altimeter: 30.00 inHg
- Observed at: OSH, 15 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 19890729025729A](https://openairdocs.org/incident/19890729025729A), Jul 29, 1989: Amtreb PROSPECTOR, Chilton, WI, Substantial damage. Ran out of fuel on a eaa photo mission. Landed in a soft field and nosed over.

## Other investigations on N4XK (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 WPR10LA155](https://openairdocs.org/ntsb/WPR10LA155), Feb 26, 2010: Keller FK1 Stol (N4XK), Dixie, ID, substantial damage. Probable cause: The failure of the experimental FK1 pilot to maintain clearance from a parked airplane while landing.

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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