# NTSB DEN84FTE04: Homebuilt KR 2, N45757, Boulder, CO, September 18, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: September 18, 1984, 09:30 local (15:30 UTC)
- Place: Boulder, CO
- Coordinates: 40.040355, -105.369888 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.0404&lon=-105.3699&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16251
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN84FTE04
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16251/pdf
- Page: https://openairdocs.org/ntsb/DEN84FTE04

## Sequence of events

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

- Loss of control - on ground/water, landing - roll
  - propeller system/accessories - improper (cause)
  - proper climb rate - not possible, pilot in command (cause)
  - precautionary landing - performed, pilot in command (contributing factor)
  - brakes(normal) - improper, pilot in command (cause)
  - directional control - not maintained, pilot in command
- On ground/water collision with object, landing - roll
  - object - fence

## Analysis

PLT INSTALLED A DIFFERENT PROPELLER ON ACFT TO INCREASE RPM AND THRUST. AFTER TAKEOFF PLT WAS UNABLE TO GAIN SUFFICIENT ALT TO CLR TREES ON BASE LEG. PRECAUTIONARY LANDING WAS MADE ON A HIGHWAY. PLT APPLIED RIGHT BRAKE DURING LANDING ROLL AND ACFT TRAVELED TO THE RIGHT DOWN AN 8 FOOT EMBANKMENT AND THROUGH A BARBED WIRE FENCE.

## Aircraft

- Registration: N45757 (not matched to a registry record)
- Reported make and model: HOMEBUILT KR 2
- Category: Airplane, amateur-built
- Serial number: 007348951
- Engines: VOLKSWAGEN 1834CC 70 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: Stephan (Nmn) Ernst
- Airworthiness certificate: Special, Experimental (Special)
- Departed: 1V5, BOULDER, CO
- Airport: Boulder Muni

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 28; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: front; flight hours: 93 total, 7 in this make and model

## Weather

- Conditions: Visual (VMC), Dawn
- Wind: calm
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 75 °F
- Altimeter: 30.00 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 19840918049719A](https://openairdocs.org/incident/19840918049719A), Sep 18, 1984: Amtr KR2, Boulder, CO, Destroyed. Pilot was testing new prop that he had just installed. Prop would not produce sufficient thrust.

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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