# NTSB DEN04LA108: Davis-Zenair Stol CH 801, N10627, Erie, CO, July 21, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 21, 2004, 11:30 local (17:30 UTC) - Place: Erie, CO - Coordinates: 40.020576, -105.039916 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.0206&lon=-105.0399&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 3, 2004 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 59730 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN04LA108 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/59730/pdf - Page: https://openairdocs.org/ntsb/DEN04LA108 ## Probable cause impact with terrain during a forced landing following a loss of engine power for underdetermined reasons. A contributing factor was the lack of suitable terrain for a forced landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - nonmechanical, approach - vfr pattern - downwind - cooling system - malfunction (cause) - fluid,coolant - overtemperature (cause) - reason for occurrence undetermined - Forced landing, emergency descent/landing - In flight collision with terrain/water, emergency descent/landing - terrain condition - open field (contributing factor) - terrain condition - plowed/furrowed (contributing factor) ## Analysis According to the pilot, the airplane's 1988 liquid-cooled Mazda Twin-rotor automotive engine had accumulated approximately 2,500 road miles, but the airplane had accumulated a total of only 1.5 hours of flight time. The pilot said he was conducting the initial test flight and had completed 10 takeoffs and landings on runway 33. While on crosswind following the 11th takeoff, he noticed that the indicated engine coolant temperature had increased from, a normal operating temperature of 110 degrees F., to 220 degrees F. The increase in temperature was followed by a drop in engine rpm and a partial loss of engine power. Unable to maintain pattern altitude, the pilot attempted to land on runway 09, but the pilot was forced to land in a plowed field approximately 200 feet short of the runway. The impact displaced the left wing aft, collapsed the nose landing gear assembly, and buckled the firewall. An examination of the airplane revealed no anomalies. ## Factual narrative On July 21 2004, at approximately 1130 mountain daylight time, a Davis-Zenair, STOL CH 801, N10627, was substantially damaged following a loss of engine power, when it impacted terrain during a forced landing on a field near Erie, Colorado. The airline transport certificated pilot was not injured. Visual meteorological conditions prevailed at the time of the accident. The local test flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The flight originated at Erie-Tri-County Airport (48V), Erie, Colorado, at approximately 1000. According to the pilot, the airplane's 1988 liquid-cooled Mazda Twin-rotor automotive engine had accumulated approximately 2,500 road miles, but the airplane had accumulated a total of only 1.5 hours of flight time. The pilot said he was conducting the initial test flight and had completed 10 takeoffs and landings on runway 33. While on crosswind following the 11th takeoff, he noticed that the indicated engine coolant temperature had increased from, a normal operating temperature of 110 degrees F., to 220 degrees F. The increase in temperature was followed by a drop in engine rpm and a partial loss of engine power. Unable to maintain pattern altitude, the pilot attempted to land on runway 09, but the pilot was forced to land in a plowed field approximately 200 feet short of the runway. The impact displaced the left wing aft, collapsed the nose landing gear assembly, and buckled the firewall. An examination of the airplane revealed no anomalies. ## Aircraft - Registration: [N10627](https://openairdocs.org/deregistered/N10627-2012-12-13), registration cancelled 2012-12-13, S/N 84292, built 2004 (OpenAirDocs) - Reported make and model: Davis-Zenair STOL CH 801 - Registry model: [Davis Guy STOL CH 801](https://openairdocs.org/model/davis-guy-stol-ch-801) (registry code 056110V) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 84292 - Airframe hours: 1.5 - Engines: Mazda Twin Rotor 196 horsepower reciprocating - Damage: Substantial damage - Flight: Flight test, Part 91 - Registered owner: Guy Davis - Airworthiness certificate: Special, Experimental (Special) - Departed: 48V, Erie, CO - Destination: 48V, Erie, CO - Airport: 48V, Erie-Tri-County ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; last flight review July 28, 2004; seat: left; flight hours: 7,271 total, 2 in this make and model, 6,617 as pilot in command, 26 in the last 90 days, 16 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 0° at 5 knots - Visibility: 80 statute miles - Lowest ceiling: none - Temperature: 86 °F, dew point 46 °F - Altimeter: 30.15 inHg - Observed at: KBJC, 7 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 20040721031379A](https://openairdocs.org/incident/20040721031379A), Jul 21, 2004: Amtr STOLCH801, Erie, CO, Substantial damage. (-23) The pilot was conducting an initial test flight and had completed ten take-offs and landings on runway 33. Just after turning downwind from crosswind… 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. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.