# NTSB DEN00LA091: Cessna 172XP, N758SZ, Larkspur, CO, May 19, 2000 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: May 19, 2000, 09:55 local (15:55 UTC) - Place: Larkspur, CO - Coordinates: 39.180358, -104.890335 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.1804&lon=-104.8903&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report May 8, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 49231 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN00LA091 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/49231/pdf - Page: https://openairdocs.org/ntsb/DEN00LA091 ## Probable cause A forced landing on soft unsuitable terrain. Factors were improper wiring of the electric fuel boost pump, which produce high pressure when either on position was selected causing the engine to flood during the practice engine out approach. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power, go-around (vfr) - fuel system,electric boost pump - other (contributing factor) - electrical system,electric wiring - improper (contributing factor) - maintenance,installation - improper, unknown (contributing factor) - Forced landing, emergency descent/landing - On ground/water encounter with terrain/water, landing - roll - terrain condition - open field - terrain condition - soft (cause) - terrain condition - none suitable (cause) ## Analysis During a dual instructional flight, the flight instructor gave the student a practice engine out approach by reducing power to 'just above idle.' At the completion of the maneuver, the student added power and the engine failed to respond. The instructor took control and conducted a forced landing to the field the student was using as a target for his maneuver. The terrain was soft and the aircraft nosed over during landing roll. Examination of the aircraft/engine, provided evidence the boost pump was improperly wired giving high boost when either high or low was selected. The switch was found on the low selection as prescribed for the maneuver being conducted. When and who made the wiring change was not determined. ## Factual narrative On May 19, 2000, at 0955 mountain daylight time, a Cessna 172XP, N758SZ, sustained substantial damage during a forced landing near Kelly Air Park (U38), Larkspur, Colorado, when it nosed over on landing roll. The certified flight instructor and student pilot were not injured and no flight plan was filed for this instructional flight operating under Title 14 CFR Part 91. The flight departed Centennial Airport, Englewood, Colorado, at 0900. Visual meteorological conditions prevailed. According to the flight instructor, he reduced power to "just above" idle approximately 2,000 feet above ground level (agl) and was having his student practice an engine out approach. The student set up for approach to an open field and the flight instructor said he checked the engine once during the glide, which was described as being in excess of 2 miles. When the student added power at the termination of the approach, the engine failed to respond. The instructor said he took control of the aircraft and decided to land in the field the student had picked during practice. The field was soft and muddy and during landing roll, the nose landing gear dug in and the aircraft nosed over causing substantial damage to the wings, fuselage, and empennage. Examination of the aircraft/engine provided no evidence of an airframe or engine abnormality. It did provide evidence that the fuel boost pump had been improperly wired so that it operated in high if either the "low" or "high" on position was selected. When the wiring was done was not established, and the mixture setting being used by the pilot was also not established. The boost pump switch was found in the "low" position as prescribed for the maneuver being conducted. The closest weather reporting station, approximately 10 miles from the accident site, recorded a temperature of 82 degrees Fahrenheit and a dew point of 55 degrees Fahrenheit during the time period when the accident took place. ## Aircraft - Registration: [N758SZ](https://openairdocs.org/deregistered/N758SZ-2017-02-22), registration cancelled 2017-02-22, S/N R1723336, built 1980 (OpenAirDocs) - Reported make and model: Cessna 172XP - Registry model: [Cessna R172K](https://openairdocs.org/model/cessna-r172k) (registry code 2072431) (OpenAirDocs) - Registry engine: [Continental IO-360 series](https://openairdocs.org/engine/continental-io-360-series) (registry code 17025, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1723336 - Airframe hours: 3423 - Engines: Continental IO360KB4B 210 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Operator: Dan Bailey - Registered owner: Rwh Entprises - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, April 6, 2000 - Departed: APA, ENGLEWOOD, CO - Destination: 38U, CO ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 30; flight instructor, commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 569 total, 35 in this make and model, 514 as pilot in command, 265 in the last 90 days, 84 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 8 knots - Visibility: 15 statute miles - Lowest ceiling: 20,000 ft broken - Temperature: 54 °F, dew point 43 °F - Altimeter: 30.00 inHg - Observed at: AFF, 10 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 20000519010519A](https://openairdocs.org/incident/20000519010519A), May 19, 2000: Cessna R172K, Elbert, CO, No damage. (-23) On may 19, 2000 at 09:40 MDT, a Cessna 172XP, N758SZ, sustained substantial damage during an emergency landing near kelly air park (CO15), larkspur, CO.,… 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.