# NTSB CHI97LA170: Waco YMF, N820MM, Longville, MN, June 14, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: June 14, 1997, 13:20 local (18:20 UTC) - Place: Longville, MN - Coordinates: 46.979011, -94.210914 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.9790&lon=-94.2109&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report January 30, 1998 - Report: Approved by Office Director - NTSB case key (mKey): 10597 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI97LA170 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/10597/pdf - Page: https://openairdocs.org/ntsb/CHI97LA170 ## Probable cause failure of the pilot to maintain directional control of the airplane. Factors relating to the accident were: the gusty wind condition and the ditch. ## 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 - weather condition - gusts (contributing factor) - directional control - not maintained, pilot in command (cause) - Nose over, landing - roll - terrain condition - ditch (contributing factor) ## Analysis The pilot landed the airplane on runway 13. The airplane weathervaned to the right, and the pilot allowed it to exit the runway. In the area off the runway, the airplane impacted a ditch and nosed over. The pilot said he elected to land the airplane on runway 13 due to the indication of the windsock. He said that eyewitnesses approached him after the accident and said the windsock did not indicate the actual wind condition; they told him that the wind was from the northwest at 15 knots. About 5 minutes before the accident, a weather station (36 nautical miles southwest of the accident site) was reporting winds of 230 degrees at 6 knots with gusts to 16 knots. The same station recorded winds of 170 at 3 knots, 15 minutes after the accident. ## Factual narrative On June 14, 1997, at 1320 central daylight time, a Waco YMF, N820MM, exited runway 13 (3,781' x 75' dry/asphalt) at Longville Municipal Airport, near Longville, Minnesota. The airplane sustained substantial damage when it nosed over in a ditch. The pilot and one passenger reported no injuries. The personal 14 CFR Part 91 flight was operating in visual meteorological conditions. No flight plan was on file. The flight departed Minneapolis, Minnesota, at 1150. The pilot stated that he conducted a landing on runway 13 due to the indication of the windsock showing the prevailing wind from 180 degrees. He said on landing that the airplane "weathervaned" to the right and he allowed it to depart the runway to avoid a ground loop. There is a ditch running parallel to the runway about 50 feet off the runway. The airplane impacted the ditch and nosed over. The pilot said that witnesses to the accident told him the windsock was not recording the actual wind which they said was from the northwest at 15 knots. A weather reporting station located 36 nautical miles to the southwest of the accident site was reporting winds of 230 degrees at 6 knots gusting to 16 knots 5 minutes prior to the accident and the same reporting station recorded winds of 170 degrees at 3 knots 15 minutes after the accident. An onsite inspection of the windsock after the accident by a Federal Aviation Administration inspector revealed that the windsock turned freely, but did not always record the wind accurately. He attributed this to the location of the wind sock in the proximity of buildings. ## Aircraft - Registration: [N820MM](https://openairdocs.org/deregistered/N820MM-2007-10-26), registration cancelled 2007-10-26, S/N F5C-056, built 1993 (OpenAirDocs) - Reported make and model: Waco YMF - Registry model: [Classic WACO YMF](https://openairdocs.org/model/classic-waco-ymf) (registry code 2240101) (OpenAirDocs) - Registry engine: [Jacobs R755B series](https://openairdocs.org/engine/jacobs-r755b-series) (registry code 35007, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: F5C-056 - Airframe hours: 550 - Engines: Jacobs R-755-B2M 275 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Md Aero, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 15, 1997, 18 hours before - Departed: MIC, MINNEAPOLIS, MN - Destination: D33 - Airport: D33, Longville Municipal, runway 13, 3,781 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: rear; flight hours: 1,123 total, 196 in this make and model, 1,123 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 45 °F - Altimeter: 29.00 inHg - Observed at: KPK, 36 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 19970614019949A](https://openairdocs.org/incident/19970614019949A), Jun 14, 1997: Waco YMF, Longville, MN, Substantial damage. Landed downwind overran end into a ditch. Flipped over. Windsock blocked by trees. Ditch not in airport diagrams. (-23) the Longville airport windsock is… ## Other investigations on N820MM (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 MIA99LA117](https://openairdocs.org/ntsb/MIA99LA117), Apr 2, 1999: Waco YMF-5 (N820MM), Boca Raton, FL, substantial damage. Probable cause: The pilot's failure to select a suitable forced landing site following a partial loss of engine power due to failed cylinder holdddown studs, and the subsequent collision with trees. A factor in the… 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.