# NTSB CHI04LA075: Cessna 120, N73034, Merrill, WI, February 21, 2004 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 21, 2004, 16:55 local (22:55 UTC) - Place: Merrill, WI - Coordinates: 45.199165, -89.716392 - Nearby events: https://openairdocs.org/map.md?lat=45.1992&lon=-89.7164&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report September 1, 2004 - Report: Approved by Office Director - Parties: Federal Aviation Administration - NTSB case key (mKey): 58805 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI04LA075 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/58805/pdf - Page: https://openairdocs.org/ntsb/CHI04LA075 ## Probable cause The pilot's selection of unsuitable terrain to conduct a landing. Factors were the reported flat light conditions and the uneven terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - On ground/water encounter with terrain/water, landing - terrain condition - rough/uneven (contributing factor) - unsuitable terrain or takeoff/landing/taxi area - selected, pilot in command (cause) - terrain condition - water,frozen - light condition - other (contributing factor) - Nose over, landing ## Analysis The ski-equipped airplane sustained substantial damage when it impacted uneven terrain and subsequently nosed over during its landing on a frozen river. The pilot reported that he "had determined incorrectly that this was a very good place to land." The pilot stated that the snow was fresh, smooth, evenly colored, and not tracked up by vehicle traffic. The pilot reported that upon landing, the right ski fell into a snowmobile path that was approximately 18 inches deep. The airplane immediately nosed over. The pilot reported that there was 'flat' light conditions at the time of the accident. ## Factual narrative On February 21, 2004, about 1655 central standard time, a ski-equipped Cessna 120, N73034, operated by a private pilot, sustained substantial damage when it impacted uneven terrain and subsequently nosed over during a landing on the frozen Wisconsin River, near Merrill, Wisconsin. The personal flight was operated under 14 CFR part 91. Visual meteorological conditions prevailed at the time of the accident. The pilot and passenger reported no injuries. The flight originated from the Merrill Municipal Airport (RRL), near Merrill, Wisconsin, about 1600. The pilot reported: The accident occurred when I landed on Lake Alexander, a portion of the Wisconsin River. I had determined incorrectly that this was a very good place to land. The snow was fresh, smooth, evenly colored, and not tracked up by vehicle traffic. Upon landing my [right] ski fell into a snowmobile path that was [approximately] 18 [inches] deep. The rut was at a near 45 [degrees] to my direction. The ski buried and dove stopping suddenly flipping me over. ... The light was 'flat' making surface detail difficult to [perceive]. At 1657, the recorded RRL weather was: Winds 280 degrees at 6 knots; visibility 10 statute miles; sky condition clear; temperature -2 degrees C; dew point -8 degrees C; altimeter 29.94 inches of mercury. The pilot reported no mechanical malfunctions in reference to the flight. ## Aircraft - Registration: [N73034](https://openairdocs.org/aircraft/N73034), registered now, S/N 10242, built 1946 (OpenAirDocs) - Reported make and model: Cessna 120 - Registry model: [Cessna 120](https://openairdocs.org/model/cessna-120) (registry code 2071402) (OpenAirDocs) - Registry engine: [Continental C85 series](https://openairdocs.org/engine/continental-c85-series) (registry code 17008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 10242 - Airframe hours: 4936 - Engines: Continental C-90C 90 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Brook Mueller - Airworthiness certificate: Standard, Normal - Departed: RRL, Merrill, WI - Destination: Merrill, WI - Airport: RRL, Merrill Muni ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: none; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; last flight review October 29, 2002; seat: left; flight hours: 211 total, 54 in this make and model, 173 as pilot in command, 35 in the last 90 days, 11 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Dusk - Wind: 280° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 28 °F, dew point 18 °F - Altimeter: 29.94 inHg - Observed at: KRRL, 4 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 20040221003749A](https://openairdocs.org/incident/20040221003749A), Feb 21, 2004: Cessna 120, Merrill, WI, Substantial damage. (-23) On Saturday, February 21, 2004, at 1655 EST a Cessna CE-120, N73034, struck a rut in the snow with the right ski causing the aircraft to flip over while… ## Other investigations on N73034 (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 CEN23LA098](https://openairdocs.org/ntsb/CEN23LA098), Jan 25, 2023: Cessna 120 (N73034), Eagle River, WI, substantial damage. Probable cause: The pilot’s decision to takeoff from an unsuitable surface which resulted in collision with an object. 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.