# NTSB GAA18CA221: Cessna 120, N1807V, Iola, WI, April 21, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: April 21, 2018, 12:30 local (17:30 UTC) - Place: Iola, WI - Coordinates: 44.505554, -89.025001 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.5056&lon=-89.0250&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff-rejected takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 24, 2018 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 97073 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA18CA221 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97073/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97073 - Page: https://openairdocs.org/ntsb/GAA18CA221 ## Probable cause The pilot’s decision to reject the takeoff from a snow-covered grass surface, which resulted in a nose-over. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Cessna 120, 9 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=2071402), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Runway/land/takeoff/taxi surface: snow/slush/ice covered surface](https://openairdocs.org/ntsb-findings/03023015): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Cessna 120, 3 cases](https://openairdocs.org/ntsb-findings/03023015/cases.md?model=2071402), [All aircraft, 219 cases](https://openairdocs.org/ntsb-findings/03023015/cases.md) - [Performance/control parameters: pitch control](https://openairdocs.org/ntsb-findings/01062022): Aircraft › Aircraft oper/perf/capability · Not attained/maintained; cases with it: [Cessna 120, 2 cases](https://openairdocs.org/ntsb-findings/01062022/cases.md?model=2071402), [All aircraft, 526 cases](https://openairdocs.org/ntsb-findings/01062022/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff-rejected takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Cessna 120, 6 cases](https://openairdocs.org/ntsb-events/490/sequence.md?model=2071402), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) - [Takeoff: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Cessna 120, 20 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=2071402), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis According to the pilot in the tailwheel-equipped airplane with 26-inch bush tires installed, he intended to perform several ground runs to pack the wet, snow-covered grass surface and then take off. During the start of the first ground run, the airplane accelerated quickly, and the pilot decided to take off. He reported that he believed that the airplane had entered an area of deeper snow and "thought it would be safer and more conservative to stop." He did not realize the airplane had become airborne. The pilot decreased the throttle to idle, and the airplane then decelerated and nosed over. The airplane sustained substantial damage to the right-wing lift strut. In the recommendation section of the National Transportation Safety Board Pilot Aircraft Accident Report, the pilot asserted that the accident could have been prevented if he had "assumed that the conditions were unacceptable as I could not ascertain with absolute certainty that the surface was acceptable." The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation. ## Factual narrative According to the pilot in the tailwheel-equipped airplane with 26" bush tires installed, his intent was to perform several ground runs to pack the wet snow-covered grass surface, and then takeoff. During the start of the first ground run, the airplane accelerated quickly, and the pilot decided to takeoff. He reported that he did not realize the airplane had become airborne, rather, he believed that the airplane had entered an area of deeper snow, and he "thought it would be safer and more conservative to stop." The pilot decreased the throttle to idle, the airplane decelerated and nosed over. The airplane sustained substantial damage to the right-wing lift strut. Per the National Transportation Safety Board, Pilot Aircraft Accident Report, in the Recommendation section, the pilot asserted that the accident could have been prevented if he had, "assumed that the conditions were unacceptable as I could not ascertain with absolute certainty that the surface was acceptable." The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation. ## Aircraft - Registration: [N1807V](https://openairdocs.org/aircraft/N1807V), registered now, S/N 13992, built 1947 (OpenAirDocs) - Reported make and model: CESSNA 120 (NO SERIES) - 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: 13992 - Year built: 1947 - Airframe hours: 3153 - Engines: Continental C85 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 12, 2017 - Departed: W23, Wild Rose, WI - Destination: 68C, Iola, WI - Airport: 68C, Central County, runway 27, 1,800 × 120 ft, grass/turf - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 39; injuries: none; airline transport; airplane ratings: single-engine land, single-engine sea, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review December 3, 2017; seat: left; restraint: 4-point; flight hours: 10,425 total, 350 in this make and model, 4,701 as pilot in command, 276 in the last 90 days, 103 in the last 30 days, 1.5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 130° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 57 °F, dew point 16 °F - Altimeter: 30.42 inHg - Observed at: KPCZ, 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 20180421003949A](https://openairdocs.org/incident/20180421003949A), Apr 21, 2018: Cessna 120, Iola, WI, Substantial damage. Aircraft was performing intersection departure on snow covered runway with approximately 1200 feet of usable runway. Pilot stated that, during takeoff roll, he… ## Docket (2 files) The files NTSB released with the investigation on August 28, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97073. 3.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40466099&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Photo (item 2, .PDF, 207 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40466100&FileExtension=.PDF&FileName=Photo-Master.PDF 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.