# NTSB WPR11CA148: Cessna A150M, N7951V, Grass Valley, CA, February 27, 2011 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: February 27, 2011, 13:00 local (21:00 UTC) - Place: Grass Valley, CA - Coordinates: 39.221111, -121.001945 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.2211&lon=-121.0019&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report June 20, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 78447 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR11CA148 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78447/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78447 - Page: https://openairdocs.org/ntsb/WPR11CA148 ## Probable cause The aircraft's encounter with deep snow during the landing roll out. Contributing to the accident was the airport manager's failure to update the AWOS recording to reflect the closure of the runway due to snow. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Runway/land/takeoff/taxi surface: snow/slush/ice covered surface](https://openairdocs.org/ntsb-findings/03023015): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Cessna A150M, 1 case](https://openairdocs.org/ntsb-findings/03023015/cases.md?model=2071831), [All aircraft, 219 cases](https://openairdocs.org/ntsb-findings/03023015/cases.md) - [Airport facilities/design: runway/landing area condition](https://openairdocs.org/ntsb-findings/03017035): Environmental issues › Operating environment · Contributed to outcome (probable cause); cases with it: [Cessna A150M, 1 case](https://openairdocs.org/ntsb-findings/03017035/cases.md?model=2071831), [All aircraft, 61 cases](https://openairdocs.org/ntsb-findings/03017035/cases.md) - [Communication (personnel): lack of communication](https://openairdocs.org/ntsb-findings/02063510): Personnel issues › Task performance · Airport personnel (probable cause); cases with it: [Cessna A150M, 1 case](https://openairdocs.org/ntsb-findings/02063510/cases.md?model=2071831), [All aircraft, 84 cases](https://openairdocs.org/ntsb-findings/02063510/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) (defining event); cases with it: [Cessna A150M, 1 case](https://openairdocs.org/ntsb-events/096/sequence.md?model=2071831), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis Upon entering the airport environment, the pilot observed a snow-covered runway. He obtained an automated weather observation report (AWOS) from the non-towered airport, with no indication on the recording that the runway was closed. Shortly after touchdown, as the airplane began its roll out, the landing gear entered an area of 12-inch-deep snow and the airplane nosed over. After exiting the airplane, the pilot spoke to the airport manager who informed him that due to a power outage in the area, he had not been able to update the AWOS recording informing pilots of the runway closure due to snow. The airplane sustained substantial damage to the vertical stabilizer and to both wings. The pilot stated that there were no mechanical abnormalities with the airplane prior to the accident. ## Factual narrative Upon entering into the airport environment, the pilot observed a snow covered runway. He obtained an automated weather observation report (AWOS) for the non-towered airport, with no indication on the recording that the runway was closed. Shortly after touchdown, as the airplane began its roll out, the landing gear entered an area of 12-inch-deep snow and the airplane nosed over. After exiting the airplane, the pilot spoke to the airport manager who informed him that due to a power outage in the area, he had not been able to update the AWOS recording informing pilots of the runway closure due to snow. The airplane sustained substantial damage to the vertical stabilizer and to both wings. The pilot stated that there were no mechanical abnormalities with the airplane prior to the accident. ## Aircraft - Registration: [N7951V](https://openairdocs.org/deregistered/N7951V-2013-02-27), registration cancelled 2013-02-27, S/N A1500524, built 1974 (OpenAirDocs) - Reported make and model: CESSNA A150M - Registry model: [Cessna A150M](https://openairdocs.org/model/cessna-a150m) (registry code 2071831) (OpenAirDocs) - Registry engine: [Continental 0-200 series](https://openairdocs.org/engine/continental-0-200-series) (registry code 17020, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: A1500524 - Airframe hours: 2500 - Engines: CONT MOTOR O-200 SERIES 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Aerobatic - Last inspection: Annual, February 4, 2010, 85 hours before - Departed: RIU, Rancho Murieta, CA - Destination: GOO, Grass Valley, CA - Airport: GOO, Nevada County Air Park, runway 25, 4,350 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 60; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine sea, multi-engine land; instrument ratings: airplane, helicopter; medical: class 3, with waivers/limitations; last flight review August 4, 2009; seat: left; flight hours: 31,125 total, 650 in this make and model, 25,125 as pilot in command, 15 in the last 90 days, 35 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 32 °F, dew point 10 °F - Altimeter: 30.00 inHg - Observed at: BLU, 15 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 20110227002679A](https://openairdocs.org/incident/20110227002679A), Feb 27, 2011: Cessna A150M, Grass Valley, CA, Substantial damage. Pilot attempted landing at closed airport with 2.5 feet of snow covering the runway. After 30 feet the aircraft overturned. Pilot uninjured. Counceled pilot. ## Docket (1 files) The files NTSB released with the investigation on March 24, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78447. 514 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 514 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345331&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.