# NTSB WPR11CA132: Cessna 170A, N9768A, Baker Lake, WA, February 11, 2011 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: February 10, 2011, 16:30 local (Feb 11, 2011, 00:30 UTC) - Place: Baker Lake, WA - Coordinates: 48.721942, -121.663612 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=48.7219&lon=-121.6636&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Nose over/nose down](https://openairdocs.org/ntsb-events/096) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report June 13, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 78331 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR11CA132 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78331/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78331 - Page: https://openairdocs.org/ntsb/WPR11CA132 ## Probable cause The pilot's encounter with soft terrain during an attempted takeoff from a dry lake bed. ## 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 170A, 3 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=2072304), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Runway/land/takeoff/taxi surface](https://openairdocs.org/ntsb-findings/03023000): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Cessna 170A, 1 case](https://openairdocs.org/ntsb-findings/03023000/cases.md?model=2072304), [All aircraft, 253 cases](https://openairdocs.org/ntsb-findings/03023000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Nose over/nose down](https://openairdocs.org/ntsb-events/096) (defining event); cases with it: [Cessna 170A, 14 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=2072304), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis According to the pilot, he performed about 20 touch-and-go practice takeoffs and landings on the dry lake bed prior to the accident. He stated that the terrain was mostly flat, but in places it was uneven and rough. During the last landing, the airplane's wheels became bogged down in the soft terrain, and the propeller struck the ground. The pilot shut down the engine, inspected the propeller, and examined the planned takeoff path for suitability. Thereafter, he attempted to depart. As the airplane accelerated, the left main landing gear encountered an area of soft dirt. The airplane impacted a berm whereupon it nosed over, bending the wing structure and the vertical stabilizer. The pilot further reported that no mechanical malfunction had precipitated the accident. ## Factual narrative According to the pilot, he performed about 20 touch-and-go landings on the dry lake bed prior to the accident. He stated that the terrain was mostly flat, but in places it was uneven and rough. During the last landing, the airplane's wheels became bogged down in the terrain, and the propeller struck the ground. The pilot shut down the engine, inspected the propeller, and examined the planned takeoff path for suitability. Thereafter, he attempted to depart. As the airplane accelerated, the left main landing gear encountered an area of soft dirt. The airplane impacted a berm whereupon it nosed over, bending the wing structure and the vertical stabilizer. The pilot further reported that no mechanical malfunction had precipitated the accident. ## Aircraft - Registration: [N9768A](https://openairdocs.org/aircraft/N9768A), registered now, S/N 19409, built 1950 (OpenAirDocs) - Reported make and model: CESSNA 170A - Registry model: [Cessna 170A](https://openairdocs.org/model/cessna-170a) (registry code 2072304) (OpenAirDocs) - Registry engine: [Continental C145 series](https://openairdocs.org/engine/continental-c145-series) (registry code 17012, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 19409 - Airframe hours: 2827 - Engines: CONT MOTOR C145 SERIES 145 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 22, 2010, 34 hours before - Departed: Baker Lake, WA - Destination: BVS, Burlington, WA ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; injuries: minor; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review November 3, 2009; seat: left; flight hours: 477 total, 184 in this make and model, 371 as pilot in command, 33 in the last 90 days, 28 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 39 °F ## 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 20110210002249A](https://openairdocs.org/incident/20110210002249A), Feb 10, 2011: Cessna 170A, Baker Lake, WA, Substantial damage. Pilot was practicing ldg & t.o. on lake bed. During t.o. run aircraft failured to clear berm (raised surface). Aircraft struck berm and flipped on back. ## Docket (1 files) The files NTSB released with the investigation on March 14, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78331. 601 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 601 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40344809&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.