# NTSB WPR10LA125: Schweizer G164B, N8494K, Byron, CA, February 23, 2010 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 23, 2010, 13:30 local (21:30 UTC) - Place: Byron, CA - Coordinates: 37.523887, -121.337776 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.5239&lon=-121.3378&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report July 18, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 75326 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR10LA125 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/75326/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=75326 - Page: https://openairdocs.org/ntsb/WPR10LA125 ## Probable cause A loss of engine power due to carburetor icing as a result of the pilot's failure to use carburetor heat. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Not specified (probable cause); cases with it: [Schweizer G-164B, 1 case](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=8059055), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) - [Temp/humidity/pressure: conducive to carburetor icing](https://openairdocs.org/ntsb-findings/03031030): Environmental issues › Conditions/weather/phenomena · Effect on equipment (probable cause); cases with it: [Schweizer G-164B, 1 case](https://openairdocs.org/ntsb-findings/03031030/cases.md?model=8059055), [All aircraft, 435 cases](https://openairdocs.org/ntsb-findings/03031030/cases.md) - [Use of equip/info: use of equip/system](https://openairdocs.org/ntsb-findings/02063015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Schweizer G-164B, 1 case](https://openairdocs.org/ntsb-findings/02063015/cases.md?model=8059055), [All aircraft, 1,391 cases](https://openairdocs.org/ntsb-findings/02063015/cases.md) - [Terrain](https://openairdocs.org/ntsb-findings/03021000): Environmental issues › Physical environment · Effect on operation; cases with it: [Schweizer G-164B, 2 cases](https://openairdocs.org/ntsb-findings/03021000/cases.md?model=8059055), [All aircraft, 267 cases](https://openairdocs.org/ntsb-findings/03021000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Schweizer G-164B, 2 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=8059055), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Schweizer G-164B, 4 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=8059055), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-flare/touchdown: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Schweizer G-164B, 7 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=8059055), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis After an aerial application flight, the pilot initiated a turn back toward the airstrip. The airplane's engine started to run rough and lose power. The pilot turned the airplane into the wind and initiated a forced landing into a deeply furrowed field. As the airplane touched down the landing gear sunk into the soft ground and the airplane nosed over, coming to a rest inverted. Postaccident examination of the airframe and an engine test run revealed no anomalies. The nearest weather reporting station reported a temperature of 9 degrees Celsius (C) and a dew point of 7 degrees C at the time of the accident. Review of the carburetor icing probability chart revealed that this temperature and dew point were conducive to serious icing at cruise power. ## Factual narrative On February 23, 2010, about 1330 Pacific standard time, a Schweizer Aircraft Corporation G-164B, N8494K, experienced a loss of engine power near Byron, California. Haley Flying Service, Inc., operated the airplane under the provisions of 14 Code of Federal Regulations Part 137 as an agricultural crop dusting operation. The airplane sustained substantial damage after making a forced landing on a soft dirt field and nosing over onto its back. The commercial pilot, the sole occupant, was not injured. Visual meteorological conditions were prevalent in the area, and no flight plan had been filed. The pilot reported that after finishing the application flight he initiated a turn towards the airstrip when the engine started to run rough and lose significant power. The pilot turned the airplane into the wind and initiated a forced landing into a deeply furrowed field. As the airplane touched down, the landing gear sunk into the soft ground and the airplane nosed over, coming to rest inverted. Postaccident examination of the airframe and engine revealed substantial damage to three of the four airplane’s wings, along with the vertical stabilizer and rudder. No visual anomalies were observed with the engine. The spark plugs were removed and appeared normal. The fuel system was examined and found to be clear of water and debris. The engine was started and no anomalies were noted. The nearest weather reporting station was located at Livermore Municipal Airport, Livermore, California, about 12 nautical miles southwest of the accident site. At 1253 it reported, overcast skies at 400 feet; light rain showers; temperature 9 degrees Celsius (C); dew point 7 degrees C; and an altimeter setting of 30.19 inches of mercury. Review of the carburetor icing probability chart revealed that the temperature and dew point at the time of the accident were conducive to serious icing at cruise power. ## Aircraft - Registration: [N8494K](https://openairdocs.org/aircraft/N8494K), registered now, S/N 713B, built 1983 (OpenAirDocs) - Reported make and model: Schweizer Aircraft Corp G164B - Registry model: [Schweizer G-164B](https://openairdocs.org/model/schweizer-g-164b) (registry code 8059055) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 713B - Airframe hours: 10294 - Engines: Pratt and Whitney R1340 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Haley Flying Service, Inc. - Registered owner: Haley Flying Service, Inc. - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, December 23, 2009, 36 hours before - Departed: Tracy, CA - Destination: Tracy, CA - Airport: Haley F.S. Airstrip ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; injuries: none; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review January 28, 2010; seat: single; flight hours: 2,581 total, 631 in this make and model, 2,199 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 7 statute miles - Lowest ceiling: 400 ft overcast - Temperature: 48 °F, dew point 45 °F - Altimeter: 30.19 inHg - Observed at: LVK, 12 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 20100223028539A](https://openairdocs.org/incident/20100223028539A), Feb 23, 2010: Schweizer A G-164B, Byron, CA, Substantial damage. Operator was conducting operations under the provisions of 14 CFR part 137. Pilot had just finished up applying a load of urea and was heading back to the… ## Other investigations on N8494K (2) 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 WPR18LA015](https://openairdocs.org/ntsb/WPR18LA015), Oct 24, 2017: Schweizer G 164B (N8494K), Tracy, CA, substantial damage. Probable cause: The pilot's failure to maintain directional control of the airplane during the landing roll. - [NTSB MKC86LA155](https://openairdocs.org/ntsb/MKC86LA155), Jul 23, 1986: Schweizer G-164B (N8494K), Harrisburg, AR, substantial damage ## Docket (2 files) The files NTSB released with the investigation on June 8, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=75326. 330 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 289 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347043&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Email Correspondence - Engine Examination (item 2, .PDF, 41 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40347044&FileExtension=.PDF&FileName=Email%20Correspondence%20-%20Engine%20Examination-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.