# NTSB GAA18CA523: Eggleston Daniel S-18 Thorp, N575DG, Porterville, CA, September 1, 2018 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: September 1, 2018, 09:10 local (16:10 UTC) - Place: Porterville, CA - Coordinates: 36.029445, -119.056388 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=36.0294&lon=-119.0564&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report March 18, 2019 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 98226 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA18CA523 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/98226/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=98226 - Page: https://openairdocs.org/ntsb/GAA18CA523 ## Probable cause The pilot’s failure to maintain directional control during the takeoff roll. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=05624OM), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=05624OM), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Contributed to outcome; cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=05624OM), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-events/230/sequence.md?model=05624OM), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Takeoff: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=05624OM), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Takeoff: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-events/300/sequence.md?model=05624OM), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) - [Takeoff: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Eggleston Daniel S-18 THORP, 1 case](https://openairdocs.org/ntsb-events/096/sequence.md?model=05624OM), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot of the tailwheel-equipped airplane reported that, during takeoff, he advanced the throttle to full power, maintained the runway centerline, and began to raise the tail. He added that, about 60 mph, the airplane suddenly turned left. He applied full right rudder to no avail. Subsequently, the airplane continued to veer left, exited the runway into plowed dirt, and nosed over. The airplane sustained substantial damage to the fuselage and vertical stabilizer. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The automated weather observation system at the airport reported that, about the time of the accident, the wind was variable at 3 knots. The pilot was departing from runway 30. ## Factual narrative The pilot of the tailwheel-equipped airplane reported that, during takeoff, he advanced the throttle to full power, maintained the runway centerline, and began to raise the tail. He added that about 60 mph, the airplane suddenly turned left. He applied full right rudder to no avail. Subsequently, the airplane continued to veer left, exited the runway into plowed dirt, and nosed over. The airplane sustained substantial damage to the fuselage and vertical stabilizer. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The automated weather observation system at the accident airport reported that, about the time of the accident, the wind was variable at 3 knots. The pilot was departing on runway 30. ## Aircraft - Registration: [N575DG](https://openairdocs.org/aircraft/N575DG), registered now, S/N 218 (OpenAirDocs) - Reported make and model: Eggleston Daniel S-18 THORP - Registry model: [Eggleston Daniel S-18 THORP](https://openairdocs.org/model/eggleston-daniel-s-18-thorp) (registry code 05624OM) (OpenAirDocs) - Registry engine: [Lycoming O-320-E2D](https://openairdocs.org/engine/lycoming-o-320-e2d) (registry code 42123, 4 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 218 - Year built: 2007 - Airframe hours: 348.4 - Engines: Lycoming O-320-E2D 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, July 21, 2018 - Departed: O42, Woodlake, CA - Destination: PTV, Porterville, CA - Airport: PTV, Porterville Muni, runway 30, 5,960 × 150 ft, asphalt - Equipment: Electronic flight bag or handheld device, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 45; injuries: minor; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review June 28, 2017; seat: left; restraint: 4-point; flight hours: 209 total, 12 in this make and model, 160 as pilot in command, 18 in the last 90 days, 7 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 8 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 59 °F - Altimeter: 29.89 inHg - Observed at: KPTV ## 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 20180901012879A](https://openairdocs.org/incident/20180901012879A), Sep 1, 2018: Eggleston Daniel S-18 THORP, Porterville, CA, Substantial damage. On September 2, 2018 N575DG, an amateur built S-18 thorp was taking off runway 30 at the Porterville municipal airport (kptv), when the pilot lost control of… ## Docket (1 files) The files NTSB released with the investigation on November 6, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=98226. 1.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40468060&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-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.