# NTSB GAA16CA408: Bell Helicopter Textron 206, N206LW, Modesto, CA, July 30, 2016 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: July 30, 2016, 04:40 local (11:40 UTC) - Place: Modesto, CA - Coordinates: 37.624168, -120.949447 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=37.6242&lon=-120.9494&mi=10 - Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping) - Defining event: [Autorotation: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report September 12, 2016 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 93740 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA16CA408 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93740/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93740 - Page: https://openairdocs.org/ntsb/GAA16CA408 ## Probable cause The pilot's failure to maintain pitch control during an autorotation, which resulted in abnormal ground contact and main rotor contact with the tail boom. Contributing to the accident was the low fuel level which resulted in fuel starvation and a loss of engine power during the right turn to final. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: pitch control](https://openairdocs.org/ntsb-findings/01062022): Aircraft › Aircraft oper/perf/capability · Incorrect use/operation (probable cause); cases with it: [Bell Helicopter Textron 206L-1, 1 case](https://openairdocs.org/ntsb-findings/01062022/cases.md?model=1182107), [All aircraft, 526 cases](https://openairdocs.org/ntsb-findings/01062022/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Bell Helicopter Textron 206L-1, 8 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=1182107), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Bell Helicopter Textron 206L-1, 3 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=1182107), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Miscellaneous/other](https://openairdocs.org/ntsb-events/900); cases with it: [Bell Helicopter Textron 206L-1, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=1182107), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) - [Approach-VFR pattern final: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Bell Helicopter Textron 206L-1, 7 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=1182107), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Autorotation: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Bell Helicopter Textron 206L-1, 1 case](https://openairdocs.org/ntsb-events/900/sequence.md?model=1182107), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## Analysis The helicopter pilot reported that after a lengthy search and rescue mission he was headed back to the airport when the low fuel light illuminated, which meant there was about 10 minutes of fuel remaining. The pilot further reported that during the approach to land he made a right turn to final and the engine "flamed out". Subsequently, the pilot performed an emergency autorotation which resulted in abnormal ground contact and main rotor contact with the tail boom. After the landing, the passenger examined the helicopter and revealed that the tail boom sustained substantial damage. The pilot reported that prior to the loss of engine power, there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The loss of engine power reported by the pilot was likely the result of fuel starvation during the right turn to final. The pilot reported that the fuel level was not checked after the accident. ## Factual narrative The helicopter pilot reported that after a lengthy search and rescue mission he was headed back to the airport when the low fuel light illuminated, which meant there was about 10 minutes of fuel remaining. The pilot further reported that during the approach to land he made a right turn to final and the engine "flamed out". Subsequently, the pilot performed an emergency autorotation which resulted in abnormal ground contact and main rotor contact with the tail boom. After the landing, the passenger examined the helicopter and revealed that the tail boom sustained substantial damage. The pilot reported that prior to the loss of engine power, there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The loss of engine power reported by the pilot was likely the result of fuel starvation during the right turn to final. The pilot reported that the fuel level was not checked after the accident. ## Aircraft - Registration: [N206LW](https://openairdocs.org/aircraft/N206LW), registered now, S/N 45182, built 1978 (OpenAirDocs) - Reported make and model: BELL HELICOPTER TEXTRON 206 (L1) - Registry model: [Bell Helicopter Textron 206L-1](https://openairdocs.org/model/bell-helicopter-textron-206l-1) (registry code 1182107) (OpenAirDocs) - Registry engine: [Allison 250 SER 400HP](https://openairdocs.org/engine/allison-250-ser-400hp) (registry code 03013, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 45182 - Year built: 1978 - Airframe hours: 6720.5 - Engines: Rolls Royce C30 650 horsepower turbo shaft - Damage: Substantial damage - Flight: Public aircraft - local, Public use - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, July 10, 2016 - Departed: MOD, Modesto, CA - Destination: MOD, Modesto, CA - Airport: MOD, Modesto City-Co-Harry Sham Fld, runway 28R, 5,904 × 150 ft, asphalt - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; injuries: none; airline transport, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 2, with waivers/limitations; last flight review June 16, 2015; seat: right; restraint: 4-point; flight hours: 6,532 total, 3,700 in this make and model, 5,351 as pilot in command, 81 in the last 90 days, 18 in the last 30 days ## Weather - Conditions: Visual (VMC), Night - Wind: 330° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 79 °F, dew point 46 °F - Altimeter: 29.70 inHg - Observed at: KMOD ## 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 20160730025009A](https://openairdocs.org/incident/20160730025009A), Jul 30, 2016: Bell Helicopter Textron 206L-1, Modesto, CA, Substantial damage. At 4:40 am while returning from a hiker rescue mission with the stainislaus county sherrif's department in a Bell 206, the pilot was asked to return to the… ## Docket (4 files) The files NTSB released with the investigation on August 24, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93740. 1.5 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 847 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443655&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Memorandum for Record - Telephone Interview, Pilot (item 2, .PDF, 124 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443656&FileExtension=.PDF&FileName=Memorandum%20for%20Record%20-%20Telephone%20Interview,%20Pilot-Master.PDF - Email Exchange with Pilot (item 3, .PDF, 113 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443657&FileExtension=.PDF&FileName=Email%20Exchange%20with%20Pilot-Master.PDF - Accident Photo (Courtesy of Owner) (item 4, .PDF, 1 photo, 371 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40443658&FileExtension=.PDF&FileName=Accident%20Photo%20(Courtesy%20of%20Owner)-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.