# NTSB CEN18LA260: Bell 206, N224KM, Bentley, IL, July 6, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 6, 2018, 17:15 local (22:15 UTC) - Place: Bentley, IL - Coordinates: 40.330001, -91.18 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.3300&lon=-91.1800&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Fuel starvation](https://openairdocs.org/ntsb-events/191) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 20, 2020 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Flight Standards District Office - NTSB case key (mKey): 97707 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN18LA260 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97707/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97707 - Page: https://openairdocs.org/ntsb/CEN18LA260 ## Probable cause The pilot's failure to ensure that adequate fuel was on board for the maneuvering flight, which resulted in a total loss of engine power due to fuel starvation. ## 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: [Bell 206B, 13 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=1181511), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Fuel system](https://openairdocs.org/ntsb-findings/01022800): Aircraft › Aircraft systems · Incorrect use/operation (probable cause); cases with it: [Bell 206B, 2 cases](https://openairdocs.org/ntsb-findings/01022800/cases.md?model=1181511), [All aircraft, 181 cases](https://openairdocs.org/ntsb-findings/01022800/cases.md) - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Bell 206B, 15 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=1181511), [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. - [Maneuvering-low-alt flying: Fuel starvation](https://openairdocs.org/ntsb-events/191) (defining event); cases with it: [Bell 206B, 3 cases](https://openairdocs.org/ntsb-events/191/sequence.md?model=1181511), [All aircraft, 733 cases](https://openairdocs.org/ntsb-events/191/sequence.md) - [Autorotation: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Bell 206B, 28 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=1181511), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) ## Analysis The commercial helicopter pilot indicated that, about 10 minutes after takeoff, while making a turn during an aerial application flight, he noticed the low fuel pressure light illuminate; the fuel pressure gage indicated 0 psi, and the fuel quantity gage indicated 15 gallons. The engine subsequently lost total power, and the pilot performed an autorotation in preparation for a forced landing, during which the helicopter nosed over and sustained damage to the main and tail rotors. Postaccident examination of the helicopter revealed that the fuel quantity gage read 4 gallons, and the fuel tank contained about 9.5 gallons of fuel. Both fuel boost pumps tested normally. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The helicopter's flight manual stated to land as soon as practical when fuel quantity was less than 20 gallons and contained a warning that uncoordinated turns and maneuvers were to be avoided with a fuel quantity of less than 20 gallons. The manual also stated that, due to possible fuel sloshing in unusual attitudes or out-of-trim conditions and one or both fuel boost pumps inoperative, the unusable fuel was 10 gallons. The turn during spray operations with less than 20 gallons of fuel likely caused the fuel to unport, allowing air into the fuel line. This resulted in a total loss of engine power due to fuel starvation. The pilot did not ensure that adequate fuel was on board for the maneuvering flight. ## Factual narrative On July 6, 2018, about 1715 central daylight time, a Bell 206B helicopter, N224KM, was substantially damaged during a forced landing near Bentley, Illinois. The pilot was not injured. The helicopter was registered to and operated by Woodley Aerial Leasing LLC under the provisions of Title 14 Code of Federal Regulations Part 137 as an aerial application flight. Day visual meteorological conditions prevailed for the local flight, which departed about 1705 from a load truck near Bentley, Illinois. According to the pilot, he departed the load truck and flew about 1.5 miles east to an application area. While making a turn, he noticed the low fuel pressure light illuminate. After initiating a climb, he noticed the fuel quantity gage indicated 15 gallons and the fuel pressure gage indicated zero psi. The pilot initiated an autorotation in preparation for a forced landing. During touchdown, the helicopter nosed over, which damaged the main and tail rotors. Examination of the helicopter revealed the fuel quantity gage read about 4 gallons. About 1.5 quarts of fuel were drained from the airframe and filter sumps, with no anomalies observed. The fuel valve switch was found in the on position. The forward and aft fuel boost pumps were tested individually, with normal pressures observed. The fuel tank was drained, revealing that about 9.5 gallons of total fuel were present in the tank. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal flight operations. The helicopter's flight manual stated to land as soon as practical when fuel quantity was less than 20 gallons. The flight manual contained a warning that uncoordinated turns and maneuvers were to be avoided with a fuel quantity of less than 20 gallons and also stated that due to possible fuel sloshing in unusual attitudes or out of trim conditions and one or both fuel boost pumps inoperative, unusable fuel was 10 gallons. ## Aircraft - Registration: [N224KM](https://openairdocs.org/aircraft/N224KM), registered now, S/N 1124 (OpenAirDocs) - Reported make and model: Bell 206 (B) - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs) - Registry engine: [Allison 250-C20](https://openairdocs.org/engine/allison-250-c20) (registry code 03080, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 1124 - Year built: 1974 - Airframe hours: 10389 - Engines: Allison 250-C20 400 horsepower turbo shaft - Damage: Substantial damage - Flight: Aerial application, Part 137 - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, October 1, 2017 - Departed: Bentley, IL - Destination: Bentley, IL ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: none; commercial, flight instructor; instrument ratings: helicopter; medical: class 2, without waivers/limitations; last flight review November 5, 2017; seat: right; restraint: 4-point; flight hours: 3,286 total, 977 in this make and model, 3,126 as pilot in command, 160 in the last 90 days, 80 in the last 30 days, 10 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 7 knots, gusting 12 - Visibility: 10 statute miles - Temperature: 82 °F, dew point 64 °F - Altimeter: 30.29 inHg - Observed at: KEOK, 14 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 20180706009229A](https://openairdocs.org/incident/20180706009229A), Jul 6, 2018: Bell 206B, Carthage, IL, Substantial damage. Pilot was performing aerial application operations. During a repositioning turn/maneuver, the pilot stated that the fuel pump/pressure warning light… ## Docket (3 files) The files NTSB released with the investigation on November 8, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97707. 3.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 445 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40477896&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Examination Information (item 2, .PDF, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40477898&FileExtension=.PDF&FileName=Examination%20Information-Master.PDF - Flight Manual -- Excerpt of Fuel Information Pages (item 3, .PDF, 221 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40477899&FileExtension=.PDF&FileName=Flight%20Manual%20--%20Excerpt%20of%20Fuel%20Information%20Pages-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.