# NTSB ERA18LA271: Bell OH 58A, N206WH, Juana Diaz, PR, September 24, 2018 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 3 · Limited · Final report - Date: September 24, 2018, 17:30 local (21:30 UTC) - Place: Juana Diaz, PR - Coordinates: 18.220479, -66.58992 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=18.2205&lon=-66.5899&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Minor injuries - Injuries: 3 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA FSDO - NTSB case key (mKey): 98453 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA18LA271 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/98453/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=98453 - Page: https://openairdocs.org/ntsb/ERA18LA271 ## Probable cause A total loss of engine power for reasons that could not be determined based on the available information. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Bell OH-58A, 8 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=1181579), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Bell OH-58A, 5 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=1181579), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Autorotation: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell OH-58A, 12 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181579), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis About 1 month before the accident flight, the helicopter, which had not been flown in about 7 years, was fueled with about 40 gallons of fuel, of which 3 gallons were drained to remove potential contamination. The helicopter was flown 1.8 hours between the fueling and the accident flight. There was no record of additional fuel being added between those flights and the accident flight. About 15 minutes after departing on the accident flight, between 500 and 1,000 ft above ground level (agl), the engine lost total power. The pilot performed an autorotation and landed on level, soft terrain, the helicopter tipped forward onto the nose, and the pilot applied aft cyclic to correct. The main rotor blades impacted the tailboom, severing it from the helicopter, and the main rotor transmission and rotor head separated from the mount. The helicopter was not recovered and could not be examined after the accident. The amount of fuel onboard at the time of departure could not be determined. Based on the available information, the reason for the loss of engine power could not be determined. ## Factual narrative On September 24, 2018, about 1730 eastern daylight time, a Bell OH58A, N206WH, was substantially damaged when it was involved in an accident near Juana Diaz, Puerto Rico. The commercial pilot and two passengers sustained minor injuries. The helicopter was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to maintenance records, the helicopter was last operated on September 10, 2011, about 7 years before the accident flight. On August 27, 2018, the helicopter was fueled with about 40 gallons of fuel, then subsequently drained of about 3 gallons to remove any potential contamination. Subsequent maintenance was performed on September 2, 2018, followed by a 1.1-hour test flight and a subsequent .7-hour flight. There was no record of additional fueling between the two dates. The pilot reported that there were no mechanical issues or other anomalies noticed during the previous flights. After conducting the second test flight the morning of the accident, he informed the owner that the helicopter was airworthy, and they could perform the flight. About 15 minutes after departure on the accident flight, between 500 and 1,000 ft above ground level (agl), and with no warning, the engine stopped producing power. The pilot performed an autorotation and landed on level, soft terrain. Upon touchdown the helicopter began to go forward onto its nose, and the pilot applied aft cyclic to correct, which resulted in the main rotor blades impacting the tail boom. The helicopter spun around 180° before coming to rest upright. Examination of the helicopter revealed that the tail boom separated aft of the horizontal stabilizer fins and the transmission and rotor head separated from the mount. The helicopter was not recovered for additional examination or fuel sample collection due to accident site logistics and weather conditions. According to the engine manufacturer, the helicopter’s fuel consumption rate was about 190 pounds (28 gallons) per hour during cruise flight. The helicopter likely consumed about 342 pounds (50 gallons) during the 1.8 hours flight time before the accident flight. The fuel tank had a total capacity of 72 usable gallons. The amount of fuel onboard at the time of departure could not be determined. ## Aircraft - Registration: [N206WH](https://openairdocs.org/deregistered/N206WH-2020-06-22), registration cancelled 2020-06-22, S/N 72-21362 (OpenAirDocs) - Reported make and model: Bell OH 58A (No Series) - Registry model: [Bell OH-58A](https://openairdocs.org/model/bell-oh-58a) (registry code 1181579) (OpenAirDocs) - Registry engine: [Allison T63-A-700](https://openairdocs.org/engine/allison-t63-a-700) (registry code 03086, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 72-21362 - Year built: 1972 - Airframe hours: 303.8 - Engines: Rolls-Royce T63-A-700 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, September 1, 2018, 2 hours before - Departed: TJPS, Ponce, PR - Destination: TJPS, Ponce, PR - Airport: JPS, Mercedita - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; injuries: minor; commercial; medical: class 2, without waivers/limitations; last flight review March 9, 2018; seat: right; restraint: 3-point; flight hours: 1,530 total, 200.3 in this make and model, 28.1 in the last 90 days, 11.6 in the last 30 days, 1.7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 100° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 9,500 ft broken - Temperature: 81 °F, dew point 72 °F - Altimeter: 29.95 inHg - Observed at: JPS, 38 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 20180924019219A](https://openairdocs.org/incident/20180924019219A), Sep 24, 2018: Bell OH-58A, Juana Diaz, PR, Destroyed. 09/24/2018, Helicopter Bell OH-58A N206WH departed mercedita airport (tjps) at/around 1515 hrs. With two passengers in a private flight. According to pilot in… ## Docket (6 files) The files NTSB released with the investigation on June 15, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=98453. 5.9 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 567 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=7059742&FileExtension=pdf&FileName=Pilots%206120%20Accident%20Report_Redacted-Rel.pdf - Record of conversation_FAA and rolls royce (item 2, PDF, 2 pages, 128 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11670055&FileExtension=pdf&FileName=Record%20of%20Conversation_FAA%20and%20Rolls%20Royce-Rel.pdf - Memo for record_ fuel burn (item 3, PDF, 1 page, 289 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11669586&FileExtension=pdf&FileName=Memorandum%20for%20Record_Fuel%20Burn-Rel.pdf - Pilot logbook excerpt (item 4, PDF, 4 pages, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11667988&FileExtension=pdf&FileName=Pilots%20Logbook%20Excerpt_Redacted-Rel.pdf - Maintenance records excerpt (item 5, PDF, 3 pages, 2.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11668953&FileExtension=pdf&FileName=MX%20Records%20Excerpt_Redacted-Rel.pdf - Photo array_accident site and helicopter damage (item 6, PDF, 1 page, 635 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11669283&FileExtension=pdf&FileName=Accident%20Site%20and%20Damage%20Photographs-Rel.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.