CEN19FA024 · Bell 206 B
W T Byler Bell 206 B · Accident: controlled flight into terrain/object (CFIT) en route
From Private Ranch, TX to San Antonio International Airport (SAT)
Event
- NTSB case
- CEN19FA024
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 3 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Bell 206 B
- Aircraft type
- Bell 206
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N417WT
- Operator
- W T Byler
- Onboard fatalities
- Unknown
- Route
- From Private Ranch, TXTo San Antonio International Airport (SAT), San Antonio, TX
- Aircraft age
- About 13 years (built 2005)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Controlled flight into terrain/object (CFIT)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Environmental issues › Conditions/weather/phenomena
- Personnel issues › Action/decision
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot and two passengers onboard the turboshaft-powered helicopter departed from a private ranch on a night cross-country flight in visual meteorological conditions. Video evidence from witnesses who observed the departure showed that bright flood lights were shown directly at the helicopter during the departure. The helicopter impacted terrain shortly after takeoff about 100 ft below the top of a 1,500-ft hill and about 5 miles east of the departure point.
An automated weather station, located 13 miles southeast of the departure site, at 0015 recorded, clear skies, and an altimeter setting of 29.97 inHg. A review of weather information about the time of the accident revealed a small area of cloud ceilings east of the departure point. Based upon the helicopter's recorded route of flight, it is unlikely that the helicopter encountered this area of reduced visibility/ceilings.
Examination of the helicopter revealed no evidence of any mechanical malfunctions or anomalies that would have precluded normal operation. Data from the helicopter's flight displays revealed that the helicopter's altimeter was set at 30.05 inches of mercury (inHg); The altimeter setting at the station nearest the accident site was 29.97 inHg. This difference would have resulted in the helicopter's altimeter indicating a higher altitude than the helicopter's actual altitude. The display's data also indicated the helicopter's flight path towards its destination airport. The flight display's last indicated altitude was 1,538 ft, which would have only provided marginal obstacle clearance.
Additionally, the helicopter's terrain avoidance and warning system low altitude alerts were set to "inhibit", or turned off; therefore, the pilot would not have received a terrain warning message. Flight information from the displays did not record any evasive maneuvering, and it is likely that the pilot did not see the terrain before impact.
Autopsy and toxicology testing of the pilot did not reveal evidence of incapacitation. A review of the pilot's medical information indicated that he had been diagnosed with early cataracts; the pilot first reported cataracts to the FAA in 2005, and it is possible that they could have increased in severity enough to have compromised his night vision and contributed to his difficulty avoiding the hill. Additionally, the pilot's eyesight may not have adjusted to the night conditions after being exposed to bright lights during departure. However, the severity of his cataracts at the time of the accident is unknown, and whether visual limitations from cataracts or bright lights contributed to the accident, could not be determined.
The accident is consistent with control flight into terrain during dark night conditions
Probable cause
The pilot's controlled flight into terrain during night visual meteorological conditions. Contributing to the accident was the pilot improper decision to inhibit the helicopter's terrain warning systems and flight at low altitude.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN19FA024
- Event ID
- 20181104X01658
- Case number
- CEN19FA024
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2018-11-04.
- API snapshot SHA-256: ee93a356e567808b021b141b5b94b51486614abd9980258e3e893c38ad61173b; retrieved 2026-09-15T06:50:28.207Z.