Bell 206 accident near Clark, Missouri, March 5, 2020
On March 5, 2020, a 1979 Bell 206 (helicopter), registered N32AE, was substantially damaged in an accident during enroute near Clark, Missouri. It was flown under charter and air-taxi rules (Part 135). No one was hurt; 4 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The fatigue failure of the pneumatic line for reasons that could not be determined, which resulted in a loss of engine power and subsequent hard landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 5, 2020
- Place
- Clark, Missouri · map
- Type
- Accident
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 206 L1, built 1979 · all 206s on the register
- Registration
- N32AE · registry record · serial 45327
- Damage
- Substantial damage
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The pilot of the helicopter air ambulance flight reported that, while en route on the night patient transfer flight, he received low rotor rpm warnings and engine power dropped below 90%. He reduced collective and turned toward a field to perform a precautionary landing, during which the helicopter touched down hard, resulting in substantial damage to the tail boom. A postaccident examination of the helicopter revealed that a pneumatic line, which had been leak-checked about 115 hours before the accident flight, had separated near its filter connection. A leak in the pneumatic line can cause the engine control system to enter a sub-idle fuel flow condition, resulting in a loss of engine power. An examination of the pneumatic line and filter revealed that the tube had fractured completely through at the toe of the weld between the tube and its filter fitting. Surface smearing was present on sections of the separation; however, the separation exhibited surfaces consistent with fatigue that initiated near the top of the tube. The tube's outer diameter surface near the elbow separation exhibited rub damage. A red ribbed hose was present in the engine bay near the tube separation and the ribbed hose exhibited discoloration on its outer surface consistent with rubbing against the pneumatic tube. One weld exceeded its component specification; the remaining tube and weld measurements met their component specifications. The tube, fitting, and weld materials met specifications. According to the engine manufacturer, the accident was the first occurrence of a separation involving this revision of the pneumatic line over 17 million fleetwide flight hours. The cause of the fatigue could not be attributed to the hose and pneumatic tube rubbing or any other issue, and the reason for the failure could not be determined based on the available information.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Loss of engine power (partial) during enroute defining event
- Off-field or emergency landing during emergency descent
- Hard landing during landing
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine fuel and control › Fuel controlling system › Failure
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Environmental issues › Conditions/weather/phenomena › Light condition › Dark › Contributed to outcome
Pilot
- Certificate: commercial pilot
- Ratings: instrument: helicopter; rotorcraft: helicopter
- Flight time: 5,252 hours in all; 383 in this make and model; 7 in the last 90 days; 5 in the last 30 days; 4,221 as pilot in command
- Last flight review: February 29, 2020
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 27,820.7 hours
- Last inspection: 100-hour inspection, February 13, 2020
- Maximum gross weight: 4,150 lb
- Seats: 4
- Landing gear: fixed
- Engine: Rolls Royce 250-C30P (turboshaft); 20,606 hours total
- Operator: Air Evac Ems Inc
The flight
- Departed from: MU92 Kirksville MO
- Destination: 91MO Columbia MO
Weather at the time
- Light: night
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 48°F (9°C), dew point 28°F (-2°C)
- Altimeter: 30.05 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 3 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
12 documents, released by the NTSB on January 14, 2021. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.