Bell 407 accident near Union Center, South Dakota, March 3, 2019
On March 3, 2019 at about 7:13 am local time, a 2013 Bell 407 (helicopter), registered N450AM, was substantially damaged in an accident during standing (engine(s) shutdown) near Union Center, South Dakota. It was flown under charter and air-taxi rules (Part 135). 1 person had minor injuries; 2 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The ambulance driver’s failure to see the helicopter’s rotating main rotor blades in dark night conditions, which resulted in the ambulance’s inadvertent collision with the helicopter. Contributing to the accident was the ambulance driver's failure to follow procedures when approaching the helicopter.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 3, 2019 · about 7:13 am local time
- Place
- Union Center, South Dakota · map
- Type
- Accident
- Injuries
- 1 person had minor injuries; 2 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 407, built 2013 · all 407s on the register
- Registration
- N450AM · registry record · serial 54435
- Damage
- Substantial damage
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The helicopter pilot, flight nurse, and flight paramedic had arrived at a landing zone to pick up a patient at night. After landing, the pilot rolled the engine throttle to idle and briefed the flight crew that they were clear to depart the helicopter. About 20 seconds later, the ground ambulance drove toward the helicopter, and the main rotor blades impacted the top of the ambulance. The flight paramedic was thrown to the ground and sustained minor injuries. The main rotor blades, tailboom, and fuselage sustained substantial damage. The ground ambulance driver stated that he saw the crew open the doors and get out of the helicopter, so he moved the ambulance ahead to get closer to the helicopter. The driver stated that he did not realize "that the helicopter blades were still rotating." The operator confirmed that the ambulance driver had received training, which indicated that ground personnel are not to approach the helicopter until the blades had stopped rotation. In addition, the general operations manual stated that ground personnel will not come beneath the rotor disk until directed to do so by the pilot.
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
- Ground collision during standing (engine(s) shutdown) defining event
The NTSB's findings
- cause Personnel issues › Physical › Sensory ability/limitation › Visual function › Ground crew
- cause Environmental issues › Conditions/weather/phenomena › Light condition › Dark › Effect on personnel
- factor Personnel issues › Action/decision › Action › Incorrect action selection › Ground crew
Pilot
- Certificate: commercial pilot, private
- Ratings: single-engine land; instrument: helicopter; rotorcraft: helicopter
- Flight time: 2,138 hours in all; 130 in this make and model; 18 in the last 90 days; 2 in the last 30 days; 2,138 as pilot in command
- Last flight review: November 27, 2018
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 2,105 hours
- Last inspection: continuous airworthiness programme, March 1, 2019
- Maximum gross weight: 5,250 lb
- Seats: 4
- Landing gear: fixed
- Engine: Rolls Royce 250-C47B (turboshaft); 2,133 hours total
- Operator: Air Methods Corp
The flight
- Departed from: KSPF Spearfish SD at 6:37 am
- Destination: Union Center SD
Weather at the time
- Light: night, dark
- Wind: from 330° at 13 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: -11°F (-24°C), dew point -20°F (-29°C)
- Altimeter: 30.42 inHg
- Observation at 7:52 am from KRAP
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
4 documents, released by the NTSB on January 15, 2020. 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.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Pilot, Flight Crew, Driver Statements | PDF, 5 pages | View Download |
| 3 | Accident Report Photographs | PDF, 4 pages | View Download |
| 4 | General Operations Manual, Training Excerpts | PDF, 4 pages | View Download |
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.