Dehavilland DHC-6 TWIN OTTER accident near Tullahoma, Tennessee, June 8, 2025
On June 8, 2025 at about 5:20 pm local time, a 1967 Dehavilland DHC-6 TWIN OTTER, registered N166DH, was substantially damaged in an accident during takeoff near Tullahoma, Tennessee (Tullahoma Rgnl/Wm Northern Fld airport). It was a skydiving flight under general aviation rules (Part 91). 6 people were seriously injured; 15 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 8, 2025 · about 5:20 pm local time · cases in 2025
- Place
- Tullahoma, Tennessee · Tullahoma Rgnl/Wm Northern Fld · cases near this airport · map
- Type
- Accident
- Injuries
- 6 people were seriously injured; 15 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Dehavilland DHC-6 TWIN OTTER, built 1967 · all DHC-6 TWIN OTTERs on the register
- Registration
- N166DH · registry record · serial 66
- Damage
- Substantial damage
- Flight
- Skydiving flight · general aviation rules (Part 91)
The NTSB's narrative preliminary · quoted from the NTSB record
On June 8, 2025, about 1220 central daylight time, a DeHavilland DHC-6 Twin Otter, N166DH, was involved in an accident near Tullahoma, Tennessee. The commercial pilot and five passengers were seriously injured, and 15 passengers were not injured. The flight was being conducted as a 14 Code of Federal Regulations Part 91 skydiving flight. The pilot was attempting to take off from runway 24 at the Tullahoma Regional Airport (THA), Tullahoma, TN. The accident flight was his fourth flight in the airplane that day. The pilot stated the takeoff was normal and he raised the flaps once the airplane was clear of obstacles. When the airplane was about 500 ft above the ground, the pilot noticed asymmetrical thrust on the engines while syncing the propellers. He said, “In the following seconds, I continued trying to sync the props and was getting unusual feedback in the controls. I didn’t notice any loss of power in the gauges, but something felt a miss.” The pilot lowered the nose of the airplane and saw the altitude level off, and airspeed decrease. The pilot determined that the left engine had lost power. He initiated “engine out procedures” and turned left, back to the airport to try and land on runway 36. The pilot could not remember if he secured the left engine; however, he did remember adding flaps as per the engine-out procedures. The pilot said he tried to maintain airspeed above the single-engine minimum control speed (Vmc), but the airplane continued to descend. The pilot was unable to make it back to the airport and chose to land in a field. There were two trees in the field that he was unable to avoid, and the airplane impacted the trees. The airplane came to rest upright, but the left wing, left engine and the tail section separated from the airframe, resulting in substantial damage. The right wing and engine remained secured to the airframe. There was no postimpact fire. The airplane wreckage was recovered and taken to a secure facility for further examination.
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
- Collision during takeoff/land during takeoff
- Loss of engine power (partial) during takeoff defining event
The aircraft
- Airframe total time: 26,616 hours
- Last inspection: approved inspection programme, September 10, 2024
- Landing gear: fixed
The flight
- Flight plan: none
- Runway 06/2, 5,501 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: from 270° at 14 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 3,800 ft
- Temperature: 81°F (27°C), dew point 64°F (18°C)
- Altimeter: 29.86 inHg
- Observation at 12:35 pm from KTHA
Weather report (METAR): METAR KTHA 081735Z AUTO 27014KT 10SM FEW038 FEW044 SCT055 27/18 A2986
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 5 | 15 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The NTSB has not released the docket for this case yet. The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), is usually released when the investigation is nearly complete, and the list here is refreshed when it appears. Check at the NTSB.
Other NTSB records under N166DH the same tail number, which may have belonged to a different aircraft at the time
Connections how this case links to the rest of the register
- N166DH on the register today · the tail number may have moved to another aircraft since
- Dehavilland DHC-6 114 registered today · the model family and its accident history
- Dehavilland 861 aircraft on the register
- Tullahoma Rgnl/Wm Northern Field · nearest airport
- Accidents and incidents in Tennessee 1,198 since 1982 · 231 in the last ten years
- Tennessee 6,533 aircraft registered
- Other NTSB records under N166DH 1 records · the number may have belonged to another aircraft at the time
The whole map of how records connect · these connections as data: /graph/accident/ERA25LA222.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.