De Havilland DHC-6 TWIN OTTER N166DH
8 June 2025 · Tullahoma, Tennessee, United States · Serious injuries
Summary
On 8 June 2025 at about 17:20 local time, a De Havilland DHC-6 TWIN OTTER registered N166DH was involved in an accident near Tullahoma, Tennessee, United States. 21 people were on board and 6 were seriously injured. The aircraft was substantially damaged. No probable cause has been published yet; this accident is still under investigation.
The record
- Date
- at 17:20
- Classification
- Accident
- Location
- Tullahoma, Tennessee, United States
- Nearest airport
- Tullahoma Rgnl/Wm Northern Fld (THA)
- Coordinates
- 35.3801, -86.2468
- Aircraft
- De Havilland DHC-6 TWIN OTTER
- Registration
- N166DH
- Category
- Airplane
- Year built
- 1967
- Engines
- 2
- Operator
- Not recorded
- Operating rule
- Part 91: General Aviation
- Purpose of flight
- Skydiving
- Phase of flight
- Not recorded
- Aircraft damage
- Substantial
- Weather
- VMC
- Light
- Day
- NTSB number
- ERA25LA222
People
6 people were seriously injured.
| On board | Died | Serious | Minor | Uninjured |
|---|---|---|---|---|
| 21 | 0 | 6 | 0 | 15 |
Probable cause
The NTSB has not published a probable cause for this record. The investigation is still open; a final report usually follows one to two years after the accident.
Nothing about the cause is stated here that is not in the source record.
Read the full NTSB narrative
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.
Quoted verbatim from the NTSB record.
Other De Havilland DHC-6 accidents
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 9 Aug 2025 | De Havilland DHC-6-300 | Whitmore, Arizona, United States | Grand Canyon Airlines Inc | Minor injuries | - |
| 6 May 2025 | De Havilland DHC-6-300 | Boulder City, Nevada, United States | Monarch Enterprises Inc | No injuries | - |
| 11 Aug 2025 | De Havilland DHC-6-300 | San Celmente, California, United States | Rampart Aviation | No injuries | - |
| 15 Nov 2024 | De Havilland DHC-6-300 | Boulder City, Nevada, United States | Grand Canyon Airlines, Inc. | No injuries | - |
| 21 Mar 2018 | De Havilland DHC 6 TWIN OTTER | Arctic Ocean, United States | Bald Mountain Air Service Inc | Serious injuries | - |
| 24 May 2017 | De Havilland DHC 6 | Perris, California, United States | - | No injuries | - |
Other accidents in this area
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 22 May 2025 | Cessna 172N | Murfreesboro, Tennessee, United States | JKG LLC | No injuries | - |
| 25 Aug 2025 | Cessna 170B | Knoxville, Tennessee, United States | - | No injuries | - |
| 17 Jan 2025 | Cessna 182 | Smyrna, Tennessee, United States | - | No injuries | - |
| 10 Jun 2025 | Beechcraft A36 | Murfreesboro, Tennessee, United States | - | Serious injuries | - |
| 12 Jun 2025 | Cirrus SR22 | Hartsville, Tennessee, United States | - | No injuries | - |
| 11 Apr 2025 | Mooney M20F | Reliance, Tennessee, United States | Clear AYR LLC | Fatal | 3 |