Hughes 369D accident near West Alton, Missouri, August 7, 2025
On August 7, 2025 at about 3:59 pm local time, a 1976 Hughes 369D (helicopter), registered N173AL, was destroyed in an accident during maneuvering (hover) near West Alton, Missouri (N/A airport). It was an other work-use flight under external-load helicopter rules (Part 133). 2 people were killed. 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 October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 7, 2025 · about 3:59 pm local time
- Place
- West Alton, Missouri · N/A · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Hughes 369D, built 1976 · all 369Ds on the register
- Registration
- N173AL · registry record · serial 1160020D
- Damage
- Destroyed
- Flight
- Other work-use flight · external-load helicopter rules (Part 133)
The NTSB's narrative preliminary · quoted from the NTSB record
On August 7, 2025, about 1059 central daylight time, a Hughes (MD Helicopters) 369D helicopter, N173AL, was destroyed when it was involved in an accident near West Alton, Missouri. The pilot and crewmember were fatally injured. The helicopter was operated as a Title 14 Code of Federal Regulations Part 133 external load flight. According to the available Automatic Dependent Surveillance – Broadcast (ADS-B) data for the helicopter, the pilot departed from the north bank of the river about 1025. He appeared to make three trips to the powerline support tower on the south bank of the river and then return to the original position on the north bank. The final ADS-B data point was recorded at 1035. No further ADS-B data was recorded. A witness located on the tow vessel reported that the helicopter pilot and lineman appeared to be attempting to attach a safety marker (orange ball) to one of the power lines. The lineman appeared to be standing on the left skid, wearing a safety harness. On the second attempt, as the pilot brought the helicopter closer to the power lines at which time the tail of the helicopter struck the line. From the witness’ vantage point, it appeared that the tailboom partially separated from the airframe with a portion of it “dangling.” The helicopter then pivoted, and the cockpit hit the line which caused sparks similar to when an electrical transformer fails. The helicopter then fell onto the barge deck and a postimpact fire ensued. The witness did not recall seeing the helicopter on fire during flight, only the sparks when the fuselage struck the line. The crew moved the tow vessel alongside the barge and used its pilothouse fire station to extinguish the fire. A subsequent inspection of the barge did not reveal any structural damage or any release of the barge contents. The helicopter main wreckage consisted of the fuselage, engine, main rotor transmission, main rotor hub, and forward portion of the tail boom (fragmented into two sections). One main rotor blade was located about 150 ft from the main wreckage. A 7-foot segment of a second main rotor blade was located about 176 ft from the main wreckage. Finally, a main rotor blade tip, about 6-inches in length, was located about 26 ft from the main wreckage. The remaining main rotor blades and the aft portion of the tail boom, including the tail rotor and horizontal stabilizer, were not present with the wreckage and presumed to have landed in the river. The video data recorder onboard the tow vessel was retained for examination and download. A search of the river bottom in the vicinity of the accident site using side-scan sonar equipment is planned. The helicopter wreckage was retained for possible further examination. Figure 1 – Accident Site with Powerline Support Tower Figure 2 – Main Wreckage on Barge Deck Figure 3 – Main Wreckage on Barge Deck
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 with terrain or object (not controlled flight into terrain) during maneuvering (hover)
- Miscellaneous/other during maneuvering (hover) defining event
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The aircraft
- Seats: 4
- Landing gear: fixed
- Fire on the ground
The flight
- Departed from: PVT Alton IL at 3:55 pm
- Destination: PVT Alton IL
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: at 5 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 86°F (30°C), dew point 70°F (21°C)
- Altimeter: 30.19 inHg
- Observation at 10:50 am from KALN, 5 miles away
Weather report (METAR): METAR KALN 071550Z VRB05KT 10SM CLR 30/21 A3019
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
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.
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.
