Hughes 369D (500) accident near Provo, Utah, September 30, 1983
On September 30, 1983 at about 5:00 pm local time, a Hughes 369D (500) (helicopter), registered N8693F, was substantially damaged in an accident near Provo, Utah. It was a flight of an unrecorded kind under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. 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
- September 30, 1983 · about 5:00 pm local time
- Place
- Provo, Utah · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Hughes 369D (500) · all 369D (500)s on the register
- Registration
- N8693F · no longer on the register · serial 180252D
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE HELICOPTER WAS ON A TEST FLT TO TRACK & BALANCE THE MAIN ROTOR SYSTEM & TO COMPLETE A 100 HR INSPECTION. PRIOR TO THE FLT, AN OCCASIONAL FLICKER OF THE FUEL FILTER LIGHT WAS NOTED, BUT IT WAS THOUGHT TO BE A WIRING PROBLEM. AFTER TAKING OFF, THE FUEL FILTER LIGHT FLICKERED ON A FEW MORE TIMES, BUT NEVER ILLUMINATED STEADILY. AFTER LESS THAN A MINUTE OF FLYING TIME, THE PLT FELT 2 QUICK 'JERKS' (YAWS). HE START A 180 DEG TURN TO LAND. AFTER 90 DEG OF TURN, THE N2 DECREASED TO 95%, THEN SURGED TO 105%, THEN THE ENG QUIT RUNNING. THE PLT INITIATED AN AUTOROTATION, BUT DURING LANDING ON SOFT, WET TERRAIN, THE HELICOPTER ROCKED FORWARD & THE MAIN ROTOR STRUCK THE TAIL BOOM. AN EXAM OF THE HELICOPTER REVEALED A 'B' NUT ON 1 OF 2 DIFFERENTIAL PRESSURE LINES (CONNECTED TO THE FUEL FILTER DIFFERENTIAL PRESSURE SWITCH) WAS LOOSE. DURING THE EXAM, THE 'B' NUT SEPARATED FROM ITS ATTACH POINT BY A 1/2 TURN USING FINGER PRESSURE.
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
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: helicopter; rotorcraft: helicopter
- Flight time: 10,500 hours in all; 500 in this make and model; 200 in the last 90 days
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 3,183 hours
- Last inspection: 100-hour inspection, September 30, 1983; 0 hours since
- Maximum gross weight: 2,100 lb
- Seats: 2
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 45 statute miles
- Sky: broken clouds at 12,000 ft; scat at 5,500 ft
- Temperature: 57°F (14°C), dew point 48°F (9°C)
- Altimeter: 29.00 inHg
- Observation at 4:46 pm from PVU, 2 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket 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.