Enstrom TH-28 accident near Leadville, Colorado, February 29, 1992
On February 29, 1992 at about 5:22 pm local time, a Enstrom TH-28 (helicopter), registered N8631E, was substantially damaged in an accident near Leadville, Colorado (Lake County airport). It was a flight of an unrecorded kind under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE PILOT MISJUDGING THE DESCENT RATE AND CONSEQUENTLY DELAYING THE FLARE. A FACTOR WAS: DOWNDRAFT.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 29, 1992 · about 5:22 pm local time
- Place
- Leadville, Colorado · Lake County · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Enstrom TH-28
- Registration
- N8631E · registry record · serial 3003
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THIS WAS ONE OF A SERIES OF EXPERIMENTAL TEST FLIGHTS LEADING TOWARDS FAA CERTIFICATION OF THE MODIFIED HELICOPTER. DATA POINTS FOR THE HEIGHT VELOCITY CURVE HAD BEEN COLLECTED AND THE PILOT WAS ATTEMPTING TO CONFIRM THEIR ACCURACY. AT 46 KNOTS AND 400 FEET AGL, THE PILOT MADE AN INTENTIONAL AUTOROTATION. HE SAID THE SINK RATE WAS HIGHER THAN PREVIOUSLY NOTED, AND HEAVY ROTOR BLADE STALL MADE THE FLARE INEFFECTIVE. THE PILOT SAID A DOWNDRAFT MAY HAVE PRECIPITATED THE ACCIDENT.
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: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: helicopter; instrument: airplane; instrument: helicopter; rotorcraft: balloon; rotorcraft: helicopter
- Flight time: 6,479 hours in all; 889 in this make and model; 97 in the last 90 days; 50 in the last 30 days; 5,383 as pilot in command; 756 on instruments
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 575 hours
- Last inspection: 100-hour inspection, January 20, 1992; 36 hours since
- Maximum gross weight: 2,750 lb
- Seats: 3
- Landing gear: fixed
- Engine: Allison 250-C20W (turboshaft); 0 hours total
- Operator: Enstrom Helicopter Corporation
The flight
- Flight plan: none
- Runway 34, 5,300 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 340° at 5 knots
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 39°F (4°C), dew point 21°F (-6°C)
- Altimeter: 30.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.