Cessna 414-8 accident near Cheyenne, Wyoming, October 20, 1984
On October 20, 1984 at about 7:38 pm local time, a Cessna 414-8, registered N1597T, was destroyed in an accident near Cheyenne, Wyoming. It was a business flight under general aviation rules (Part 91). 3 people were seriously injured; 1 other was unhurt. The weather was instrument conditions (cloud, fog or low visibility).
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
- October 20, 1984 · about 7:38 pm local time
- Place
- Cheyenne, Wyoming · map
- Type
- Accident
- Injuries
- 3 people were seriously injured; 1 other was unhurt.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Cessna 414-8 · all 414-8s on the register
- Registration
- N1597T · no longer on the register · serial 414-0377
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE ACFT DEPARTED THE AIRPORT IN IFR CONDITIONS (SNOWING) & WAS OBSERVED STAGGERING INTO THE AIR. SHORTLY AFTER TAKEOFF THE ACFT STRUCK POWER LINES & CRASHED INTO HOMES IN A RESIDENTIAL AREA. INVESTIGATION REVEALED THAT THE ACFT HAD ACCUMULATED ICE & IN ADDITION WAS OVER CERTIFIED MAX GROSS WEIGHT. THERE WAS NO EVIDENCE OF AIRFRAME, FLT CONTROL OR ENGINE FAILURE/MALFUNCTION PRIOR TO IMPACT WITH THE POWER LINES.
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: private
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 13,200 hours in all; 12,800 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 18,035 hours
- Last inspection: annual inspection, July 9, 1983; 0 hours since
- Maximum gross weight: 6,825 lb
- Seats: 7
- Landing gear: retractable
- Engine: Lycoming IO-720-B1BD (piston); 0 hours total
- Fire on the ground
The flight
- Departed from: CYS Cheyenne WY
- Destination: SLC Salt Lake City UT
- Flight plan: IFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 020° at 8 knots
- Visibility: 5 statute miles
- Sky: overcast at 800 ft; not recorded at 800 ft
- Temperature: 23°F (-5°C), dew point 21°F (-6°C)
- Altimeter: 29.00 inHg
- Observation at 7:44 pm from CYS, 1 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 2 | 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.