Beech F33A accident near Sterling, Colorado, March 10, 1991
On March 10, 1991 at about 6:00 pm local time, a Beech F33A, registered N4179S, was destroyed in an accident near Sterling, Colorado. It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
POOR JUDGEMENT OF THE PILOT AND HIS MISJUDGEMENT OF ALTITUDE WHILE BUZZING OVER GLASSY WATER. HIS LACK OF VISUAL QUES TO JUDGE ALTITUDE OVER GLASSY WATER WAS A RELATED FACTOR.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 10, 1991 · about 6:00 pm local time
- Place
- Sterling, Colorado · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Beech F33A · all F33As on the register
- Registration
- N4179S · no longer on the register · serial CE-572
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
A YOUNG PILOT AND HIS PASSENGER FRIEND WERE OBSERVED `BUZZING' THE STERLING, COLORADO, WATER RESERVOIR. THE WITNESSES STATED THAT THE AIRCRAFT WAS SKIMMING THE GLASSY SURFACE OF THE WATER WHEN IT STRUCK THE WATER, PITCHED UP ABRUPTLY, THEN NOSED DOWN UNTIL IT IMPACTED THE WATER AND SANK.
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: airplane
- Flight time: 297 hours in all; 5 in the last 90 days
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 3,400 lb
- Seats: 5
- Landing gear: retractable
- Engine: Continental IO-520-BA (piston); 0 hours total
The flight
- Departed from: AKO Akron CO at 5:45 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 15 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
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.