Cessna 172N accident near Lyons, Colorado, April 24, 2004
On April 24, 2004 at about 5:40 pm local time, a Cessna 172N, registered N5048E, was substantially damaged in an accident near Lyons, Colorado. It was an instructional flight 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
a loss of engine power due to carburetor icing. Contributing factors were weather conditions conducive to carburetor icing and unsuitable terrain available on which to make a forced landing and the road sign.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 24, 2004 · about 5:40 pm local time
- Place
- Lyons, Colorado · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172N · all 172Ns on the register
- Registration
- N5048E · no longer on the register · serial 17271699
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
According to the flight instructor, they were practicing engine failure procedures (with the use of carburetor heat) when the engine lost power. During the landing roll, the airplane struck a street sign, substantially damaging the airplane. The engine was run by an Airframe and Powerplant mechanic on April 24, 2004. The engine started without hesitation and a carburetor heat check and magneto check were performed with no anomalies. The fuel tanks were reported to be "half full." The temperature was 45 degrees Fahrenheit (F), and the dewpoint was 33 degrees F. According to the Carburetor Icing Chart, the conditions were conducive for "serious icing at cruise power."
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
Flight instructor
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 1,196 hours in all; 178 in this make and model; 39 in the last 90 days; 9 in the last 30 days; 1,114 as pilot in command; 71 on instruments
- Last flight review: September 11, 2003
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: rear
- Injury: no injuries
Dual student
- Flight time: 12 hours in all; 7 in this make and model; 11 in the last 90 days; 5 in the last 30 days
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 8,004 hours
- Last inspection: annual inspection, April 20, 2004; 10 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-H2AD (piston); 0 hours total
The flight
- Departed from: 2V2 Longmont CO at 4:50 pm
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 180° at 8 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 45°F (7°C), dew point 34°F (1°C)
- Altimeter: 29.97 inHg
- Observation at 10:55 pm from FNL, 170 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
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.