Cessna 172N accident near Parker, Colorado, April 25, 1998
On April 25, 1998 at about 7:30 pm local time, a Cessna 172N, registered N6356D, was substantially damaged in an accident near Parker, 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 fractured #1 exhaust valve rocker arm stud, which subsequently resulted in loss of engine power and a forced landing. The lack of suitable terrain in the forced landing area 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
- April 25, 1998 · about 7:30 pm local time
- Place
- Parker, 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
- N6356D · no longer on the register · serial 17272742
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The instructor pilot (CFI) said that after completing a local instructional flight, he and his student entered an extended right base for runway 35R, about 5 miles southeast of the airport. He 'suddenly heard the engine lose a major portion of power.' While performing an emergency check of the instruments, the instructor noted that the engine power had dropped to 1,800 rpm. Realizing they would be unable to glide to the airport due to the loss of engine power, the CFI executed an emergency landing on a field near a golf course. The ground was muddy due to an accumulation of rain and snow from the previous night. After the airplane traveled a short distance, the nose wheel struck a rut, and the airplane nosed over. Examination of the aircraft engine revealed that the #1 (right front) cylinder intake pushrod was bent. After removing the valve cover, a stud that anchored the #1 exhaust valve rocker arm was found to be fractured, and the #1 exhaust valve was in the closed position. There was no damage to the valve lifters or camshaft.
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: 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: 7,300 hours in all; 5,000 in this make and model; 79 in the last 90 days; 29 in the last 30 days; 1,795 as pilot in command; 6,600 on instruments
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 2,121 hours
- Last inspection: 100-hour inspection; 10 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-H2AD (piston); 0 hours total
- Operator: Aspen Air CORP.
The flight
- Departed from: APA Englewood CO at 7:30 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 360° at 10 knots
- Visibility: 50 statute miles
- Sky: broken clouds at 16,000 ft; scat at 8,000 ft
- Temperature: 59°F (15°C), dew point 30°F (-1°C)
- Altimeter: 29.00 inHg
- Observation at 8:35 pm from APA, 5 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.
Other NTSB records under N6356D the same tail number, which may have belonged to a different aircraft at the time
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.