Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Parker, Colorado 80134
Saturday, April 25, 1998 13:30 MDT
NTSB Narrative Summary Released at Completion of Accident
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.
NTSB Probable Cause Narrative
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.
Event Information
| Type of Event | Accident |
| Event Date | 4/25/1998 |
| Event Day of the Week | Saturday |
| Time of Event | 1330 |
| Event Time Zone | Mountain Daylight Time |
| Event City | PARKER |
| Event State | COLORADO |
| Event Country | -- |
| Zipcode of the event site | 80134 |
| Event Date Year | 1998 |
| Event Date Month | 4 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | |
| Event Location Longitude | |
| Event Location Airport | |
| Event Location Nearest Airport ID | |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1335 Mountain Standard Time |
| Direction of event from weather observation facility (degrees) | 295 |
| Weather Observation Facility ID | APA |
| Elevation of weather observation facility | 5883 |
| Distance of event from weather observation facility (units?) | 5 |
| Time Zone of the weather observation | MST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 16000 |
| Lowest Non-Ceiling Height | 8000 |
| Sky/Lowest/Cloud Conditions | Scattered |
| Sky Condition for Lowest Ceiling | Broken |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 50 |
| Air Temperature at event time (in degrees celsius) | 15 |
| Dew Point at event time (in degress fahrenheit) | -1 |
| Wind Direction (degrees magnetic) | 360 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 10 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 29 |
| Density Altitude (feet) | 7426 |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 109 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Apr 25 1998 12:00AM |
| NTSB Notification Time | 1353 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Dec 11 2000 11:08AM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N6356D |
| NTSB Number | FTW98LA198 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Cessna |
| Aircraft Model | 172N |
| Aircraft Series Identifier | 172N |
| Aircraft Serial Number | 17272742 |
| Certified Max Gross Weight | 2300 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | U.S. Registered/U.S. Soil |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 4 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | -- |
| Airframe hours since last inspection | 10 |
| Airframe Hours | 2121 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | 757GC CORPORATION |
| Aircraft Owner Street Address | 19 E. SKYE LA. |
| Aircraft Owner City | HGHLNDS RNCH |
| Aircraft Owner State | CO |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 80126 |
| Operator is an individual? | -- |
| Operator Name | ASPEN AIR CORP. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 12340 CONTROL TOWER RD. |
| Operator City | ENGLEWOOD |
| Operator State | CO |
| Operator Country | |
| Operator Zip code | 80112 |
| Operator Code | |
| Owner has at least one certificate | None |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | Unknown |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | -- |
| Indicates Domestic or International Flight | -- |
| Operator carrying Pax/Cargo/Mail | -- |
| Type of Flying (Per_Bus / Primary) | Instructional |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | APA |
| Departure City | ENGLEWOOD |
| Departure State | CO |
| Departure Country | |
| Departure Time | 1230 |
| Departure Time Zone | MST |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | |
| Destination City | |
| Destination State | |
| Destination Country | |
| Specific Phase of Flight | Emergency landing |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jan 2 2001 10:34AM |
| User who most recently changed record | dbo |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | 0 |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |