Individually Owned: 150,657
Corporate Owned: 137,281
Mariposa-Yosemite Airport
Aircraft Accident/Incident Report
Mariposa, California 93653
Tuesady, January 24, 2006 9:51 PST
NTSB Narrative Summary Released at Completion of Accident
The aircraft collided with multiple obstacles during a forced landing in rough terrain following a catastrophic engine failure. While en route about 6,000 feet mean sea level, one cylinder in the engine indicated a loss of exhaust gas and cylinder head temperature. Thereafter, an increasingly strong vibration was felt, oil dispersed onto the front windscreen, and all engine power was lost. During the landing flare, the airplane impacted an oak tree, a fence, and a rock outcrop. The engine was found separated from the airplane's firewall. Also, the number 6 cylinder was observed broken from the engine case. The engine was torn down and the case was opened. The evidence of the torque values found on all the engine through-bolts, combined with the fretting signature at the base of the number 6 cylinder, and the oil residue at the union of the case halves, indicates that when the cylinders were installed on the engine their respective bolts were inadequately torqued. During an interview with the mechanic who had replaced the 6 cylinders on the engine, he reported that he followed the instructions in TCM's maintenance manual when he had replaced the cylinders in May 2005. He said he torqued the nuts on the cylinders to about 500 inch pounds. According to TCM's maintenance manual, 1989 edition, the required torque for the through-bolts was 690 to 710 inch pounds. By 1996, TCM had revised its manual by issuance of service bulletin 96-7. In that bulletin the required torque was increased to between 790 to 810 inch pounds.
NTSB Probable Cause Narrative
The failure of the maintenance personnel to follow the procedures in the TCM maintenance manual and adequately torque the engine through-bolts, which led to the separation of the No. 6 cylinder and the catastrophic failure of the engine.
Event Information
| Type of Event | Accident |
| Event Date | 1/24/2006 |
| Event Day of the Week | Tuesday |
| Time of Event | 951 |
| Event Time Zone | Pacific Standard Time |
| Event City | Mariposa |
| Event State | CALIFORNIA |
| Event Country | -- |
| Zipcode of the event site | 93653 |
| Event Date Year | 2006 |
| Event Date Month | 1 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 371944N |
| Event Location Longitude | 1200328W |
| Event Location Airport | Mariposa-Yosemite |
| Event Location Nearest Airport ID | MPI |
| Indicates whether the acc/inc occurred off or on an airport | Off Airport/Airstrip |
| Distance from airport in statute miles | 11 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 2254 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 953 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | 245 |
| Weather Observation Facility ID | MCE |
| Elevation of weather observation facility | 156 |
| Distance of event from weather observation facility (units?) | 20 |
| Time Zone of the weather observation | PST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 100 |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | -- |
| Sky Condition for Lowest Ceiling | Indefinite (V V) |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 0.25 |
| Air Temperature at event time (in degrees celsius) | 4 |
| Dew Point at event time (in degress fahrenheit) | 4 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | -- |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | Calm |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.13 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Minor |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | 1 |
| Injury Total Serious | -- |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 22062 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Jan 24 2006 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Aug 30 2007 12:18PM |
| User who most recently changed record | NTSB\lema |
| Basic weather conditions | Instrument Meteorological Cond |
| FAA District Office | Fresno, CA |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N4791C |
| NTSB Number | LAX06LA094 |
| Missing Aircraft Indicator | -- |
| 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 | T210N |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 21063627 |
| Certified Max Gross Weight | 3800 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 6 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Feb 1 2005 12:00AM |
| Airframe hours since last inspection | 208 |
| Airframe Hours | 4046 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | Yes |
| ELT Type | -- |
| Aircraft Owner Name | Representations, LLC. |
| Aircraft Owner Street Address | 3681 Sagunto St. #105 |
| Aircraft Owner City | Santa Ynez |
| Aircraft Owner State | CA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 93460 |
| Operator is an individual? | No |
| Operator Name | Ross Rankin |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | -- |
| Operator State | -- |
| Operator Country | -- |
| Operator Zip code | -- |
| Operator Code | -- |
| Owner has at least one certificate | None |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | -- |
| 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) | Business |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | VIS |
| Departure City | Visalia |
| Departure State | CA |
| Departure Country | USA |
| Departure Time | 912 |
| Departure Time Zone | PST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | MPI |
| Destination City | Mariposa |
| Destination State | CA |
| Destination Country | USA |
| Specific Phase of Flight | Landing - flare/touchdown |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Aug 6 2007 5:51PM |
| User who most recently changed record | COOS |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |