Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Eagle Mountain, California 92241
Thursday, March 11, 1993 20:20 PST
NTSB Narrative Summary Released at Completion of Accident
A CESSNA 421 CRASHED AFTER AN INFLIGHT BREAKUP. INVESTIGATION DISCLOSED THAT THE LEFT OUTBOARD PORTION OF THE ELEVATOR ASSEMBLY (INCLUDING THE BALANCE WEIGHT) SEPARATED FIRST, RESULTING IN EMPENNAGE FLUTTER & SUBSEQUENT IN-FLIGHT BREAKUP OF THE EMPENNAGE. THE LEFT ELEVATOR OUTBOARD HINGE & SUPPORT STRUCTURE EXHIBITED EVIDENCE OF HINGE OVERTRAVEL. THE LEFT HORIZONTAL STABILIZER FRONT SPAR HAD FAILED DOWNWARD; RIVETS THAT ATTACHED THE LEFT OUTBOARD HINGE TO THE REAR SPAR OF THE LEFT STABILIZER HAD SHEARED; AND THE LEFT ELEVATOR CENTER HINGE HAD BEEN PULLED OFF THE REAR SPAR. ABOUT 100 FLIGHT HOURS BEFORE THE ACCIDENT, MAINTENANCE WAS PERFORMED TO REPAIR THE LEFT ELEVATOR BALANCE WEIGHT (WHICH WAS LOOSE) & TO REPAIR A DAMAGED STIFFENER IN THE CENTER STRUCTURE OF THE HORIZONTAL STABILIZER. HOWEVER, WHEN EXAMINED AFTER THE ACCIDENT, THE BALANCE WEIGHT WAS TIGHT & THE REPAIR TO THE STIFFENER WAS INTACT.
NTSB Probable Cause Narrative
FAILURE OF THE LEFT ELEVATOR FOR UNDETERMINED REASON(S), WHICH RESULTED IN FLUTTER AND FAILURE OF THE EMPENNAGE, AND SUBSEQUENT UNCONTROLLED COLLISION WITH THE TERRAIN.
Event Information
| Type of Event | Accident |
| Event Date | 3/11/1993 |
| Event Day of the Week | Thursday |
| Time of Event | 2020 |
| Event Time Zone | Pacific Standard Time |
| Event City | EAGLE MOUNTAIN |
| Event State | CALIFORNIA |
| Event Country | -- |
| Zipcode of the event site | 92241 |
| Event Date Year | 1993 |
| Event Date Month | 3 |
| 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 | 0 |
| Degrees magnetic from airport | 0 |
| Airport Elevation | -- |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 2052 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | 232 |
| Weather Observation Facility ID | TRM |
| Elevation of weather observation facility | 117 |
| Distance of event from weather observation facility (units?) | 25 |
| Time Zone of the weather observation | PST |
| Lighting Conditions | Night/Dark |
| Lowest Ceiling Height | 0 |
| Lowest Non-Ceiling Height | 20000 |
| Sky/Lowest/Cloud Conditions | Thin Broken |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | 0 |
| Visibility Runway Visual Value (Statute Miles) | 0 |
| Visibility (Statute Miles) | 20 |
| Air Temperature at event time (in degrees celsius) | 14 |
| Dew Point at event time (in degress fahrenheit) | 3 |
| Wind Direction (degrees magnetic) | 300 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 5 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 30 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | Fatal |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | 3 |
| Injury Total Minor | -- |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 3 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 968 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Mar 12 1993 12:00AM |
| NTSB Notification Time | 1405 |
| Fiche Number and/or location -used to find docket information | 51233 |
| Date of most recent change to record | Dec 11 2000 1:11PM |
| User who most recently changed record | dbo |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N2656N |
| NTSB Number | LAX93FA149 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | Company VFR |
| Flight plan Was Activated? | -- |
| Damage | Destroyed |
| Aircraft Fire | Ground |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | CESSNA |
| Aircraft Model | 421C |
| Aircraft Series Identifier | 421C |
| Aircraft Serial Number | 714 |
| Certified Max Gross Weight | 7450 |
| 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 | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | AAIP |
| Date of Last Inspection | Mar 3 1993 12:00AM |
| Airframe hours since last inspection | 11 |
| Airframe Hours | 4869 |
| ELT Installed | Yes |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | CRITICAL AIR MEDICINE |
| Aircraft Owner Street Address | 4141 KEARNY VILLA ROAD |
| Aircraft Owner City | SAN DIEGO |
| Aircraft Owner State | CA |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 92123 |
| Operator is an individual? | -- |
| Operator Name | |
| Operator Same as Owner? | Yes |
| 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 | IBUA |
| Owner has at least one certificate | Yes - certificate holder |
| 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) | Positioning |
| Second Pilot on Board | Unknown |
| Departure Point Same as Event | No |
| Departure Airport Code | UDD |
| Departure City | BERMUDA DUNES |
| Departure State | CA |
| Departure Country | |
| Departure Time | 2000 |
| Departure Time Zone | PST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | P20 |
| Destination City | PARKER |
| Destination State | AZ |
| Destination Country | |
| Specific Phase of Flight | Descent |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Dec 11 2000 1:11PM |
| 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 | -- |