Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Bishop, California 93514
Saturday, July 17, 2004 8:30 PDT
NTSB Narrative Summary Released at Completion of Accident
The airplane impacted a glacier at 12,270 feet mean sea level (msl) after the pilot attempted to reverse course out of a bowl-shaped valley in the Sierra Nevada mountain range. Ground scar analysis and crush angle measurements on the airplane disclosed that it descended in a near vertical nose down attitude to impact on the glacier. The valley was surrounded by higher peaks and ridges, and the accident site was about 1.3 nautical miles southeast of the direct point-to-point course between the departure and destination airports. At the northeast end of the valley, an opening led down slope through lower mountains and valleys to the airplane's departure point. Satellite imagery indicated that a low layer of stratiform clouds was present over the mountains during the time period following the airplane's departure. The accident site was under the northern edge of these low clouds. Based on the cloud radiative temperatures observed on the satellite imagery, the cloud tops were 16,000 feet mean sea level and the cloud bases were between 10,000 and 14,000 feet msl. The bowl-shaped valley was about 2,450 feet in diameter near the tops of the higher peaks and about 1,200 feet at the elevation of the wreckage. The bank angle required for a turn radius of 1,225 feet at an airspeed of 104 knots (best rate of climb) is 40 degrees. At 156 knots (maneuvering airspeed), the airplane's bank angle would have been 65 degrees. Using a radius of 637.5 feet (the accident site elevation diameter) and 104 knots, the bank angle would have had to have been at least 60 degrees to complete the turn. At 156 knots, the required bank angle would have been about 75 degrees. According to stall speed versus angle of bank data for the airplane, the stall speed would be 85 knots at 40 degrees of bank varying to 105 knots indicated air speed at 60 degrees of bank. No evidence of mechanical malfunction or failure was found during a post accident examination of the airplane and engines. Internal signatures in the propeller hubs disclosed that both engines were producing power symmetrically at the time of impact.
NTSB Probable Cause Narrative
the pilot's continued VFR flight into marginal weather conditions with lowering ceilings in a box canyon in mountainous terrain, and his subsequent inability to maintain an adequate airspeed while maneuvering to reverse direction, which led to an accelerated stall and spin.
Event Information
| Type of Event | Accident |
| Event Date | 7/17/2004 |
| Event Day of the Week | Saturday |
| Time of Event | 830 |
| Event Time Zone | Pacific Daylight Time |
| Event City | Bishop |
| Event State | CALIFORNIA |
| Event Country | -- |
| Zipcode of the event site | 93514 |
| Event Date Year | 2004 |
| Event Date Month | 7 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 370818N |
| Event Location Longitude | 1183834W |
| 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 | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 756 Pacific Daylight Time |
| Direction of event from weather observation facility (degrees) | 27 |
| Weather Observation Facility ID | BIH |
| Elevation of weather observation facility | 4120 |
| Distance of event from weather observation facility (units?) | 18 |
| Time Zone of the weather observation | PDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 23 |
| Dew Point at event time (in degress fahrenheit) | 12 |
| Wind Direction (degrees magnetic) | 330 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 4 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.06 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Fatal |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| 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) | 18494 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Jul 18 2004 12:00AM |
| NTSB Notification Time | 700 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Oct 27 2005 6:51AM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | WP-RNO-FSDO |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N807Q |
| NTSB Number | LAX04FA271 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Destroyed |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Beech |
| Aircraft Model | 58 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | TH-823 |
| Certified Max Gross Weight | 5400 |
| 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 | 6 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | May 12 2004 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 2174.7 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | Yes |
| ELT Type | -- |
| Aircraft Owner Name | Darrell Tunnell Company |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Visalia |
| Aircraft Owner State | CA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 93191 |
| Operator is an individual? | No |
| Operator Name | Anthony Sario |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | -- |
| Operator City | Visalia |
| Operator State | CA |
| Operator Country | USA |
| Operator Zip code | 93291 |
| 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) | Personal |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | BIH |
| Departure City | Bishop |
| Departure State | CA |
| Departure Country | USA |
| Departure Time | 815 |
| Departure Time Zone | PDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | PRB |
| Destination City | Paso Robles |
| Destination State | CA |
| Destination Country | USA |
| Specific Phase of Flight | Maneuvering - turn to reverse direction |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Jul 18 2005 4:49PM |
| User who most recently changed record | COOS |
| Since inspection or accident | Last Inspection |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |