Individually Owned: 150,657
Corporate Owned: 137,281
Ontario International Airport
Aircraft Accident/Incident Report
Ontario, California 91761
Tuesady, December 25, 2007 9:18 PST
NTSB Narrative Summary Released at Completion of Accident
Two flight attendants were seriously injured when the airplane encountered severe turbulence while descending for landing. The turbulence was likely the result of strong easterly winds interacting with the rough terrain in the area (mechanical turbulence). The flight data recorder data indicates that the airplane experienced a vertical acceleration of +0.4 G to +1.9 G, or 1.5 G total change, which corresponds to severe turbulence. The National Weather Service forecast the severe turbulence in Significant Meteorological Advisory (SIGMET) Victor 2, which was issued before the flight departed. The weather company that provides weather information to the operator did not forecast severe turbulence for the area. The content of SIGMET Victor 2 was available to the flight's dispatcher. However, this information was not provided to the flight crew. The two flight attendants who sustained injuries were both standing, completing final cabin duties in preparation for landing, and were knocked to the floor during the turbulence encounter.
NTSB Probable Cause Narrative
The lack of turbulence forecasts available to the flight crew, which resulted in the flight attendants not being seated when the flight encountered severe terrain-induced turbulence. Contributing to the accident were the terrain-induced turbulence, the failure of the company that provided the flight's weather briefing to forecast severe turbulence, and the failure of the dispatcher to provide the National Weather Service severe turbulence forecast to the flight.
Event Information
| Type of Event | Accident |
| Event Date | 12/25/2007 |
| Event Day of the Week | Tuesday |
| Time of Event | 918 |
| Event Time Zone | Pacific Standard Time |
| Event City | Ontario |
| Event State | CALIFORNIA |
| Event Country | -- |
| Zipcode of the event site | 91761 |
| Event Date Year | 2007 |
| Event Date Month | 12 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 340322N |
| Event Location Longitude | 1173604W |
| Event Location Airport | Ontario International |
| Event Location Nearest Airport ID | ONT |
| 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 | 944 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 853 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | ONT |
| Elevation of weather observation facility | 944 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | PST |
| 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) | 16 |
| Dew Point at event time (in degress fahrenheit) | -20 |
| Wind Direction (degrees magnetic) | 50 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 23 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Gusting |
| Wind Gust (knots) | 37 |
| Altimeter Setting at event time (in. Hg) | 30.16 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Serious |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 112 |
| Injury Total Serious | 2 |
| Injury Total All | 2 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 24891 |
| NTSB Notification Source | FAA ROC |
| NTSB Notification Date | Dec 25 2007 12:00AM |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Jan 6 2009 1:59PM |
| User who most recently changed record | stam |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Van Nuys, CA |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N943AS |
| NTSB Number | SEA08LA050 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | Yes |
| Damage | None |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | MCDONNELL DOUGLAS |
| Aircraft Model | DC-9-83 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 53018 |
| Certified Max Gross Weight | 160000 |
| Aircraft Category | Airplane |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | 3 |
| Cabin Crew Seats | 4 |
| Passenger Seats | 140 |
| Total number of seats on the aircraft | 147 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Continuous Airworthiness |
| Date of Last Inspection | Aug 17 2007 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 55606 |
| ELT Installed | No |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | Wells Fargo Bank Northwest |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Salt Lake City |
| Aircraft Owner State | UT |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 84111 |
| Operator is an individual? | No |
| Operator Name | Alaska Airlines, Inc. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | -- |
| Operator City | Seattle |
| Operator State | WA |
| Operator Country | USA |
| Operator Zip code | 98188 |
| Operator Code | ASAA |
| Owner has at least one certificate | Yes - certificate holder |
| Other Operator of large aircraft? | No |
| Certified for Part 133 or 137 Operation | -- |
| Operator Certificate Number | -- |
| Indicates whether an air carrier operation was scheduled or not | Scheduled |
| Indicates Domestic or International Flight | Domestic |
| Operator carrying Pax/Cargo/Mail | Passenger Only |
| Type of Flying (Per_Bus / Primary) | -- |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | SEA |
| Departure City | Seattle |
| Departure State | WA |
| Departure Country | USA |
| Departure Time | 703 |
| Departure Time Zone | PST |
| Destination Same as Local Flt | crash at destination city |
| Destination Airport Code | ONT |
| Destination City | Ontario |
| Destination State | CA |
| Destination Country | USA |
| Specific Phase of Flight | Descent |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jan 6 2009 1:52PM |
| User who most recently changed record | stam |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | N/A |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |