Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
38.54N, 173.24W
Friday, December 23, 1988 HST
NTSB Narrative Summary Released at Completion of Accident
UNITED AIRLINES FLT 820 WAS ENRTE FROM NORITA, JAPAN TO SAN FRANCISCO, CA. AT FLT LVL 380 SEVERE CLEAR AIR TURBULENCE WAS ENCOUNTERED. THREE CABIN CREW MEMBERS WERE THROWN TO THE CEILING, TWO OF WHOM WERE INJURED, ONE SUSTAINING A FRACTURED LEG. THE FLT DIVERTED TO HONOLULU AND LANDED WITHOUT INCIDENT. BOTH FLT AND CABIN CREW REPORTED THAT THERE HAD BEEN NO WARNING OF ANY IMPENDING TURBULENCE PRIOR TO ABRUPTLY ENCOUNTERING THE TURBULENCE THAT CAUSED THE INJURIES, AND THAT THE SEAT BELT SIGN WAS TURNED OFF.
NTSB Probable Cause Narrative
AIRCRAFT'S ENCOUNTER WITH UNFORECAST SEVERVE CLEAR TURBULENCE.
Event Information
| Type of Event | Accident |
| Event Date | 12/23/1988 |
| Event Day of the Week | Friday |
| Time of Event | 30 |
| Event Time Zone | Hawaii Standard Time |
| Event City | 38.54N, 173.24W |
| Event State | PACIFIC OCEAN |
| Event Country | -- |
| Zipcode of the event site | 00000 |
| Event Date Year | 1988 |
| Event Date Month | 12 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | |
| Event Location Longitude | |
| Event Location Airport | |
| Event Location Nearest Airport ID | NONE |
| 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 | Pilot |
| Time of the weather observation | 0 |
| Direction of event from weather observation facility (degrees) | 0 |
| Weather Observation Facility ID | |
| Elevation of weather observation facility | 0 |
| Distance of event from weather observation facility (units?) | 0 |
| Time Zone of the weather observation | |
| Lighting Conditions | Dawn |
| Lowest Ceiling Height | 0 |
| Lowest Non-Ceiling Height | 0 |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | None |
| 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) | 10 |
| Dew Point at event time (in degress fahrenheit) | -- |
| Wind Direction (degrees magnetic) | 240 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 0 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Unknown |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 29 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | Unknown |
| METAR weather report | -- |
| Event Highest Injury | Serious |
| On Ground, Fatal Injuries | 0 |
| On Ground, Minor Injuries | 0 |
| On Ground, Serious Injuries | 0 |
| Injury Total Fatal | -- |
| Injury Total Minor | 1 |
| Injury Total None | 220 |
| Injury Total Serious | 1 |
| Injury Total All | 2 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 2363 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Dec 23 1988 12:00AM |
| NTSB Notification Time | 334 |
| Fiche Number and/or location -used to find docket information | 39077 |
| Date of most recent change to record | Dec 13 2000 12:21PM |
| User who most recently changed record | dbo |
| Basic weather conditions | Unknown |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N146UA |
| NTSB Number | LAX89LA068 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 121: Air Carrier |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | -- |
| Damage | None |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | BOEING |
| Aircraft Model | 747SP-21 |
| Aircraft Series Identifier | 747SP-21 |
| Aircraft Serial Number | 21547 |
| Certified Max Gross Weight | 360000 |
| 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 | 331 |
| Number of Engines | 4 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | AAIP |
| Date of Last Inspection | -- |
| Airframe hours since last inspection | -- |
| Airframe Hours | -- |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | BANKER'S TRUST CO. |
| Aircraft Owner Street Address | P.O. BOX 318 |
| Aircraft Owner City | NEW YORK |
| Aircraft Owner State | NY |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | |
| Operator is an individual? | -- |
| Operator Name | UNITED AIRLINES |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | P.O. BOX 66100 |
| Operator City | CHICAGO |
| Operator State | IL |
| Operator Country | |
| Operator Zip code | 60666 |
| Operator Code | UALA |
| 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 | Scheduled |
| Indicates Domestic or International Flight | International |
| Operator carrying Pax/Cargo/Mail | Passenger/Cargo |
| Type of Flying (Per_Bus / Primary) | Unknown |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | NRT |
| Departure City | NORITA |
| Departure State | OF |
| Departure Country | |
| Departure Time | 0 |
| Departure Time Zone | |
| Destination Same as Local Flt | -- |
| Destination Airport Code | SFO |
| Destination City | SAN FRANCISCO |
| Destination State | CA |
| Destination Country | |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jan 2 2001 10:30AM |
| 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 | -- |