- Date
- December 23, 1988, 00:30 local (10:30 UTC)
- Place
- Midway Islands (Pacific Ocean)
- Injuries
- 1 serious, 1 minor, 220 uninjured
- Damage
- No damage
- Phase of flight
- Enroute
- Aircraft
- N146UABoeing 747SP-21
- Weather
- Dawn
- Status
- Completed · report July 9, 1990
- Report
- Approved by Office Director
- FAA report
- 19881223056109I
- Case key
- 26312
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
Aircraft's encounter with unforecast severve clear turbulence.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
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.
Aircraft
- Registration
- N146UA
- Reported as
- Boeing 747SP-21
- Category
- Airplane
- Serial number
- 21547
- Engine
- P&W JT-9D, 40,000 lbs thrust, turbo fan
- Damage
- No damage
- Flight
- Part 121
- Operator
- United Airlines
- Registered owner
- Banker'S Trust Co.
- Airworthiness certificate
- Standard, Transport
- Departed
- NRT · Norita, OF
- Destination
- SFO · San Francisco, CA
- Flight plan
- IFR
- Airport
- NONE
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 60
- Certificate
- Airline transport
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 22,735 total · 810 in this make and model · 40 in the last 90 days · 13 in the last 24 hours
Weather
- Conditions
- Dawn
- Visibility
- 50 statute miles
- Lowest ceiling
- None
- Temperature
- 50 °F
- Altimeter
- 29.00 inHg
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.