United Airlines Flight 805
Boeing 747-422 · Incident: in flight encounter with weather en route
From San Francisco International Airport (KSFO) to Hong Kong International Airport (VHHH)
Event
- NTSB case
- ANC01IA022
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Incident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Boeing 747-422
- Aircraft type
- Boeing 747
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N119UA
- Operator
- United Airlines
- Onboard fatalities
- Unknown
- Route
- From San Francisco International Airport (KSFO), San Francisco, CATo Hong Kong International Airport (VHHH), Hong Kong
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air Carrier
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- In flight encounter with weather
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Cause areas
- Weather condition › Turbulence, clear air
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
A Boeing B-747 airplane departed San Francisco for Hong Kong. Prior to departure, no significant meteorological notices or forecasts for turbulence were issued for the area of the Alaska Peninsula, over which the flight would progress. The airplane was initially in radio and data link communications with Oakland ARTCC, then ARINC, and finally with Anchorage ARTCC. A PIREP at 1432 for moderate turbulence, and an Urgent PIREP at 1600 of severe turbulence, were recorded in the area of incident by Anchorage ARTCC. As the flight entered the Alaska ARTCC area, a delay in establishing communications with the airplane also delayed the transmission of the urgent PIREP concerning turbulence in the area of the flight. The crew noticed rolling clouds ahead of the airplane and advised the cabin flight attendants to be seated. At 1620, while in cruise flight at 31,000 feet, the airplane encountered moderate to severe turbulence. About 5 seconds after the notification to sit down, three cabin attendants were thrown to the floor of the airplane. The captain diverted the flight to Anchorage. Upon arrival at Anchorage, a belly mounted fuselage panel enclosing an air conditioning unit, was missing. Airplanes conducting oceanic flights are equipped with ACARS, over which flight crews can receive ATC clearances and weather data utilizing controller/pilot data link communications (CPDLC). The Anchorage ARTCC was not utilizing CPDLC because their software is not user friendly, requires substantial controller input for free text messaging, and is not as fast as voice communications. Hazardous inflight weather advisories are reviewed by each center weather coordinator, in conjunction with the National Weather Service for dissemination to pilots. The FAA does not a direct mechanism to alert air crews of significant weather in one sector, occurring in another sector, nor does the FAA have a mechanism to coordinate CPDLC data from an ARTCC sector to ARINC. A SIGMET for occasional turbulence was issued by the National Weather Service at 1619.
Probable cause
An encounter with severe turbulence while in cruise flight. Factors in the incident were a delay in notification of the turbulence, and the lack of controller/pilot data link communications in the Anchorage ARTCC area.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC01IA022
- Event ID
- 20010110X00085
- Case number
- ANC01IA022
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (5)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: aa8d006a4a655a686cf2c5ff19b088c7d1109afca37a9e533fd69d781a59ac3a; retrieved 2026-09-18T16:19:09.386Z.
- The NTSB's operator name is blank for N119UA; the operator shown is the name the NTSB's other records give its FAA operator code, UALA.