UA8121 San FranciscoSFO · 10:05 Raleigh/DurhamRDU · 15:46
UA8121 by United Airlines flies from San Francisco (SFO) to Raleigh/Durham (RDU).
Same number through SFO → ORD → RDU
scheduled from SFO
Where the minutes go
last 4 operations · gate push → arrivalThe bar is how late it left the gate; the ring is where it actually arrived. Board clocks, not estimates.
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at SFO and RDU are near their clear-air norm right now, so this reflects the route's recent baseline rather than a weather penalty. For this route and airline, under conditions like today's, over the last 90 days.
Pro Flight Search tracking, 90 days · the weather × delay correlation study → · live weather risk by airport →
When it flies
scheduled departuresEach mark is a scheduled departure at its origin-local time. Today is highlighted.
Other San Francisco to Raleigh/Durham flights today
same route · United AirlinesIf UA8121 is cancelled, these are the other United Airlines nonstop flights from San Francisco to Raleigh/Durham on the same day, with scheduled departure times in SFO local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA8121 actually runs
Pro Flight Search has tracked every published board update for UA8121 across the SFO and RDU boards: schedule changes, gate pushes and actual clocks. Usually lands ~25 min late. Based on 4 confirmed landings · 2/4 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how UA8121 operates rather than what the timetable promises. Numbers refresh as new flights operate.
How this operation is measured
Board log
scheduled → actual, per operationBoard clocks recorded as SFO and RDU published them.
Planning around UA8121? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Pro Flight Search — UA8121 San Francisco to Raleigh/Durham on-time performance, measured from the SFO and RDU airport boards.
https://proflightsearch.com/flight/UA8121
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