UA552 San FranciscoSFO · 21:25 OntarioONT · 22:59
UA552 by United Airlines flies from San Francisco (SFO) to Ontario (ONT).
scheduled from SFO
Where the minutes go
last 6 operations · gate push → arrivalThe bar is how late it left the gate; the ring is where it actually arrived. Board clocks, not estimates.
The last 30 days
arrival outcome per operationmedian arrival +8 min · 0 cancelled · 6 operations tracked
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at SFO and ONT 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 Ontario flights today
same route · United AirlinesIf UA552 is cancelled, these are the other United Airlines nonstop flights from San Francisco to Ontario 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 UA552 actually runs
Pro Flight Search has tracked every published board update for UA552 across the SFO and ONT boards: schedule changes, gate pushes and actual clocks. Usually lands ~11 min late. Based on 6 confirmed landings · 4/6 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how UA552 operates rather than what the timetable promises. Numbers refresh as new flights operate.
How this operation is measured
Board log
scheduled → actual, per operationAircraft
Recent tails: N77573, N68842, N431UA, N66814.
Board clocks recorded as SFO and ONT published them.
Planning around UA552? 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 — UA552 San Francisco to Ontario on-time performance, measured from the SFO and ONT airport boards.
https://proflightsearch.com/flight/UA552
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