UA28 SingaporeSIN · 20:35 San FranciscoSFO · 21:20
UA28 by United Airlines flies from Singapore (SIN) to San Francisco (SFO) for the Sun, Sep 6 departure.
estimated arrival at SFO · local time · ~3h 51m from now
board checked 16m ago · checking again in 45s
Board estimate · gate and arrival times. Off blocks 21:09 · typical taxi-out at SIN ≈ 8.9 min. No receiver coverage over open ocean.
Where the minutes go
last 3 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 SIN and SFO 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 Singapore to San Francisco flights today
same route · United AirlinesIf UA28 is cancelled, these are the other United Airlines nonstop flights from Singapore to San Francisco on the same day, with scheduled departure times in SIN local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA28 actually runs
Pro Flight Search has tracked every published board update for UA28 across the SIN and SFO boards: schedule changes, gate pushes and actual clocks. Early read — pattern not clear yet. Only 1 completed leg so far: left noticeably late (~34 min) but landed a little late (~7 min). Not enough to call it.
The verdict above is that record speaking, so it reflects how UA28 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 SIN and SFO published them.
Planning around UA28? 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 — UA28 Singapore to San Francisco on-time performance, measured from the SIN and SFO airport boards.
https://proflightsearch.com/flight/UA28
.