UA1721 San FranciscoSFO · 08:16 Kailua-KonaKOA · 10:49
UA1721 by United Airlines flies from San Francisco (SFO) to Kailua-Kona (KOA) for the Sun, Sep 13 departure.
en route from SFO to KOA
board checked 11m ago · checking again in 45s
Board estimate · gate and arrival times. Off blocks 08:10 · typical taxi-out at SFO ≈ 13.2 min. No receiver coverage over open ocean.
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 +7 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 KOA 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 Kailua-Kona flights today
same route · United AirlinesIf UA1721 is cancelled, these are the other United Airlines nonstop flights from San Francisco to Kailua-Kona 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 UA1721 actually runs
Pro Flight Search has tracked every published board update for UA1721 across the SFO and KOA boards: schedule changes, gate pushes and actual clocks. Usually departs ~5 min early. Based on 6 confirmed departures · 6/6 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how UA1721 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: N27520, N37540, N17459, N17418.
Board clocks recorded as SFO and KOA published them.
Planning around UA1721? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — UA1721 San Francisco to Kailua-Kona on-time performance, measured from the SFO and KOA airport boards.
https://proflightsearch.com/flight/UA1721
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