DL400 San FranciscoSFO · 07:10 BostonBOS · 15:57
DL400 by Delta Air Lines flies from San Francisco (SFO) to Boston (BOS) for the Tue, Sep 8 departure.
estimated arrival at BOS · local time · ~60 min from now
position updated 3m ago · checking again in 90s
Live position · flown path, last 4h 8m
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 BOS 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 Boston flights today
same route · Delta Air LinesIf DL400 is cancelled, these are the other Delta Air Lines nonstop flights from San Francisco to Boston 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 DL400 actually runs
Pro Flight Search has tracked every published board update for DL400 across the SFO and BOS boards: schedule changes, gate pushes and actual clocks. Early read — pattern not clear yet. Only 2 completed legs so far: landed -11 min. Not enough to call it.
The verdict above is that record speaking, so it reflects how DL400 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 BOS published them.
Planning around DL400? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — DL400 San Francisco to Boston on-time performance, measured from the SFO and BOS airport boards.
https://proflightsearch.com/flight/DL400
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