DL4070 OntarioONT · 11:54 SeattleSEA · 14:50
DL4070 by Delta Air Lines flies from Ontario (ONT) to Seattle (SEA) for the Mon, Sep 21 departure.
departs ONT · on schedule
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
Early read, sample still buildingConditions at ONT and SEA 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. This route's tracked sample is still thin — treat these as an early read, not a precise forecast.
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 Ontario to Seattle flights today
same route · Delta Air LinesIf DL4070 is cancelled, these are the other Delta Air Lines nonstop flights from Ontario to Seattle on the same day, with scheduled departure times in ONT local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How DL4070 actually runs
Pro Flight Search has tracked every published board update for DL4070 across the ONT and SEA boards: schedule changes, gate pushes and actual clocks. Usually departs ~33 min late. Based on 4 confirmed departures · 2/4 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how DL4070 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: N243SY, N256SY, N319SY, N302SY.
Board clocks recorded as ONT and SEA published them.
Planning around DL4070? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — DL4070 Ontario to Seattle on-time performance, measured from the ONT and SEA airport boards.
https://proflightsearch.com/flight/DL4070
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