UA4666 ChicagoORD · 15:40 TucsonTUS · 17:59
UA4666 by United Airlines flies from Chicago (ORD) to Tucson (TUS).
scheduled from ORD
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at ORD and TUS 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 Chicago to Tucson flights today
same route · United AirlinesIf UA4666 is cancelled, these are the other United Airlines nonstop flights from Chicago to Tucson on the same day, with scheduled departure times in ORD local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA4666 actually runs
Pro Flight Search has tracked every published board update for UA4666 across the ORD and TUS boards: schedule changes, gate pushes and actual clocks. Early read — pattern not clear yet. Only 1 completed leg so far: departed +0 min. Not enough to call it.
The verdict above is that record speaking, so it reflects how UA4666 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 ORD and TUS published them.
Planning around UA4666? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — UA4666 Chicago to Tucson on-time performance, measured from the ORD and TUS airport boards.
https://proflightsearch.com/flight/UA4666
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