UA4778 DenverDEN · 20:25 St LouisSTL · 23:40
UA4778 by United Airlines flies from Denver (DEN) to St Louis (STL) for the Wed, Sep 16 departure.
departs DEN · on schedule
board checked 28m ago · checking again in 45s
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 −19 min · 0 cancelled · 6 operations tracked
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at DEN and STL 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 Denver to St Louis flights today
same route · United AirlinesIf UA4778 is cancelled, these are the other United Airlines nonstop flights from Denver to St Louis on the same day, with scheduled departure times in DEN local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA4778 actually runs
Pro Flight Search has tracked every published board update for UA4778 across the DEN and STL boards: schedule changes, gate pushes and actual clocks. Usually lands ~18 min early. Based on 6 confirmed landings · 4/6 within 15 min of schedule. Pushes back late but makes up time in the air.
The verdict above is that record speaking, so it reflects how UA4778 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: N202SY, N149SY, N121SY, N154SY.
Board clocks recorded as DEN and STL published them.
Planning around UA4778? 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 — UA4778 Denver to St Louis on-time performance, measured from the DEN and STL airport boards.
https://proflightsearch.com/flight/UA4778
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