UA4520 New YorkEWR LouisvilleSDF
UA4520 by United Airlines flies from New York (EWR) to Louisville (SDF).
scheduled from EWR
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at EWR and SDF 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 New York to Louisville flights today
same route · United AirlinesIf UA4520 is cancelled, these are the other United Airlines nonstop flights from New York to Louisville on the same day, with scheduled departure times in EWR local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA4520 actually runs
Pro Flight Search has tracked every published board update for UA4520 across the EWR and SDF boards: schedule changes, gate pushes and actual clocks. Combined risk score: 4.2/100. Based on airport operations, weather, and cached board history at EWR and SDF.
The verdict above is that record speaking, so it reflects how UA4520 operates rather than what the timetable promises. Numbers refresh as new flights operate.
Planning around UA4520? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — UA4520 New York to Louisville on-time performance, measured from the EWR and SDF airport boards.
https://proflightsearch.com/flight/UA4520
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