UA3520 LouisvilleSDF · 10:25 ChicagoORD · 11:05
UA3520 by United Airlines flies from Louisville (SDF) to Chicago (ORD) for the Tue, Oct 13 departure.
arrival expected at ORD · on schedule
board checked 11m ago · checking again in 45s
⚖ UA3520 typically leaves +14 and lands −6. The air wins minutes back.Where the minutes go
last 7 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 −6 min · 0 cancelled · 9 operations tracked
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at SDF and ORD 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 Louisville to Chicago flights today
same route · United AirlinesIf UA3520 is cancelled, these are the other United Airlines nonstop flights from Louisville to Chicago on the same day, with scheduled departure times in SDF local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA3520 actually runs
Pro Flight Search has tracked every published board update for UA3520 across the SDF and ORD boards: schedule changes, gate pushes and actual clocks. Usually lands ~6 min early. Based on 8 confirmed landings · 7/8 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how UA3520 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: N747YX, N741YX, N788YX, N783YX.
Board clocks recorded as SDF and ORD published them.
Planning around UA3520? 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 — UA3520 Louisville to Chicago on-time performance, measured from the SDF and ORD airport boards.
https://proflightsearch.com/flight/UA3520
.