TW421 SeoulICN · 10:40 UlaanbaatarUBN
TW421 by T'way Airlines flies from Seoul (ICN) to Ulaanbaatar (UBN) for the Mon, Aug 17 departure.
en route from ICN to UBN
board checked 9m ago · checking again in 45s
Board estimate · gate and arrival times. Off blocks 11:14 · typical taxi-out at ICN ≈ 5.2 min.
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 operation0 cancelled · 9 operations tracked
The route today
live boardsWhen it flies
scheduled departuresEach mark is a scheduled departure at its origin-local time. Today is highlighted.
How TW421 actually runs
Pro Flight Search has tracked every published board update for TW421 across the ICN and UBN boards: schedule changes, gate pushes and actual clocks. Usually departs ~28 min late. Based on 9 confirmed departures · 0/9 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how TW421 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 ICN and UBN published them.
Planning around TW421? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — TW421 Seoul to Ulaanbaatar on-time performance, measured from the ICN and UBN airport boards.
https://proflightsearch.com/flight/TW421
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