9K5621 NantucketACK BostonBOS · 20:45
9K5621 by Cape Air flies from Nantucket (ACK) to Boston (BOS).
scheduled from ACK
The route today
live boardsWhen it flies
scheduled departuresEach mark is a scheduled departure at its origin-local time. Today is highlighted.
How 9K5621 actually runs
Pro Flight Search has tracked every published board update for 9K5621 across the ACK and BOS boards: schedule changes, gate pushes and actual clocks. Combined risk score: 50.0/100. Based on airport operations, weather, and cached board history at ACK and BOS.
The verdict above is that record speaking, so it reflects how 9K5621 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 ACK and BOS published them.
Planning around 9K5621? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — 9K5621 Nantucket to Boston on-time performance, measured from the ACK and BOS airport boards.
https://proflightsearch.com/flight/9K5621
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