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xkcd #3124: Grounded
(imgs.xkcd.com)
Title text:
We should have you at the gate in just under two hours--two and a half if we get pulled over.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3124/
I got thrown for a loop by the word bridge too. It having multiple meanings made me wonder if there's a bridge in flying parlance that meant something else. Clearance is also very unspecific.