Originally Posted by
megaloman
As US citizen, you have to leave the US using your US passport, so that passport details have to be on your boarding pass
The US does not have formal immigration exit controls. The final manifest, including the passenger information, is transmitted by the airline to the CBP via APIS.
In hundreds of international departures from the US, I have never seen any passport details on my boarding passes, not even when decoding the QR or bar codes. Yes, the passport information is in the PNR.
I stand by my earlier advice