From Kabul, refugees were sent to military bases in Qatar and Germany, and from there they’re being flown to Washington Dulles on U.S. airlines paid for charter flights under the Civil Reserve Air Fleet program. Each person is vetted prior to boarding a flight, and then goes through immigration formalities again in the U.S.
But without documents, there’s been huge bureaucratic delays at Washington Dulles with people waiting 8-12 hours to get off of planes. Flight attendants have been told to pack their own water and anticipate harrowing conditions.