People here often post questions about flying domestically when they're at various beginning stages of the immigration process. Answers vary from "carry your complete current documentation with you" to "you will have no problems."   Customs & Border Protection agents sometimes hang out at the TSA airport checkpoints. In August 2015, I flew out of a border-area airport in south Texas and took the opportunity to query the CBP agents at the TSA checkpoint.   T-B.: When you h