Denial of visitation

My husband and his ex-wife were divorced in Texas in 1993. We now live in Tennessee. We are supposed to have his youngest son, 9, for 6 weeks summer visitation. His ex has agreed to the dates but now says she will not put him on the plane by himself. He will be on a direct flight, escorted by a flight attendant. He has made the trip several times with his siblings and this is the first time he will be travelling alone. Can she refuse to put him on the plane? Won't she be in contempt of the visitation order by doing so?

Been there- got the tix's, then she said no- what a bunch of BS. Think you will have to file contempt charges in the court where she is, then she says "nuh-uh", I would have sent him. But, if you don't file, it may go on. Can you take the risk, and drive over there? It's three days from Chatt. to El Paso, but if you get him for the summer(?). So many kids at his age ride planes alone. The Flight attendants are very capable of caring for them, and it IS a direct flight.
Welcome Summer