Welcome to Just Answer and thanks for your question. Yes, it is possible to travel with portable oxygen, but it takes some advance preparation and some flexibility. First of all you need to make your reservations well in advance and then ask for the airline's Oxygen Help Desk. They will explain exactly what you have to do (it varies a bit from airline to airline). Be prepared for extra security at check-in and allow even more time than usual to get through the process. Here is an excellent site that tells all about it.