Do you mean commercial flights? No, we don't get to fly commercial flights for free. The only "free" flights we get are ones that are related to an assignment, where we must be flown in order to do our job.
With military fights, you could try to do a Space A, but the availability is rather unpredictable. So, if you are wanting to get home to visit family, the most likely and predictable option is to fly commercial.
