I am not sure if it is GTE, I generally have had the problem on Continental flights, and I have never been able to 'swipe' my Sprint card on those flights, but I can (& when forced) do use my VISA. The problem is, my Sprint bill gets paid directly by my company, whereas, with a credit card, I have to go through the process of waiting for the bill and then expensing it. We used to have MCI and it was soooooo much simplier.