I saw that once yesterday, for the first time. I was waiting for my wife at the airport. I assumed it came from the phone trying to connect to the airport's free wifi as I'd set it up to do that when I'd flown a few weeks earlier. I just nuked that wifi connection from my list as I won't be flying again anytime soon.
Samsung S4 (9505), Samsung S3, HTC Evo 4G LTE, HTC Evo 4G, HTC TouchPro 2, HTC 6700 (all Sprint)