Here's an interesting article that talks about using a cell phone in the air to get clearance to fly an ILS into Helena, MT. What really intrigued me was that the pilot dialed 911, and felt that the signal was louder and clearer than when he tried to dial a number on the phone. He pointed out something I hadn't thought about, which is that the FCC requires all carriers to forward 911 calls, regardless of whether a caller subscribes to their carrier. So as the writer said, "our call to 9-1-1 was picked up by the nearest tower, not the nearest tower of my brother’s carrier." Good information to know if you're in a remote area and not getting good service from your wireless provider!