I turned on my garmin gps receiver on the plane (airtran), after a while got some satellites, and got location and speed. I was told to turn it off since it could interfere with navigation. That dosent make much sense to me, since it receives signals, it dosent really transmit much, other than perhaps set up links with satellites. I remember taking my gps recently on a different carrier and there were no issues then. It is cool seeing 463 mph as the fastest speed recorded on the GPS 