I would like to fly my Mini about 10 or 20 feet above a river. There is a pedestrian foot bridge that is made entirely of metal, and I would like to stand on this bridge and fly up/down river. I plan on launching the Mini from the parking lot that is located less than 100 feet from the bridge. I'll make sure the home point is set to the parking lot location, good satellites, etc.. Once the Mini is in the air, I plan on letting it hoover above the river bank, while I move to the bridge. My concerns are 1) the bottom sensors on the drone causing a problem if I fly 10 or 20 feet above the river, and 2) compass/IMU issues if I fly the drone over the bridge to film both directions of the river flow. I don't think flying from the bridge will be an issue as long as I take off away from it. Am I making a correct assumption about flying from the bridge in this case? Should I put tape over the downward facing sensors on the Mini for this flight? I will have good line of sight on the Mini from the bridge in both directions, so signal strength shouldn't be an issue. Also, I have about 10 flights, so I am a new pilot. Please take that into consideration when you respond, as this might change your opinion. Thanks for your advice....