Using the satellite feature in Google maps I was scrolling around Bellevue, Nebraske. Just to the west of Offutt AFB a famer wrote a message in his farm field. The message was captured by the satellite images. Here is a second image that is from a higher vantage point so you can see the runway and the message in the field. I would reccomend that you look at the image I linked to first before you look at the bigger image so that you can see what you are looking for.