That was the call that would put goose bumps up and down an avionics technician's spine. Fortunately the P3 doesn't have a cockpit, but I had the same quivers going on today. I had gone over to a construction site where our latest high school stadium is being built, to get some overhead shots that my son requested. I did my pre-flight checks, calibrated the compass, and climbed up to 100 ft. I was in a hover, turning toward the stadium, when I saw what appeared to be wisps of white smoke coming from under the quad. I did a landing as fast as I could and shut down. After checking everything, including the battery, and the infamous smell test, I found nothing awry. I flew around the field for several minutes until I was satisfied that all was well, climbed up and got the video. Now I'm thinking that I may have seen either a tiny cloud in the distance, or perhaps even the props creating a vapor vortex. The temp was 81 degrees and 90% humidity today. Has anyone else experienced this phenomenon? Here in Georgia, it's going to get a lot hotter and more humid as the summer comes on in full force. I just want to be prepared for it should it ever happen again. In other news, I have learned how to hand catch the quad now, which is great thing to know how to do when you are in an area where the the field is dirt or gravel.