Just want to add my two cents. I'm a new Solo pilot and recently put on new prop guards to give them a whirl (hehe). I launched from a building top (5 stories) which probably wasn't the best idea, but the first minute of the flight everything seemed to be normal, then I flew the drone just past the edge of the building about 4 meters above the height of the building and there must have been some kind of strong downdraft. Solo began rocking violently from side to side and started to rapidly descend...out of my field of view. I hit return to home button but nothing. Ran downstairs and found the camera on the ground and the drone across the street in a mini park...miraculously on its feet! The only thing damaged were the props and the legs extenders had broken off. Looking at the footage the drone struck the building on its way down and the camera fell out. I'm not sure if it hit the building as a result of my pressing the return to home as it was trying to get back or if it was just part of its free fall. Afterward, I brought Solo to an open park, changed the props, fitted the camera, and removed the prop guards and gave it a 5 minute run with no problems. I believe that the prop guards caused extra resistance in unusual/strong wind conditions which destabilized Solo and caused the crash. I found it strange that Solo destabilized and just began to sink like a stone. The only theory I have about why it descended is that there was a strong downdraft along the side of the building. Any thoughts/comments welcome.