Not sure if this was an inflight CSC but the Phantom 3 Pro just fellout of the sky. First flight of the day , I was in IOC mode , course Lock mode. P3 had been flying well. I was maybe 400 ft away and about 80 feet hight. I had the right control down bringing the P3 closer to me and descending with the left control . P3 lost power and dropped out of the sky. Can I have possibly gone into CSC mode?? Lucky for me it landed in a grassy area , just slight damage to one of the landing gears. I not 100% sure but I might have had both controls in down position since I was bringing the P3 closer to me and descending. Any thoughts or ideas would be greatly appreciated.