We were at the beach directly in front of the site when the plane crashed...we had noticed that at one point the plane approached the beach and had left a trail of smoke as it climbed steeply into the air as if it was going to sky write. The smoke color was blue white then changing to a black color as it gained altitude. As it leveled off headed west the smoke trail ended. Unconcerned, I turned away. A young girl (my neighbor's house guest)suddenly yelled the plane crashed. I turned and saw the a small smoking aspot and reached for my camera. As I immediately began to take photos using my zoom, I yelled for anyone with a cell to call 911. It was at least 10 minutes before the(coastguard?) boat from the west (Destin/Crystal Beach? area) and a person on a jetski from the east(Sandestin beach area)to simultaneously arrive at the crash location. The person on the jetski circled the area as the larger craft stationed itself slightly to the west of the crash site. While watching the burning wreckage, I saw two distinctly separate "flare ups and releases of black smoke" as if there were two different fueled explosions. I asked the young girl exactly what she had seen and she said the plane was coming down in a dive and then it had "spun twice before hitting the water".