New footage taken from a helicopter has shown entire mountainsides on fire as the William Fire burns up almost 6,000 acres.The William Fire is in the mountains just south of Santaquin, central Utah, and was started by "target shooting" at around 1:50pm, 6th September.In recent days the fire has doubled in size due to hot weather and strong winds, with smoke and flames enveloping the rugged mountainsides.It is now only 62 per cent contained, but the 260 firefighters dealing with it are hoping to have it under control by next Monday, 28th.