Air defences were installed around the Olympic stadium to stop potential suicide airplane attacks, similar to the 9/11 terrorist attacks in the USA. There were six missile sites, four using Rapier missiles and two using Starstreak missiles. After initially announcing the possibility of installing missiles the British government confirmed they would be deployed from mid July. The rapier sites were: * Blackheath Common * Oxleas Wood, Eltham * William Girling Reservoir, Enfield * Barn Hill, Netherstone Farm, near Epping Forest The starstreak sites were: