The SADF used weather balloons to trick Cuban air defences in Tchipa (Angola) into action. The Cubans fell for the ruse, launching 6 SA-6 SAMs to blow the harmless balloons out of the sky. The South African observers promptly used the firing data to plot the location of Cuban SAM sites and subjected them to a four-hour-long, 200+ shell, long-range "artillery" bombardment. The much-feared SA-6, the teeth of Communist air defences in Tchipa, were knocked out.