Editing Operation Blowdown (section)

==Preparations==
[[File:OperationBlowdownComposite.png|right|thumb|Map of operations that indicates ground zero, severity of destruction areas, instrumentation lanes and placement of objects to test.]]
The construction of the base camp and test area was provided in part by the 24th Construction Squadron, [[Royal Australian Engineers]].<ref name=OB_01/><ref name=OB_03/> At ground zero, a straight sided tower was constructed to suspend a sphere of TNT charges. The charges were tins of 41 pounds of remelted and cast TNT from 155-mm shells. The final sphere contained a total of 2,438 TNT and 70 CE/TNT booster canisters resting on 408 support blocks with a diameter of approximately {{convert|13|feet}}. Extreme care needed to be taken during construction since damage or air gaps might have caused jetting or deformation of the blast wave.<ref name=OB_01/>

The section of rainforest selected was typical of North Queensland and contained 70 different tree species of varying sizes. Four lanes centred on the tower were set up with instrumentation and one 200-foot wide lane was cleared of vegetation except for select trees to study the impact with varying distances from ground zero. Furthermore, approximately 17,000 trees were catalogued to determine the effects of the blast. Military equipment including light and heavy weapons, mortar pits, ammunition, trenches, aerial masts, wireless communication equipment and cables were also positioned around the blast site, complete with simulated troops.<ref name=OB_01/>