Operation Prairie Flat
Operation Prairie Flat was a test involving the detonation of a spherical surface charge of TNT to evaluate airblast, ground shock and thermal effects of nuclear weapons.
Since TNT charges produce roughly double the airburst effect of nuclear weapons, it allowed testing the equivalent of a nuclear weapon surface burst. It was a continuation of the technical co-operation series of tests sponsored jointly by the respective governments. Similar to previous tests, a large number of projects were carried out simultaneously due to the infrequent opportunity and cost of large explosives tests – the United States alone conducted 39 projects. The resulting airblast also allowed testing various targets at a range of overpressures to verify how structures resist effects of nuclear weapons. These included troop field shelters, fiberglass manholes, foxhole overhead covers, blast valves and electrical generators. Debris fracturing and transport were also tested as part of the effort to understand nuclear blast effects on Nike-X anti-ballistic missile sites. An additional goal of the test was to compare the blast with the previous Distant Plain Event 6 that used an equivalent but smaller configuration in order to study scaling factors.