were frequently disrupted by the  Plumbbob  series of atomic tests, which detonated over two-dozen devices at the NTS. The  Plumbbob-Hood  explosion on July 5 scattered  fallout  across Groom and forced a temporary evacuation. The OXCART program Main articles:  Lockheed A-12  and  SR-71 Blackbird A-12 during radar testing at Groom Lake Even