Laos. On 15 November 1968, the Seventh/Thirteenth Air Force had inaugurated Operation Commando Hunt, a series of continuous interdiction operations against the Ho Chi Minh Trail that would continue until the end of American participation in the war. For the next four years Igloo White and Commando Hunt would be interlinked in the anti-infiltration effort. With the advent of Igloo White/Commando Hunt, the aerial interdiction effort entered a new phase. Armed reconnaissance – the patrolling of known segments of the trail system by aircraft searching for targets of opportunity – gave way to strikes directed by the sensor system. That is not to say the Task Force Alpha had operational control of the aircraft that carried out the missions. The Seventh Air Force was not about to surrender the single air manager control that it had just fought so hard to obtain. Task Force Alpha supported the Seventh by gathering, analyzing, and disseminating intelligence. This intelligence was delivered from Nakhon Phanom to the Seventh's headquarters at Ton Son Nhut Air Base, where it issued the strike orders. The ABCCCs were also under the control of the Seventh, not Task Force Alpha. The only exception to this arrangement was Operation Commando Bolt, a real-time, LORAN-based technique which utilized sensor strike zones derived from predicted target locations. These missions were coordinated by Task Force Alpha's Sycamore control center against targets that passed through strike modules (four strings of three to six sensors each). Air controllers at Sycamore then directly delivered the correct course, altitude, and speed necessary for the strike aircraft to deliver their ordnance to the correct coordinates. There were some initial problems with the system. During Operation Commando Hunt I, for example, there were so many aircraft piling up in the air space over southern Laos that the air controllers and FACs could not keep track of them. Pilots, many of whom were veterans of Rolling Thunder, tended to arrive over the area in large waves instead of spacing out their arrivals over time. One technical failure, however, would have huge ramifications for the entire program. The anti-personnel system, which was based on the dispersal of wide-area Gravel mines (the explosions of which would activate acoustic sensors) failed completely. The mines deteriorated too rapidly in the heat and humidity of Laos, thereby negating the system. The North Vietnamese response to the threat posed by the sensors was swift. If PAVN