because U.S. matériel and air support are vital. In practice, most operations are conceived by commanders of individual Military Regions in close conjunction with U.S. Military Attachés or in the case of Vang Pao and the other irregulars, with the local CIA Area Chief. *In brief, the U.S. clearance procedures are as follows: The cognizant U.S. military attaché or CIA Area Chief forwards the request to U.S. Country Team, consisting of Ambassador, DCM, Military Attachés and CIA Station Chief. Vang Pao's operations are also cleared by the CIA base at Udom, Thailand which assesses the Agency's ability to provide the necessary support. The Ambassador requests authorization from State for politically sensitive operations or activities exceeding established operating procedures and refers requests for air support to MACV. To combat Northern Vietnamese advancements the United States bombed the Ho Chi Minh Trail along with North Vietnamese troop concentrations in northern Laos. Through the United States Air Force there was an effort that took place to upgrade air operations located in northern Laos. The U.S. Air Force introduced airborne radio direction finding. The EC-47 aircraft could monitor and locate enemy radio transmissions. Colonel Duskin convinced Robert A. Hurwitz that the OV-1 Mohawk could enhance intelligence collections during Barrel Roll which provided night-time reconnaissance. The 1969 communist offensive spurred improvements in the Royal Laotian Air Force as well. Laotian T-28 plane counts jumped from 235 to 1367 in five months. The increase in plane production called for a need for more pilots to be trained. Also, "hampered by monsoon rains, among the heaviest ever seen, ABOUT FACE got underway on 6 August 1969. Eight battalions moved on the Plain of Jars while two more battalions and several hundred Hmong militias approached the road between Ban Ban and Nong Pet. Not to be confused with NangHet, on the Vietnamese border. The significance of Nang Petlay in its location west of Ban Ban at the intersection of Route 7, leading directly into the Plain of Jars, and Route 71, which bypassed the plain to the north. The weather posed more of an obstacle than the communists, who to the attackers' astonished delight abandoned without a fight not only their defensive positions but also major supply dumps. Despite suspected leaks of Vang Pao's intentions, the government forces had achieved complete tactical surprise, and the overextended enemy simply melted away." Even where the enemy had time to react,