on the bank of the Song Con River, outside the provincial capital of Son Tay. It was a POW camp, and the United States was planning to raid it. The camp was identified in May 1970. Comparison of old and new reconnaissance photos showed a guard tower and new wall had been added. It was also noticed that some uniforms had been spread out on the ground to spell out 'SAR' — search and rescue. In one corner of the compound the letter
The 147SCs were to provide 'prisoner verification' and 'positive identification of the enemy order of battle' — whether the POWs were at the camp, and the defenses in the area. Tragically, the drones went through another bad streak of losses. At least two were shot down, and another four had mechanical failure. The final drone, on July 12, suffered an even more frustrating failure. Two of the POWs, air force Lt. Col. Elmo C. Baker and Capt. Larry E. Carrigan, saw it coming and started waving. The drone was supposed to show 'the height, color, eyes, and facial expressions' of every man in the compound, but the programmer was slightly off; the drone banked a moment too early and the photos showed only the horizon.
Because too many drones flying over so isolated a site would tip off the North Vietnamese, it was decided to switch to SR-71s. The data they brought back was ambiguous — the camp was not as active as before, but there did seem to be someone there. The raid was given a go-ahead.[281]
It started at 2:18 A.M. on November 21, 1970, when an HH-53 helicopter flew over the camp and blasted the guard towers and a guard barracks with minigun fire. Moments later, an HH-3 crash-landed inside the compound with the assault team. They quickly secured the camp and killed the remaining guards. Two more HH-53s with troops landed outside the camp; a third HH-53 mistook another set of buildings four hundred yards away for the camp and landed there. After a short but fierce firefight, the helicopter picked up the troops and flew them to the camp. The raid took only twenty-seven minutes, but no American POWs were found. Unknown to U.S. intelligence, the POWs had been moved out of Son Tay.[282]
In July 1971, the world's political landscape profoundly changed — President Richard M. Nixon announced he would be making a trip to Communist China. Soon after, it was reported that the United States was suspending overflights of China.
As the political situation eased, so did the shroud of secrecy that had enveloped the drones. Since the first loss of a 147 drone in November 1964, the U.S. government had held to a strict 'no comment' policy. During 1970- 71, this began to change. The November 9, 1970, issue of
The year 1971 saw an increase in drone activity, with a total of 406 missions. Unlike previous years, which had seen a host of different 147 versions, only three types of drones were flown. There were 277 SC missions, 120 TE flights, and the final nine 147Hs.[283]
In the war itself, there was little movement. The peace talks, both the public ones in Paris and secret discussions conducted by presidential adviser Henry Kissinger, were deadlocked. The number of U.S. troops declined, even as the antiwar movement grew. The North Vietnamese had used the respite to rebuild and prepare for a ground invasion of the South. As 1971 ended, it was becoming clear that would not be far off.
The drone operation was the first to reflect the impending North Vietnamese invasion. In late December 1971, the sortie rate of SC drones increased to 1.2 per day, twice what it had been. On March 20, 1972, the Easter Offensive was launched. On May 8, Haiphong Harbor was mined, cutting off the North's main source of supply. The Linebacker I bombing campaign began, hitting such targets as bridges, barracks, barges, and rail lines.
With the North Vietnamese invasion, the drones were launched at an average rate of nearly two per day. Some days saw as many as five launches, with nine drone missions flown over a three-day period. This was far higher than during Rolling Thunder. The 147SC drones covered areas that were denied to manned reconnaissance aircraft as too dangerous. This included not only Hanoi and Haiphong, but all of North Vietnam and even occupied areas of South Vietnam.[284]
As the bombing continued during the summer and fall, a new version of the 147SC was introduced. The SC/TV was first flown in June 1972. As the name suggests, this was a standard SC fitted with a television camera. The images were transmitted to a controller aboard the DC-130. He would then guide the drone over the target. This made it possible to cover exactly that part of a target needed. On one SC/TV mission, eight out of nine targets were covered and three bonus targets were also spotted, this despite visibility of down to two miles.[285]
The following month the last of the 147N family began combat operations. The 147NC had an unusual history. It originally was built for dropping radar-jamming chaff and had been operated by the tactical air command for several years. It had not, however, been sent to Vietnam. The chaff was carried in two external pods. It was realized the pods could also carry propaganda leaflets over North Vietnam.
Between July and December 1972, twenty-eight missions were flown by the 147NC drones. The biggest problem faced by the drones was predicting the wind over the target at the time of the drop. The leaflets would drift on the wind after release. Several missions were ineffective because the winds carried the leaflets away from the target. The project's official name was 'Litterbug.' The working troops called the drones 'bullshit bombers.'
In September 1972, a final series of four 147H missions was flown. The cameras were replaced with ELINT equipment. As with the United Effort missions of 1965-66, the purpose of this special project, called 'Compass Cookie,' was to gain radar and fuze data on the SA-2. A number of new versions had been introduced since 1966, and the mission would provide an update. The September 28 mission was fired on by three SA-2s but transmitted the data before being destroyed.[286]
By the fall, a peace agreement seemed complete. Nixon ordered a bombing halt above the twentieth parallel on October 24, while Kissinger declared, 'Peace is at hand.' The final details proved elusive, however. The North Vietnamese reopened several issues and finally broke off talks on December 13. Five days later, B-52s began hitting targets in Hanoi and Haiphong in tlie most intense air campaign in history. Linebacker ll became known as the Eleven-Day War. The B-52s took heavy losses, but devastated airfields, factories, railyards, warehouses, and SAM sites.
Linebacker II saw the drone's heaviest use of the entire war. Between December 20, 1972, and January 19, 1973, over 100 missions were flown.
Two-thirds of these were bomb damage assessment (BDA) missions in support of the B-52 strikes. The photos showed the targets were turned into cratered moonscapes. The drones also photographed POW camps in the Hanoi area. Throughout the war, POWs had seen or heard the drones many times. During the 1968-72 bombing halt, they were one of the few things sustaining the prisoners' morale.
The final B-52 strikes were flown on December 29, 1972. Following a New Year's halt, bombing was restricted to below the twentieth parallel. On January 15, 1973, agreement was reached and all bombing of North Vietnam stopped. It was announced that reconnaissance flights would continue over North Vietnam. They would be conducted by SR-71s and low-altitude drones. One Pentagon official said, 'The use of pilotless drones is no change and is one method we have used whenever bombing missions over North Vietnam have been halted.' It was as close to an official acknowledgment as had been made. The final flight before the cease-fire went into effect was a 147SC/TV, dubbed 'The Last Picture Show.' A total of 570 drone missions had been launched in 1972. Of this, 466 were SC drones (52 were lost), while the 147TEs amounted to a mere 69 flights. [287]
The cease-fire agreement was signed on January 27, 1973. The drones were placed on a 'hold/standby' status. This lasted only five days. Operations resumed with a pair of flights on February 5. The following day, the first of a series of SC/TV missions was launched. Policing the cease-fire was nearly as demanding as Linebacker had been: 444 drone missions were launched in 1973.
