Alaman had no forces, other than those within Chinampas and the benevolent intervention by friendly government officials, that could be rushed in to lift a siege.
Satisfied that he had all the information that could be safely obtained, Guajardo had begun the methodical process of exploring all options of attack available to him. Once all realistic options had been developed, Guajardo would wargame them, looking for the strength and weakness of each, comparing the advantages and disadvantages of each option before making a decision. This process, which took place in almost total secrecy, spanned several months and, like all obsessions, was never far from Guajardo's mind.
Some options had fallen out almost immediately. A ground attack was impractical. Ideally, such an attack would be conducted at night with no warning. But the Mexican Army lacked night-vision devices and the training that would make such an operation easy and ensure success. The garrison of Chinampas, on the other hand, was lavishly equipped to deal with such a threat. Numerous limited-visibility vision devices, both manned and automated, backed up by several belts of unattended ground sensors and remote monitoring stations, made an undetected approach by more than a handful of men highly unlikely. Besides, all units trained to conduct such commando operations were heavily infiltrated by informers either directly or through those who controlled their deployment and operations.
Unable to use stealth, Guajardo next considered the other extreme: direct and overwhelming conventional attack by regular Army units. As a professional soldier, he could easily organize and conduct such an operation. Though its weapons were not the most sophisticated, the Mexican Army possessed sufficient firepower to wipe Chinampas, and all within its walls, off the face of the earth.
An operation of that nature, however, could not escape detection. As with Mexico's special operations forces, every unit within his military zone, down to company level, had informers either in Alaman's pay or in the pay of another drug lord. Guajardo knew that any movement of major forces would be known in Chinampas even before the troops left their barracks. And even if, by some chance, such advance warning from within the ranks could be prevented, it would be impossible to hide the movement of troops through San Antonia, then north over the only road leading to Chinampas. Either way, while the troops and weapons could be brought to bear, and Chinampas destroyed, Alaman would be long gone before the Mexican Army could fire its first round.
Discarding direct ground attack, Guajardo explored the possibility of reducing Chinampas with air attacks. Together with an Air Force colonel who was a member of the Council of 13, Guajardo worked out the mathematics of such an attack. After looking at every possible combination of aircraft and ordnance available to the Mexican Air Force, both officers agreed that such an attack, though possible, could not guarantee success.
Though Guajardo desired to use a simple, direct, and quick solution, all the options that fit that description failed the most critical test: they did not offer a better than even chance of catching, or killing, Alaman and his key personnel. In a fit of frustration, anger, and irrational rage, Guajardo threw all the data, maps, draft plans, and working papers into his safe, changed the combination, locked it, promptly forgot the combination, and walked away from it. There the matter rested for several months.
It was during a conference at Fort Benning, Georgia, that a viable solution to the Chinampas problem began to form in Guajardo's mind. In one of the sessions dealing with special operations and raids, the briefer presented a short lecture on the American raid on Son Tay. Executed on 21 November 1970, that raid had been meant to liberate sixty-five American POWs held there. Although the operation was expertly executed, it failed because the POWs that had been held there had been moved days before the raid. As Guajardo listened to the lecture and studied the colorful diagrams, he could not help but compare many of the problems that faced the Son Tay planners with those that faced him at Chinampas. Even before the lecture was over, he realized that he had been given the key to the solution. Though a detailed plan had to be developed, from that moment on, Guajardo knew that Chinampas, and all who worked within its walls, would fall to him. All that was needed now was someone to open the safe he had locked.
Realizing that it is a mistake to take the solution to one military problem and apply it blindly to another, Guajardo carefully created his own plan, selectively using tactics and techniques used at Son Tay. An example was the manner in which the Son Tay raiders used helicopters to neutralize the guard towers in 1970. There, a CH-53 with miniguns on both sides flew between two guard towers, hovered at the same level as the towers, and fired the miniguns directly into them. The wooden guard towers at Son Tay, pulverized by miniguns firing 6,000 7.62mm rounds per minute, were, in effect, sawed off their supports. This allowed the initial assault group to come in and land unhindered in an open space in the compound.
Though Guajardo did not have a helicopter as big as the CH-53, or miniguns for that matter, he could improvise. For aircraft, four Bell 206 helicopters, each with a crew of two and capable of carrying five passengers, would be used. Since the Mexican Army had few helicopters, only the towers in the west and the center would be attacked. These four helicopters and their passengers, code named Group Z because it was staging and launching from Zacatecas, would hit Chinampas first. Coming in from the west, each helicopter would fly directly to its designated target, one of the four towers. Flying nap-of-the-earth, Group Z would use the hills west of Chinampas to mask their approach. Once clear of the hills, the pilots would only have a few seconds to orient themselves and line up on the tower they were to hit, all the while making a final high-speed approach.
The challenge that faced each pilot in Group Z was covering the last few meters of open ground as quickly as possible, clearing the outer wall, then rapidly bringing their helicopter to a hover a few meters away from the tower. With a main blade diameter of 11.3 meters, the closest the Bell 206s could come to the tower, or any other obstacle for that matter, was six to eight meters. That, however, was close enough.
Once the pilot or the co-pilot had brought the helicopter to a hover, the other crewmen, armed with automatic rifles, would fire out of their open windows into the guard tower. Guajardo knew this fire would be wildly inaccurate, especially since the crews would not be permitted to practice before the operation in order to preserve secrecy. But it didn't need to be accurate. Guajardo was counting on the surprise assault from the air, coupled with the suppressive fire from the helicopter crew, to allow the passengers enough time to rappel out of the helicopter onto the ground at the base of the tower.
The passengers carried by the Bell 206s were four teams of combat engineers armed with automatic rifles and a variety of explosives. Each team, consisting of an officer, a sergeant, and three sappers, had been hand- picked by a colonel of the engineers who was a member of the Council of 13. During the assault on Chinampas, while the helicopter hovered and the crew fired on the occupants of the tower, the engineers would exit the helicopter using the speed-rappel technique pioneered by the U.S. Army's special operations helicopter group, Task Force 160.
The nylon rope used was two inches thick and stiff. The engineers, wearing leather gloves, would slide down it like firemen dropping down a fire pole. Since the drop would only be twenty feet, even if someone let go, the chances of severe injury would be minimal. Once on the ground at the base of the towers, the engineers, using explosives, would force their way into the tower and clear it as rapidly as possible using gunfire and explosives.
Unlike the pilots, the engineers were allowed to practice exiting the helicopter and the techniques to be used in clearing the towers. To ensure security, each team in Group Z, along with the helicopter and crew that would transport it, was trained in isolation in a different part of Mexico.
None were told what their actual target was. Instead, the men, even the officers in charge, were told that they were being trained to deal with prison riots. To make this'cover story more convincing, the dummy towers and compounds they drilled on were patterned after actual prisons within the state where they were located. Even with this cover story, all rehearsals were classified top secret. Only on June 29, the day before the actual raid, would all members of Group Z be brought together at an abandoned airfield outside of Zacatecas. There, Guajardo himself would issue the actual order for their real target.
Since there was no way of knowing what helicopters and helicopter crews would be available on the day of the raid, Guajardo, who was not a pilot, decided to keep them out of the mission planning. To protect the security of the operation, Guajardo made it a habit to use different helicopter crews. An Air Force colonel on the council advised Guajardo to include the pilots in the rehearsals, but was rebuffed for his efforts. 'This is,' Guajardo told him, 'a ground operation. All the helicopters are needed for is transportation. And for that, all the pilots need to be given is a course, speed, and destination.' Unstated was Guajardo's dislike of aviators, a breed he considered to be overpaid and underworked. So the pilots, like many other participants, would learn of their role at the last minute.
With the two western and two center towers seized or under attack, the door to direct insertion of the main
