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It's springtime in the Sonoran desert. The saguaro and ocotillo are in bloom. Sun gleams on silken sand. Yet something far more menacing than all the rattlesnakes, Gila monsters, and scorpions that populate this broad and bony landscape lurks underground. It's a striking relic of the cold war, the most lethal missile ever built by the U.S. military, with many times the explosive power of the bomb dropped on Hiroshima. Once, 54 such Titan II complexes were poised to launch missiles from U.S. soil. Now just one still crouches in its silo at the Titan Missile Museum in Sahuarita, Arizona.

Part of the second stage of the Titan II missile and its black reentry vehicle (a 9 to 10 megaton warhead) stare upward toward a voyage that will never occur. Each Titan site took 18 months to build and cost $10 million, including the missile, in 1962 dollars.Photographs Courtesy of Titan Missile Museum

Located 24 miles south of downtown Tucson on an arid plain overlooking the Santa Rita Mountains, Air Force Launch Complex 571-7 (as it was then known) was on 24-hour alert from 1963 to 1982. That was a nervous time, and a tour of the silo and the missile deep within evokes feelings of dread. Meant to withstand a nuclear bombardment, site 571-7 is a model of survivability. The 760-ton steel-and-reinforced-concrete door that conceals the missile from the world outside can lift and scrape away up to 6 inches' worth of post-holocaust debris that engineers envisioned might lie on top in a worst-case scenario. Despite its weight, the door rolls back 30 feet in just 20 seconds.

Then it's down a flight of steps into the 146-foot-deep, 55-foot-wide tube. The silo's outer cylinder is an 8-foot-thick concrete shell. In its inner cylinder hangs the rocket: 103 feet long and 10 feet wide, suspended from an enormous thrust mount fixed to the inner cylinder by explosive bolts. The thrust mount is held in place by 20-foot-high springs intended to protect the missile against rocking shocks from a nuclear attack. Everything in this place is mounted on springs or suspended to minimize reverberations from the world outside.

Now it's down a claustrophobic 30-foot hallway, away from the silo and into the control center. Two sets of 6,000-pound steel blast doors, secured by hydraulically actuated steel pins, defend this room and the crew's quarters above against annihilation. There's a foot of space between the inner walls and the floor of the control center that protects against the 430,000-pound thrust of the launching missile.

The missile, in turn, had to be protected from itself. Toxic fumes or errant explosions from the liquid fuel were as much a danger to the crew as the threat of attack. The 25,000 gallons of fuel and oxidizer that propelled the missile would ignite on contact and had to be stored separately on board the rocket. Furthermore, the volatile oxidizer had to be maintained at 60 degrees Fahrenheit, plus or minus no more than two degrees, beneath a scalding desert. Air-conditioning failure was not an option. Should the missile be ordered to launch, 9,000 gallons of water per minute had to be pumped into ducts surrounding the rocket. Otherwise, the noise and vibration would have caused the missile to shake itself to death.

A few details seem antiquated today. The amount of space needed to store computer data shrank so dramatically during Titan II's 19-year tenure that several computer shelves now stand empty in the control room. The same amount of data "could probably fit on a Palm Pilot today," says tour guide Dave Runt, who reenacts the launch procedure by turning a key. Status lights glare from the console. A shrill bell tolls: The missile is ready to fire. A few seconds later, a Klaxon honks: perhaps the last chance to abort. Launch procedures were designed to take less than a minute. The crew did not know where the missile was headed, nor could they call it back.

By the early 1980s, Titan IIs had been replaced by Peacekeeper (MX) missiles, which were smaller and more precise. MX missiles are still armed and ready to go. Titan II missiles have been recycled and are used to launch weather satellites.


Let's Have Sum Fun

Two new games that will really have you counting cards

Cardsharps may not acknowledge it, but when it comes to cribbage, blackjack, and most card games, math rules. And now two new card games help put math back into the spotlight. 1-2-3 OY! ($9.95, uses cards numbered 0 to 16 and wild OY! cards to play 10 different games. One thing most of the games have in common is that the players have to yell "OY!" at some point, so a lack of self-consciousness is a plus. The games center on a target card whose number the players try to reach using their own cards, usually by adding, subtracting, multiplying, or dividing the numbers in their hands. For those who can do more advanced math on the fly, exponents and roots can be added. In an alternate version, players take turns flipping cards from their stacks, held face-down, onto a discard pile. The top two cards are added and subtracted to get two target numbers, and if the next card equals one of those numbers, the first player to shout OY! wins the stack.

Zêtre ($9.95, complicates things by adding three dice and a 30-second time limit. The cards, which come in four suits and are numbered 1 to 10 or lettered Z, Ê, T, R, or E (usually valued at 11 to 15), are dealt seven to a player. The dice are rolled, and the players have to add, subtract, multiply, or divide all three of the dice numbers to match the cards in their hands and then discard as many as possible within a 30-second time limit. If players cannot explain why they were able to discard cards, they must take them back, with penalty cards as well. In case that's not hard enough for you, the letter cards can be made into different numbers depending on their color, and advanced mathematical operations can be added. Fun is the main purpose: Zêtre creator Arte Merritt, who graduated from the Massachusetts Institute of Technology in 1995, says he had dorm parties in mind when he created the game. And OY! creator Don Green says he received a letter from the supervisor of an oil pipeline in Mozambique who complained that the guards patrolling the pipeline were playing OY! all night. Fenella Saunders

With this roll of the dice, which cards can be discarded from this Zêtre hand?


Civil War Acoustic Shadows

Charles D. Ross White Mane Publishing Company, $24.95.

Confederate General Joseph E. Johnston seemed poised for a resounding victory in 1862 at the battle of Seven Pines: His troops outnumbered those of the Union forces. Instead, Johnston wound up with an indecisive draw. The cause, apparently, was acoustics. Although gunfire could be clearly heard five miles distant in Richmond, it failed to carry to Johnston's headquarters just three miles away. Thus Johnston did not hear the start of the battle and failed to send in additional troops at the crucial moment.

Unusual acoustics aided and hindered both the North and South during the Civil War, says Ross, a physicist at Longwood College in Farmville, Virginia. Combining weather records with soldiers' diaries and historical reports, Ross re-creates six dramatic battles and shows how conditions of terrain and atmosphere served to divert sound in unexpected directions, forming an "acoustic shadow." A severe storm blasted Seven Pines the night before the battle; lightning killed several men and destroyed equipment. ("I had witnessed thunderstorms in the tropics but none of them compared to this," wrote one horrified Union cavalry officer.) A high-pressure system pushed the storm off to the east before the battle started and created winds that swirled clockwise, carrying the sounds of the subsequent fighting to the southwest. Johnston, who was camped northwest, was out of earshot.

At another 1862 battle, at Perryville, Kentucky, Union general Don Carlos Buell almost fell victim to an acoustic shadow. Because of drought, air near the ground was extremely hot and caused sound to refract sharply upward. A Union major described the scene: "It was like tearing away a curtain from the front of a great picture . . . At one bound my horse carried me from stillness into the uproar of battle." Buell didn't know of the battle until more than two hours after it began, and as a result, his much larger forces were nearly routed.

Did acoustic shadows determine the outcome of the war? Ross doesn't think so, but they certainly affected specific battles and the careers of several generals, including Robert E. Lee. The Confederate commander rose to power partly due to the debacle at Seven Pines. His loss at the 1865 battle of Five Forks, Virginia— where moisture-laden woods absorbed musket sounds and prevented his generals only a mile and a half away from hearing the start of the fighting— signaled the beginning of the end for the Confederacy. Fenella Saunders

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For a schedule of tours as well as more information about the history of the Titan missile, see titan_01.htm, or call 520-625-7736.

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