Читать книгу Delta G - David J. Crawford - Страница 6

Standing on an aluminum grated platform 150 feet atop a Titan II ICBM silo, a technician is tightening a fixture with a nine pound socket wrench. As he struggles to get a good grip, it slips out of his hand and falls between the work platform and the missile. Just like Newton’s apple, it accelerates downward, tumbling as it falls. It makes a metallic clanging noise when it hits the missile’s thrust mount, and then ricochets up into the bottom of the first stage fuel tank making a sickening thud. This was then followed by a voice shouting the two most uttered words heard at all accidents and catastrophes. “Oh, shit!” echoed off the silo walls.

A few hours later and a thousand miles away, the sound of footsteps flying up the narrow wooden stairs roused newly commissioned Second Lieutenant David Sheridan out of his bed. His father was racing upstairs to wake him up and tell him a missile silo had blown up. It was one of his missile silos, or at least, soon to be his, in a manner of speaking. Sheridan had just been commissioned from the Air Force Officer Training School, known as OTS, in San Antonio, Texas. He was home on leave in northwest Ohio prior to heading to his first assignment. Sheridan was assigned as a missile engineer with the 308th Strategic Missile Wing just north of Little Rock, Arkansas.

Dave threw on his pants and raced downstairs. CBS news was reporting that a huge explosion had just shaken north central Arkansas and that towns were being evacuated and the entire area was being cordoned off. It wasn’t known yet if there was an actual nuclear detonation. It was Friday, September 19, 1980.

The Titan II carried the largest warhead in the US inventory. An Office of Technology Assessment study had estimated that a 10 megaton air burst on Leningrad would result in 2.4 million fatalities and 1.1 million injuries.

As more and more information trickled in, it was reported that an Air Force technician doing routine maintenance in the silo had dropped a wrench which rolled off a work platform and fell to the bottom of the silo. The socket bounced off the thrust mount and struck the missile, causing a leak from a pressurized fuel tank. The missile complex and surrounding area was evacuated. Eight and a half hours later, hypergolic fuel vapors within the silo ignited and exploded with enough force to blow the 740 ton silo door several hundred yards. The incident was classified as a Broken Arrow and would trigger events and procedures for the Strategic Air Command to locate, secure, and recover the ten megaton nuclear warhead that was found six hundred feet away in a drainage ditch. The explosion killed an Air Force specialist and injured twenty-one other USAF personnel.

When Second Lieutenant Sheridan arrived at Little Rock AFB the following week, all hell was breaking out. Talk about your baptism with fire. Sheridan was escorted from the base personnel office by his new sponsor and supervisor, Major Larry Norris. Norris explained how things were very hectic and that it may take a couple of weeks for things to die down and get back to normal. Little did they know, normalcy never would come back to Little Rock AFB. On his way to his new office, Norris brought Sheridan into the Missile Maintenance facility. Laid out on the concrete floor were several shards of twisted metal. Also, what looked like two sets of astronaut suits were laying in a far corner. They were shredded and blood stained as if someone had blasted them a dozen times with a shot gun. One helmet was cracked in a half dozen places. Norris explained that these were the RFHCO or Rocket Fuel Handlers Clothing Outfits worn by two airmen that had volunteered to take explosive fuel vapor buildup readings in the silo just before it exploded. They had just registered and reported explosive level readings pegging the needle and were exiting the silo entrance portal when the blast occurred. One airman was relatively sheltered behind the silo portal door. The other was peppered with shrapnel, concrete, and gravel. He lived only a short while.

Lieutenant Sheridan moved into his new office. He was introduced to Bill Green, a civilian engineer, who had been on the base for nearly twenty years. He also met Chief Mitchell. One piece of advice he remembered from OTS was that when you have an opportunity to work closely with a chief master sergeant, latch on to him and then soak up all the experience and knowledge you can. Between Bill and the Chief, there was nearly fifty years of missile experience to glean.

Bill had arranged for a site visit the next week to an operational missile site. Before that, the days were spent in safety training and security training. This also meant Sheridan had to come up to speed quickly and become intimately familiar with the Titan II systems and their silos. He spent the next week pouring over the weapon system drawings, operations manuals, and schematics.

On the surface, the Titan II launch facilities covered an area of approximately 600 x 600 feet or about eight acres. All of the launch facilities were underground. The silo was built of heavily reinforced concrete, and was 147 feet deep and 55 feet in diameter. They were designed to be “hot launched” from within the silo. To deflect and channel the exhaust gases, each silo was fitted with a flame deflector at the base and two exhaust ducts that ran up the length of the silo, venting to the surface. Inside the silo there were nine levels of equipment rooms and missile access spaces. The 740 ton steel and concrete silo door could be opened in 17 to 20 seconds.

The silo was connected to the missile control center by a 250 foot long access tunnel. Between the silo and the launch control center was the blast lock, a single level, heavily reinforced concrete structure containing three rooms. To enter the launch facility the missile crews descended through a 35 foot deep access portal that opened into the blast lock area. Each end of the blast lock was covered by a pair of large steel blast doors, each weighing 6,000 pounds. They were designed to protect the launch center from either a surface nuclear blast, or the explosion of the missile within the silo. The doors were designed to withstand an overpressure of 1000 psi; while being so perfectly balanced on their hinges, a single person could manually open them.

The launch control center was a dome-shaped, reinforced concrete structure 37 feet in diameter containing three levels. The three floors within the launch center were suspended from the ceiling by massive springs to minimize blast shock. The control center provided space for all of the launch control and communications equipment, as well as a mess and sleeping quarters for the four-person combat crew.

The TITAN II ICBM measured 110 feet in length and 10 feet in diameter, utilized in excess of 200,000 pounds of two part hypergolic propellant, igniting on contact, and produced 530,000 pounds of thrust. The TITAN II had a target range of 5,500 miles.

It is a two stage liquid fueled booster, designed to provide a small to medium weight class capability and able to lift approximately 4,200 pounds into a polar low-Earth circular orbit.

There were 54 Titan IIs placed on alert despite the fielding of more than 1,000 of the much easier to operate solid fueled LGM-30 Minuteman. This was because the huge 10 megaton warheads of these few Titan IIs represented almost 30 percent of the overall ICBM megatonage of the USAF’s Strategic Air Command (SAC).

The Titan II was a very reliable missile; it was therefore used by NASA in the Gemini manned spaceflight program. Initially, the USAF made very limited use of the Titan II as a space launch vehicle under the strategic launch vehicle (SLV-4) designator.

Sheridan’s first official task as a newly commissioned officer was to support the accident investigation and assist in disaster recovery. This included methods to monitor groundwater contamination and assist in fuel decontamination of the destroyed silo.

Bill made arrangements to get a base chopper to ferry them out to Silo 4-7 early that morning. When they arrived at the helicopter operations center, both went through the safety and preflight brief and then walked out onto the ramp. The sun was just coming up and it was hoped that the fog would burn off before they got airborne and out to the site. This was his first chopper flight and he couldn’t wait. The crew chief helped him strap in. The seat belt and shoulder straps had a weird quick-release system. After he was snugged up, the crew chief just smiled, gave a com check on the intercom headset, and then pointed to where the barf bags were. The unwritten rule was if you chuck it up, you cleaned it up. It didn’t matter if you were a buck sergeant or a four star general.

After the preflight and all the “remove before flight” ribbons were removed, the flight crew hopped in. This was going to be a training flight. There was another butter bar in the right seat of the chopper. The turbines were started, radios set, flight instruments set, and then rotors engaged. The rpm spun up and the chopper began to shake violently.

Several rivets, screws, nuts, and bolts were dancing around the floor. The crew chief grinned and calmly pulled out a whisk broom to sweep them into a coffee can. “More of these where those came from, Lieutenant.”

Just then the pilot pulled on the collective stick and the chopper rose about ten feet off the ramp. The chopper hovered for a while and then taxied off the ramp onto the runway. As the pilot pushed in the cyclic stick, the good ol’ Huey nosed downward. It looked like the ramp was going to smack them all in the face. Instead, the chopper hung nose down as it accelerated down the runway gaining altitude on its outbound trek.

By this time, the fog was burning off and the sun was rising as a big beautiful orange ball on the horizon. The chopper turned north and climbed over a ridge line. Complex 374-7, as it was known, was about sixty miles northwest of the base near a little town called Damascus. The chopper flight was exhilarating.

Up until this time Dave had only flown a total of four times. Once when he was thirteen after spending the summer with a friend in Massachusetts and he flew home in a 727. His father took him up in a Cessna when he was fourteen. His last flight was his flight from Columbus, Ohio to Texas and back after Officer Training School (OTS). He soaked up the experience.

As an engineer he couldn’t keep his eyes off the instruments. The crew enjoyed flying with a novice. They did not intentionally try to get him to puke his guts out. Nobody likes the smell of barf. But they did like to show off their piloting skills. The pilot dropped the chopper down to about a hundred feet off the deck.

He told the crew, “We’re now crossing the Fort Chafe Army Base, federal land. No need to worry about scaring the cows and chickens here. We’re going to do some low level VFR work here.” In other words, they were going to fly around using visual flight rules to check out the float streams.

They followed a stream and Dave overheard the pilot tell his copilot, “That’s where I’m putting my float boat in this weekend to catch beaucoup mega bass.” The chopper continued to follow the stream and then climbed sharply and turned back to the north.

The pilot said, “Enough fun and games, don’t know if we’re going to be able to get you guys in out there. The fog is still fairly thick at 4-7. We might have to shoot some instrument approaches to hone our skills. I’m going over the lake to do some instrument work.”

They spent the next half hour practicing instrument turns. You couldn’t tell up from down. They were flying in and out of a fog bank over the lake. Every time they’d turn into the fog bank it was like flying through a milk bottle. Dave was experiencing vertigo, but he held his own. He kept his stomach contents down.

“Okay, we’re going to continue out bound to 4-7. The sun is starting to thin this stuff out,” the pilot said. The chopper turned to the north, flew along a highway for several minutes and then started to circle the site. The fog had burned off enough for them to look down and see a gaping hole in the ground about 150 feet wide. Chunks of concrete and debris were scattered everywhere. The pilot lined the chopper up for the helipad and made a slow approach.

He said, “Okay, Mike, this one is all yours. You have the aircraft.”

The young copilot replied, “Roger, sir, I have the aircraft. Pre-landing checklist is complete.”

The crew chief spoke up, “Tail clear left and right.”

The chopper hovered ten feet off the pad. The power and pitch were adjusted and the Huey made a nice bounce on the pad. The pilot chided the young lieutenant. “You rushed that one a little bit. We’ll have to work on that.” After the chopper shut down, Bill and Dave climbed out and they walked up to the entry control point a hundred yards up the road.

It didn’t take long for things to make an impression on his first visit at the destroyed missile complex. After passing through the entry control point and walking up the site access road, they noticed a half dozen vehicles strewn about. These were remnants of the maintenance crew vehicles after the explosion. Most had their windows blown out. One pickup had both doors blown off. There were twenty to thirty people on the complex that day. Anything below ground was still strictly off limits. There was no radiation hazard. However, the hydrazine and nitrogen tetroxide fuels were highly toxic and corrosive. There was concern that there might be residual fumes that migrated to the launch control center.

“Unbelievable.” Dave said. “It is hard to believe everyone within a half mile of the complex was not killed.”

Another thing he noticed was that the security fencing surrounding the complex was bent, twisted, and full of holes in several locations.

“What’s that over there?” he asked.

“It’s one of the flame deflectors.” Bill replied. “Those massive steel structures divert the launch exhaust outward away from the missile as it rises out of the silo. They are made of two inch thick high carbon steel.”

The mangled pile of plate steel was about 20 x 40 feet and 10 feet high. It was torn to pieces like a cardboard box, lying in the middle of a bean field several hundred yards away.

Basically the entire silo headworks above level three were peeled back and blasted out of the ground. It reminded him of a shotgun barrel that got plugged and then shredded after pulling the trigger. There were massive pieces of equipment, chunks of concrete, rebar, wiring, and steel everywhere. Part of the headworks included several ten foot thick I-beams that crisscrossed much like a tic-tac-toe pattern. These structural members were lying in a pile of concrete several hundred yards to the other side of the complex. They couldn’t even see the massive silo closure door. It was blasted over a sixty foot tall pine tree at the back of the complex and landed in a field.

One of Lieutenant Sheridan’s assigned tasks was to calculate the explosive force in kilotonage that resulted in blowing a 740 ton door nearly 750 feet. That was nearly a ton per foot. He got the calculator out and crunched the following numbers:

 The energy in one pound of TNT is about 2,300 BTUs.

 The Titan burns hydrazine as a fuel and has 12,178 BTUs per pound which is nearly six times as energetic as TNT.

 The Titan II carried 104,000 pounds of hydrazine.

 Thus the explosive power in kilotonage of TNT:

104,000 lb x 12,178 BTU/lb

= 1,266,512,000 BTU ÷ 2,300 BTU/lb

= 550,675 lb of TNT.

He thought out loud, “Holy shit! That’s one hell of a big bang! This was equivalent to a small tactical nuke going off.” It came out to over a quarter of a kiloton in explosive force and this didn’t even include the energy in the oxidizer. The Hiroshima atomic bomb was only fifteen kilotons. This was put in the accident investigation report. He was on the job less than two weeks and he was already published.

The young lieutenant walked up to a slab of concrete hanging over the edge of the silo crater. He peered over the edge.

Just then someone yelled, “Get off that, you dumb shit!” A big burley Master Sergeant rushed over yelling more obscenities as he ran. Dave was taken back a little. They didn’t teach you at OTS what to do when a 240 pound, 6 foot NCO calls you a dumb shit and starts running at you.

Just then, Bill raised his hand and yelled back, “Calm down, Mitch. He’s with me.”

Mitch stopped dead in his tracks. He immediately apologized, “Sorry, sir. I didn’t recognize you. However, I must respectfully ask you to step back from the edge. This whole area is in danger of falling into the hole. We’ve got enough problems out here without fishing out a butter bar. No one is allowed near the crater without being tethered off.”

Lieutenant Sheridan gave a professional response, “Thanks for the warning. By the way, I am not a butter bar. I worked hard for these gold bars.”

Mitch responded, “You’re right, Lieutenant, my mistake.”

He reached out his hand and said, “Look, I don’t want to get off on the wrong foot here, especially since it would’ve resulted in a 150 foot drop.” Mitch grabbed it, shook it firmly and smiled.

Bill spoke up, “I hear you’re having some problems with the pumping out here. What’s going on?”

The silo bottom had been filling up with groundwater and rain water the last couple of weeks. There was about thirty feet of water in the hole. They were dumping five gallon buckets of HTC, a pool treating chemical, to neutralize the fuel in the silo. They had lowered a pump down the hole and were attempting to pump it into tanker trucks topside.

Mitch responded to Bill, “We went through three pumps already. We burned out two of them. I’ve sent two guys into town to bring back a couple of bigger pumps. They should be back in a few minutes. We haven’t pumped a drop all morning.”

Bill looked at all the hoses running from the hole to the tanker truck. Just then there was a commotion at the gate. A staff car had pulled up. It was the Wing Commander, Colonel Haase.

When he walked over, everyone stood erect and gave him a crisp SAC salute. Bill reached over to shake his hand. “Good morning, sir.”

“Morning, Bill. Who’s your partner in crime?”

Lieutenant Sheridan immediately spoke up. “Good morning, sir, I’m Dave Sheridan, your new missile engineer.”

The colonel responded, “Welcome to the 308th, I heard we had a new butter bar in the Wing. Sorry, I haven’t had a chance to meet with you since you in-processed. Things have been kind of hectic. Speaking of hectic, SAC HQ and the state EPA are riding my ass. They want to know if we’re contaminating the groundwater up here. They’re worried that the chickens will no longer lay eggs and the cows’ tits will dry up. I heard there is some problem with the water treatment and pumping. What’s going on?”

The brand new lieutenant had his first encounter with an O-6 and was about to show his brilliance. He responded, “Well, sir, from what I can see with these submersible pumps, is that they burned out because they were not the right type to begin with. It is not that they were underpowered. Unlike on Star Trek, more power is not always the best answer.”

Haase looked surprised. Bill just smiled.

Sheridan continued, “What they need here are positive displacement pumps. They are trying to suck water up over 150 feet plus the height of the tanker truck. It’s a physical impossibility to suck water more than about thirty-two feet.”

Haase chuckled, “You mean you gotta blow, not suck. I always heard blow was a figure of speech.”

Dave laughed along with the others. At least, the colonel had a sense of humor. He went on to explain that three, fifteen horse power submersible positive displacement pumps would do the job. “As a matter of fact, you might want to pump up the water and then mix the HTC in the tanker. Then just let some of the water fall back down a hose to the bottom of the silo to insure good mixing and to get into the cracks and voids down there.”

Haase swung around and ordered Sergeant Mitchell to make it so.

They were mixing and pumping water by late that afternoon. Colonel Haase had some positive information to pass on to the generals in Omaha and the state EPA. Dave had come through with flying colors on his first engineering challenge and he impressed the boss.