by Paul Preuss
“Why do you insist it was sabotaged, Inspector?” he protested. “Why not an accident? These things have failed before, haven’t they?”
“Occasionally.” It was an understatement. Sparta knew that the electromagnetic launcher at Cayley had suffered glitches aplenty in the early days. Firing five ten-kilogram blocks of sintered moon rock every second for days at a time, the stress on the Cayley launcher was great enough to cause numerous power-control failures. While the area downrange was somewhat safer than a shooting gallery, a thin swath of the moon to the east of Cayley was peppered with meter-wide craters, punched by blocks that fell short.
The engineers who built the big launcher at Farside had benefited from Cayley’s experience. Cliff Leyland’s accident was the first time Farside’s launcher had ever failed during a launch.
“I can’t prove it was deliberate or that you were singled out,” she said, and smiled. “In fact, I admit it doesn’t seem likely, unless this woman you tangled with is the archetype of a vengeful harpy—but I’m simple-minded. I have to start the investigation somewhere.”
Leyland, almost against his wishes, smiled with her. “Well—if someone is trying to kill me—perhaps I should actually thank you for keeping me here.”
“I hoped you’d understand. Just a few more questions, Mr. Leyland…”
An hour later she was falling toward Farside, a passive rider in a capsule like the one that Clifford Leyland had abandoned in mid-flight; rather than ride a Space Board cutter to the surface, she wanted to sample as much of Leyland’s experience as possible.
She’d cleared him to continue his interrupted journey to Earth. The poor man’s long-awaited homecoming was about to be spoiled by howling newshounds, one reason the Space Board had kept him at L-1—not to protect him from murderers but from the media.
For her, it would be a sleepy ride, and then she would set foot on the busy moon for the first time…
PART
5
AT THE
CROSSROADS
14
They sent a moon buggy to fetch her from the landing field. She spent half-an-hour in the tiny office of Farside Security, querying the computer files, before she phoned Van Kessel at launch control. “Inspector Troy, Board of Space Control. Let’s see if we can find out what’s bugging your system, Mr. Van Kessel.”
“I’ll be there to pick you up in twenty minutes,” Van Kessel replied.
“This is where we control the whole operation,” Van Kessel said importantly, as men and women squeezed past him to take their places at their consoles or to get out the door to the trolley stop; Van Kessel and Sparta had arrived in the narrow-tiered control room just as the shift was changing. “Most systems are fully automated,” he said, “but we humans like to keep an eye on what our robot friends are doing.”
Sparta listened without comment as he explained at length the functions of each console station, even though most were self-evident at a glance. This was the first stop on what already promised to be a long tour of the electromagnetic launcher; her head was throbbing again. She focused her attention on the big videoplate screens on the forward wall. They showed that, except for the inactive launcher itself, Farside Base had returned to normal activities.
The only things visibly out of the ordinary were the occasional coruscations of light that played over the concave shadows of the distant radiotelescope antennas. The monitoring camera that viewed the eastern portion of the landscape was mounted halfway down the launcher track; the track stretched away for twenty kilometers toward the sun, and the antennas to one side of it were barely visible in the picture, a wide, flat row of rim-lit circles, like a raft of soap bubbles viewed edge on. The big screen had plenty of resolution, and Sparta’s right eye zoomed in on the sector, enlarging the image of the telescopes. They were racked low, pointing to the southern sky, with their line of aim presently crossing the launch track. The sparks were from electric welders; spacesuited humans and bare metal servos were crawling over the faces of some dishes, patching the damage caused by the debris from “Crater Leyland.”
“Frank, I want you to meet Inspector Troy,” Van Kessel said.
Sparta turned her attention back to the control room. A sandy-haired man in his mid-thirties was smiling at her out of a handsome, artificially tanned face.
“This is Frank Penney, Inspector,” Van Kessel said. “He’s in charge this shift. Frank was the launch director on duty when we encountered our little glitch.”
“You rescued those guys on Venus, didn’t you?” he said with boyish enthusiasm as he reached for her hand. “That was really something.”
“Mr. Penney.” When she shook his hand his grin got wider, showing lots of perfect white teeth. Frank Penney on parade. She couldn’t help but notice his deep chest rippling under his thin short-sleeved shirt, his muscular forearms, the firmness of his grip.
“Hey, it’s really an honor.” His eye held hers. He was pouring on the charm—out of habit.
Sparta tugged her hand free. Her interest in him was not what he hoped. As she watched him she inhaled his faint odor. Under the aftershave perfume and ordinary human sweat there was an odd aroma; its formula popped into her mind unbidden, a complex steroid with unusual side chains. Was Penney hyped on adrenalin? Nothing about him suggested fear or excitement; in fact he seemed quite a cool character.
Van Kessel said, “We’re going to look over the site, Frank, how’d you like to come with us?”
“Great, if you don’t mind.”
“Don’t be silly,” said Van Kessel, playing the gracious boss to Penney’s favored employee. “Let’s get suits on and get out there.”
“That’s the end of the rough acceleration track—twenty-seven kilometers of it—and now we’re coming into the three-kilometer stretch of track for fine-tuned acceleration.”
Van Kessel filled the driver’s seat of the moon buggy to overflowing, with Sparta and Penney squeezed in behind. They were bounding along beside the massive structure of the launcher track, which seemed to stretch endlessly across the level floor of the Mare Moscoviense, and every time Van Kessel raised a gloved hand to gesticulate, the buggy swung dangerously toward the track supports. He was not a good driver. Sparta itched to grab the moon buggy’s controls.
“How rough is rough?” she asked, hoarsely.
“The whole track is built from independently-powered sections, each ten meters long,” he shouted over his shoulders. “Over the whole length of the rough acceleration track we can let them get out of line by up to four or five millimeters. More than that and you get oscillations in the capsule that would shake the teeth out of your head. Also we’re less concerned with the precise acceleration rate here—we let it vary up to a centimeter per second-squared. In the fine-tuned section we tolerate no more than a millimeter variation from a perfectly straight line and no more than a millimeter per second-squared off the ideal acceleration.”
“How do you keep three kilometers of track straight to within one millimeter?” She addressed the question to Penney. Her headache had subsided and she was managing to sound more persuasively interested now, but in fact she had memorized the plans and technical specifications of the Farside launcher before leaving Earth and could call them to consciousness instantly. It was not the sort of knowledge she wanted anyone to know she had.
“The variations aren’t too bad to begin with,” Penney explained. “Mostly expansion and contraction with lunar night and day. And we get a bit of sag between the track supports. The active-alignment technology itself is practically ancient, developed last century for particle accelerators, compound optical telescopes, that stuff.”
Van Kessel broke in. He liked to talk better than he liked to listen. “Basically we’re dealing with laser beams and active track elements—those pistons, you can see them on the supports, that continually push the track this way and that if the beam starts to wander off target. Acceleration is actively controlled by the capsule itself, broadcasting accele
rometer readings to the power-control units on the upcoming section of track.”
“What’s the reason for the fine-tuning?”
“Aim,” said Penney.
“Right,” Van Kessel shouted. “If a load leaves the launcher a centimeter to one side of its true path, or a centimeter per second too fast, it’s going to be hundreds of meters wide by the time it reaches apogee. It could miss the spider web at L-1 altogether. We’re talking dead loads, of course. The capsules can adjust their flight path after they leave the launcher.”
“If the first thirty kilometers of track accelerate the load, what’re the last ten for?” Sparta asked.
“Drift track,” said Penney. “The load is already at escape velocity—that is, it’s supposed to be—and it just glides along without friction while we make final adjustments in aim. At the end the track curves gently away beneath, following the curve of the moon, and the load keeps going straight over the mountains into space, neat as you please.”
Just then Van Kessel jerked the buggy’s yoke to one side and they skidded to a stop. “We’re here. This section is where the phase reversal occurred. Let’s seal up.”
They sealed their helmets. Van Kessel hit the pumps to suck the cockpit air into storage tanks. The buggy’s bubble popped up and they climbed out onto the dark gray rubble that covered the crater floor.
Van Kessel scrambled up one of the squat, saw-horse-like legs that supported the accelerating track. “Watch your step.” Sparta followed him, and Penney came after her.
Sparta stood on the track with the two men. It was lunar morning, and the gleaming, uneroded, unoxidized metal of the quiescent launcher pointed directly at the sun. The loops of the guide magnets circled the three of them. The gleaming loops receded on both sides, seemingly to infinity, constricting until they seemed to become a solid bright tube of metal, finally vanishing in a bright point. It was like looking through a newly cleaned rifle barrel. When she turned and looked in the opposite direction, the sensation was the same.
Torrents of electric current flowed through the accelerating track when it was operating, but for the moment they could walk the track without fear.
“We’ve been over this piece damned carefully,” said Van Kessel. “I don’t think you’ll find much.”
Sparta didn’t answer, only nodded. Then she said, “Wait here, please.” She left the men standing and paced the length of the section, half a kilometer long.
The launcher was a linear induction accelerator—in effect an electric motor unrolled lengthwise. The moving capsule played the role of rotor, while the track played the role of stator. As the capsule, levitated on strong fields generated by its own superconducting magnets, passed from one section of track to the next, the track’s electric fields switched phase behind it and in front of it, pulling it forward ever faster, just as in an electric motor the rotor spins faster as current to the stator is alternated faster.
But if the alternation reverses phase, the rotor can be dragged to a violent halt. Before Sparta visited the control room she examined recordings of the near-fatal launch sequence; they confirmed Van Kessel’s report that the phase had been reversed in these several sections of track during Cliff Leyland’s launch, slowing his capsule so that it failed to achieve escape velocity.
It had taken the trackside monitors a split second to note the failure and switch the track off altogether, preserving the capsule’s momentum. Another fraction of a second passed, and the fields came back on, restoring acceleration to the capsule—but it was too little and too late to boost the capsule to escape velocity.
As Sparta walked the track, inspecting it with senses that would have astonished the two engineers, Sparta could see no sign of damage or tampering. She paused at the accident site and stood quietly a minute. She was about to turn back when suddenly she felt a queer sensation, a kind of queasiness accompanied by an inaudible chittering in her head. She looked around but could see nothing unusual. The sensation passed as quickly as it had come.
Slowly Sparta walked back to where the engineers waited.
“That’s the power-control station for this section?” she asked, nodding to a black box on a post beside the track, bristling with antennas.
“Yes. It’s functioning perfectly. We checked.”
“Bear with me while I make sure I’ve got this straight: as it accelerates, the capsule—or the bucket, for dead loads—transmits coded information about its exact position and rate of acceleration to these power-control stations, telling them what phase and field strength and when to turn the track sections on?”
“Correct.”
“Could the capsule transmit erroneous information? Could it have sent a signal reversing the phase of this section of track?”
“That’s supposed to be impossible. Before the signals are sent, three onboard processors make independent judgments based on the accelerometer readings. Then they vote.”
“So if the capsule sent an erroneous signal,” Sparta said, “either all three processors went crazy in the same way at precisely the same instant, or somebody programmed them to lie.”
Van Kessel nodded solemnly.
Sparta gave him a spare smile. “Mr. Van Kessel, you’re not a reticent man. But you haven’t once mentioned the word sabotage.”
He grinned broadly. “I figured you’d reach that conclusion on your own.”
“I didn’t have to come all the way to the moon to reach that conclusion. Sabotage was apparent from the facts.”
“Oh?” Frank Penney chirped. “You were ahead of us, then.”
“I doubt that. It wasn’t that the launch failed,” she said. “It was the way it failed.”
“Strange, wasn’t it?” Van Kessel said, nodding again. “An adjustment in launch velocity so precise that Leyland’s orbit would bring him right back down where he started. The odds against it are almost impossibly large.”
“And the failure occurred right where you could do nothing to prevent it—not enough track left to accelerate the capsule to launch velocity, and not enough left to stop it without crushing Leyland.”
“Right,” Penney said with relish. “If we’d tried to decelerate him in the drift section, he would have been all over the inside of that thing like a bug on a windshield.”
“I did think it was sabotage,” Van Kessel said, “but old engineers are superstitious. We know that sooner or later anything that can go wrong will go wrong. Murphy’s Law.”
“Yes, and it’s sound statistical thinking. It’s why I wanted to see the hardware for myself.” Sparta was silent a moment, staring in the direction of what everyone was already calling Crater Leyland, far away on the slopes of Mount Tereshkova. She turned. “Can we have a look at the loading shed?”
They climbed down from the launcher and packed themselves into the vehicle. Van Kessel shoved the throttle forward and the big-wheeled buggy wheeled around and galloped off across the moon.
A few minutes later Sparta and Van Kessel were peering through a thick glass window at the interior of the loading shed. The graceless steel barn, lit by rows of bare blue light tubes, stretched for almost half a kilometer beside the launcher track at ground level; a forest of steel posts supported its flat roof.
Penney had gone on to the control room, but the loquacious Van Kessel was delighted to continue squiring Sparta around. “You should see the place when it’s working,” he said. “All those tracks are full of capsules shunting along like cars on a carnival ride.”
The floor of the huge shed was a switching yard, a spaghetti platter of magnetic tracks, laid out so that empty capsules and buckets for dead loads could be loaded at the far side of the shed and shunted forward gradually, one at a time, steered to their designated places in line. As the capsules approached the launcher they were grabbed by stronger fields and shoved into its breech.
“The launcher can handle up to one capsule or bucket a second,” Van Kessel said. “Since the track is built in sections, each load is independen
tly accelerated even if thirty loads are all traveling down it at once.”
Dead loads and inert freight capsules were handled by robot trucks and overhead cranes, but for human passengers and other fragile cargo a pressurized room with docking tubes was provided at one end of the shed. Sparta and Van Kessel were in it now, standing before its big window, still suited, their helmets unlatched. Waiting capsules were lined up at platform’s edge. The place had all the charm of a subway platform.
Out in the shed nothing moved accept dancing shadows cast by a lone robot’s welding torch. Sparta turned away from the window. She ducked through one of the docking tubes and squeezed through the hatch into an empty capsule.
She spent a moment confirming that the interior layout was identical to that of the capsule she’d ridden to the Moon—control panel, acceleration couches, baggage nets, emergency supplies and all. “How long do you give passengers to get aboard?” she called to Van Kessel.
“We like them here an hour early, but people who travel a lot can usually get themselves strapped in and do a system check pretty quickly—ten minutes or so.” Van Kessel extended his hand to help her as she climbed back out of the docking tube. “We have manned-launch attendants here to assist.”
“So passengers don’t walk in and take any available capsule?”
“No, the capsule’s are designated in advance, usually the day before. We don’t like to send up any extra mass that has to come back down again, so we talk to L-1 and try to calculate the return trip fuel requirements at this end.”
“Whoever sabotaged the capsule could have known a day in advance that Cliff Leyland was going to be in it alone?”
“That’s right. Like now—we’ve got a dozen people waiting right now for us to clear the launcher. Every one of these capsules is earmarked in launch order.”
“Yet we’re free to climb in and out of them?”
“If we weren’t who we are, Inspector, I assure you we couldn’t have gotten into this area. It’s well guarded—by robot systems that don’t stop to ask questions.”