Jack Campbell - Leviathan

Geary fought back a curse as he saw that the second Alliance battleship formation had been just too far out, its path just a little too distant from the dark ship formation passing beneath it. Only a few missiles had gone out from both Alliance ships and dark ships as the last Alliance subformation passed, and all of those missiles were caught in hopeless stern chases of their targets.

Destroyers, light cruisers, and heavy cruisers on both sides had traded shots as well. Dozens of Geary’s ships had taken significant damage, as had a score of the dark ship escorts, but with everyone focusing most of their fire on the battleships and battle cruisers, none of the smaller warships had been knocked out.

The encounter hadn’t been a disaster. But it hadn’t inflicted nearly enough damage on the dark ships.

“They split the difference,” Desjani said as she looked at her display. “They assumed you might go for that one wing formation of theirs but also protected against a strike against another part of their formation. Why aren’t we coming back around?”

The question startled him. Why hadn’t he already ordered his fleet to begin the massive turns required to reengage the dark ships? Instead, the Alliance ships were now racing toward…

The jump point for Varandal.

“Let’s see if they chase us,” Geary said.

“But Bhavan—”

“Captain Desjani, the odds are not good here. If we can get those ships to chase us, get them to remain focused on catching and destroying Dauntless , then the defenses at Varandal can help us whittle down their numbers.”

“The dark ships are coming around,” Lieutenant Yuon said.

Geary watched the dark ships swing through the wide turns required by the immense velocities they were traveling, watched them steady up on vectors that were aimed at catching the Alliance ships, waited for them to accelerate so they would be able to slowly catch up with Geary’s warships…

“Why aren’t they accelerating?” Desjani asked after several more minutes. “They’re just hanging back there.”

He didn’t answer, watching the depictions of the dark ship formations, the largest swinging in directly behind Geary’s ships, one of the smaller ones arcing high above and to starward, and the other small dark ship grouping diving down and to port. “I wouldn’t be doing what they’re doing. Why are they doing that?”

“Damned if I know.” Desjani rubbed her chin, eyeing her display. “It feels like they’re trying to herd us, to keep us headed for the jump point for Varandal. Is that their idea? Are they focused now on trying to repel what they think is our attack on Bhavan?”

“That’s possible.” Geary checked something on his display, feeling an odd sensation inside as he looked at the data. “They shed some momentum in their turns, but they haven’t tried to make it up. They haven’t accelerated back up to even point one light, let alone going faster to try to get closer to us. They may be herding us as you say, but they sure as hell aren’t chasing us.”

“Yes.” She twisted her mouth and nodded. “They don’t want us accelerating. Why wouldn’t they want us to increase speed?”

“It looks like they want us to head for the jump point for Varandal,” Geary said.

“And they don’t want us to get there too quickly.” Her gaze went to the jump point. “What do they expect to show up there?”

“If it were I,” Geary said, his voice grim, “I’d be expecting reinforcements.”

She bit her lip, looking down, then laughed softly. “And they’ve got fourteen battle cruisers left. I’ve got to give them credit. They did have a backup plan to get us to come to Bhavan. Their battle cruisers were going to chase us here if we didn’t come on our own.”

“Chase our battle cruisers here,” Geary agreed. “Right into the teeth of that ambush. And now they’ve maneuvered us so we’ll run head-on into those arriving battle cruisers.”

“No. No,” Desjani objected. “How can they possibly time it that well? Another force transiting at least one other star system? How can they be so sure that force is about to arrive here within some fairly compact time frame? What the hell is their margin of error?”

“Captain,” Lieutenant Castries said. Both Geary and Desjani twisted in their seats to look back at her watch station. Castries didn’t quail under the attention of her seniors, but she was clearly choosing her words with care. “Our systems use standard assumptions whenever calculating maneuvers. It’s a percentage of the assessed time, which is based on assuming distance and acceleration/deceleration are all exactly as calculated. Then the maneuvering systems add in the standard error factor.”

“Yes,” Desjani agreed. “And your point is?”

“Captain, the dark ships must be using Alliance maneuvering systems, so they will be using the same standard assumptions as our systems. But we know those are just estimates. We use them, but we don’t assume the standard error figures are going to be exactly right.”

Geary finally understood. “But the artificial intelligences will assume the figures are absolutely accurate. They’ll assume that the probable error estimates can be used just as if they were solid numbers. Which is why they think they can plan for their battle cruiser force to appear before we get to the jump point for Varandal. Captain Desjani, the odds here were already bad. If we end up fighting the dark battle cruisers as well, this bad situation would quickly become ugly.”

He had to admire the way Tanya reacted to the changing circumstances.

“Varandal?” she asked, dropping her earlier insistence on holding the line at Bhavan.

“Yes. We get to the jump point first, we jump for Varandal, then we set up an ambush there, backed up by every defensive resource Varandal has. When the dark ships come through the jump point after us, we’ll hit them hard.”

The necessary orders were easy enough, altering the vectors of the three First Fleet formations a little to bring them on a direct course for the jump point. Figuring out the right acceleration to use was a bit harder given the damage many of his ships had already sustained. “Immediate execute, all units in First Fleet, accelerate to point one five light speed.”

The dark battleships were several light-minutes behind Geary’s ships by now. He waited to see how they would react.

Fourteen minutes after Geary’s ships began accelerating, he got his answer.

“Dark ship formations are braking slightly,” Lieutenant Castries said. “They’re reducing velocity,” she added, sounding baffled.

“They want us to slow down, too,” Desjani said. “That’s a clumsy way to try to influence us, though.”

“It’s all they’ve got,” Geary said. He didn’t feel happy at having guessed right. Instead, he could not stop watching the jump point for Varandal. “Even the dark battleships can’t accelerate fast enough to catch us in the time they’ve got, but I bet they’ll bring their velocity back up once they realize we’re not going to slow down to accommodate their plans.”

“We’ve still got more than eleven hours’ travel time before we get to the jump point,” Desjani said. “Assuming you reduce our velocity down to point one light speed for the jump at a rate that all of the damaged ships can handle.” She glared at her display. “I wish we could have knocked out at least one of their battleships. But that one we beat to hell is still able to keep up with its formation. You know, if those battle cruisers do come through, and we can hit them with all of our battleships…”

He shook his head. “If I were commanding those dark battle cruisers, I wouldn’t seek a direct fight with that many battleships. I’d maneuver to try to hit our formation with the battle cruisers in it, and if I couldn’t do that, I’d try glancing firing passes to wear down the enemy. If we’re lucky, if the enemy battle cruisers come through just before we jump and can’t avoid our formations, we’ll hit them hard and keep going.”