Standing next to him, with her hands folded behind her back, Jeon grimaced. "The ballistics formulae incorporate a degree of error, but on hitting an orbital target these projectiles should break apart like antipersonnel bullets to inflict maximum damage. Missing the target and entering atmosphere, they should quickly burn off their cases, then break apart and burn up before reaching the planet's surface."
"Should?" Harald repeated.
"We can't be entirely certain with a ton of iron travelling at such speeds. At the worst, one in ten will forge-weld into one single lump on atmospheric impact, and retain coherence long enough to strike the ground as a plasma column, but thereafter there's a less than point one per cent chance of hitting a major population centre."
Harald nodded slowly, then pushed his microphone across in front of his mouth. "Run test," he ordered.
After a moment the hum dropped to a lower note, which it held for a couple of seconds before rising back to its previous level. Through Harald's headset, his gunnery officer informed him, "Resonance in coils four and fifteen, but within operational parameters." Harald flipped his eye-screen back into position and read the data feeds from the other five hilldiggers chosen for this chore. Four of them were ready, but one had detected major faults in its linear accelerator. How surprising that one should be Davidson's Resilience. However, Harald had already factored in that at least one hilldigger would be unable to fire.
"Estimated damage such a forge-welded lump could cause?" he enquired of Jeon.
"About five hundred kilotons."
"Enough to take out a small city, then."
"Yes."
Harald stared down at his hands and observed how he was white-knuckling the rail. He deliberately relaxed his fingers. "Commence firing," he ordered over general com.
Down below, a snake of missiles advanced one segment down a conveyor, an arm slid one translucent yellow bullet—in which could be seen dark iron bones—into one of the two inner breech sections. With a hiss this section slid down into place in the vacuum breech. The hum dropped to a low note. Simultaneously the second inner breech section clonked across, and another projectile was fed into that too. The hum rose as the first section retracted, dropped again as the next fed in. So it continued for the first five shots—the motion similar to that of a simple pump. Then, after these second-stage test shots, the firing accelerated until the hum never rose again; the breech sections were in constant motion with projectiles being fired once every second.
Harald summoned up an exterior view of the fleet, but there was very little to see as the projectiles departed at near relativistic speeds other than the occasional spurt of a drive flame to keep the hilldiggers in position. The time until the projectiles reached their targets was one hour, but within only a few minutes Director Gneiss and the rest of the Oversight Committee would know Combine was being fired upon. Harald now keyed into feeds from Fleet stations all around Sudoria and flicked through multiple views, observing landing craft in the process of evacuation, as ordered previously. Accounting for the transmission delay, those craft should already be on their way down to the planet's surface. Quite probably the personnel aboard would be arrested once the wardens managed to reach them, but that was a problem to be resolved later. Those personnel would be safer in custody on the surface, for most certainly, knowing it was under attack, Combine would react fast to remove Fleet eyes from orbit. He waited, constantly checking the time display.
The smell of heating metal filled the air, and the accelerator's loading gear continued to produce its fast metronomic racket. Over the last three minutes the five ships had fired over a thousand projectiles. Gun technicians constantly monitored their displays, hands at rest as the machinery did its work. A pause. Misload. One of the breech sections dropped down and swung aside, as one of the five spares slid into place. Harald observed a hydraulic plunger shoving the misfire out of that particular section. The resin body of the projectile was cracked, exposing the iron inside, and when it crashed into the reject shoot, it fell in half. That would have to be investigated but Harald was not over concerned, since errors were certain to arise when using a new design of projectile like this. At least no manual intervention had been required. As the end of the load came in sight on the conveyor, it became easier to see how fast these objects were being fired. Harald tracked the last one down, saw it safely on its way, listened to the hum rise again, steady, then slowly fade.
He was utterly committed now; there was no way to recall those shots.
Again he checked his time display; in a few minutes' time he would know Orbital Combine's response. When it finally came, it was not unexpected.
One display feed from Sudoria blinked out, while another showed the reason why: a Fleet supply station—a cylinder 4,000 feet long and half as much wide—hung in space now ripped open, gutted by incandescent fire. Harald guessed some hot-burning chemical warhead had been used. Then another station—a trans-shipment base for Fleet personnel consisting of four similar cylinders joined end to end—flew apart in a fusillade of rail-gun strikes directed from above. Internal atmosphere exploded into vacuum and something detonated inside one of the cylinders, tearing it open and causing all four of them to separate. Harald could see how Combine was using methods that reduced the chances of too many fast-travelling, dangerous chunks of debris going into orbit, as the previous firebomb, and now the rail-gun missiles were fired from above, so any misses or pieces of shattered station would travel on downward to burn up in atmosphere.
Coverage then became even more intermittent as Harald lost feed after feed. He felt a twisting in his gut upon seeing a watch platform destroyed just moments after a lander had departed it. There the evacuation had been tardy and the lander, struck by following debris, tumbled out of control. He never saw if the pilot regained control; suspected the first Fleet casualties.
"Reposition to second strike point," he ordered over general com. "Evasive course correction on Ironfist's lead. Prepare second loads."
He felt the rumble of drives starting, followed by a sideways drag of acceleration. In the Bridge the gravity floors would correct for the latter, but not down here. On his eye-screen he observed multiple drive flames igniting; the main fusion engines of hilldiggers and support ships, and the blue-red spears of steering thrusters. His diminishing view of events around Sudoria showed nothing being fired in this direction just yet. Perhaps they were not prepared to fire on the fleet itself until there were no more Fleet observation posts left in orbit, but more likely Combine considered it not worth wasting the ammunition, knowing their targets could move out of the way long before anything had a chance of reaching them.
The last feed from Sudoria orbit winked out, but there were still telescope views from the surface on night-side. As expected, the tacom aboard Wildfire, to whom Harald had assigned the task of monitoring Sudoria com, contacted him.
"I am receiving messages from our groundside bases. GDS wardens are now withdrawing from any of those bases they haven't taken. In those they have captured they are closing down all feeds. All the commanders of bases still in our control have received a message from Combine that they are to hand over control to GDS immediately. Otherwise, all those bases remaining under Fleet control will be destroyed. Their commanders have half an hour in which to comply."
"What about bases in urban areas?" Harald asked.