The Bombard Gun Takes Shape

Four days after Lin Yuan said those words, progress on the Thunderclap Project was twelve hours faster than he had expected.

March 31, C.E. 71. Underground firing range, weapons testing ground in the western district of the 811 Institute.

Fang Heping mounted a barrel assembly nearly two meters long onto a fixed support. An ammunition belt wound up from the feed box at the side, each link holding a dark gray round the size of an adult's fist.

The spiral grooves gleamed with an oily metallic sheen beneath the firing range's cold lights.

"Is that for an MS?" Han Zheng stood outside the safety line, craning his neck half an inch forward.

"Obviously." Fang Heping patted the recoil buffer ring at the rear of the barrel, his voice hoarse from seven straight days of rushing work. "Seventy-five-millimeter caliber, belt-fed, forty rounds. Every one is a Rocket-Assisted Delayed Implosion Round. Muzzle velocity is eight hundred meters per second, accelerated to fourteen hundred by the rocket stage."

Han Zheng whistled.

"What are you whistling for?" Fang Heping stuffed his wrench back into his tool bag and crouched to inspect the feed box's locking mechanism. "Do you know how much recoil this thing has? The peak impulse of a single shot is six times that of the United Army's standard Dagger autocannon. Six times."

"Black Iron can take it."

"Whether Black Iron can take it is Xu Yanqiu's problem. What I'm telling you now is whether you can take it."

Fang Heping stood up and rubbed the dust off his hands on his work pants.

"After more than three consecutive shots, the torque feedback from the right arm's servo motor will transmit directly to the control stick. Your wrist will feel like someone's hammering it. Over and over."

Han Zheng pulled his head back and flexed his right wrist.

"Team Leader Fang, I've fired a seventy-six-millimeter autocannon from a Dagger."

"The recoil of a seventy-six-millimeter autocannon is nothing compared to this." Fang Heping returned to the control console, his finger resting beside the firing button. "Don't compare equipment with me. Today, we're test-firing. You watch from behind the safety line."

At the far end of the firing range, the cockpit module of a retired Dagger had been welded onto a test rig, covered by a standard-thickness titanium alloy armor plate.

Lin Yuan stood behind the observation window in the control room. Sheng Lan stood to his right, and the high-speed camera on the terminal screen was already on standby.

"Fang Heping, are you ready?" Lin Yuan pressed the comm button.

"Ready. Single-shot mode, first round."

"Fire."

What erupted from the barrel wasn't flame.

It was a concentrated orange-red exhaust plume, igniting abruptly eighteen meters after the round left the barrel. Like a low-flying meteor trailing its tail, it smashed into the target platform.

The entire firing range shook.

Sheng Lan felt the tremor through the soles of her feet, while the water cup on the control room glass left a wavering trail of water.

The high-speed replay appeared three seconds later.

The round struck the surface of the armor plate and penetrated thirty-one millimeters. The rocket-assist stage continued another seven millimeters through the armor's inner layer before the delayed fuse triggered and the implosion chamber detonated.

The armor plate had not been penetrated.

But the inner wall of the cockpit module behind the target platform had shattered.

The console's sensor readings streamed across the display in dense rows: the stress peak produced by the shockwave along the armor's inner surface vastly exceeded the cockpit structure's tolerance limit; the seat's mounting bolts had snapped; the instrument panel had blown apart; the gel dummy simulating a human torso had completely deformed below the neck.

Fang Heping's voice came from the other end of the firing range, unnaturally flat.

"Director, the warhead didn't penetrate the armor."

"I saw it."

"But the cockpit module is totaled."

"I saw that too."

The firing range fell silent for two seconds.

Han Zheng's voice squeezed in from behind the safety line.

"Team Leader Fang, if this thing hits someone, what happens to the pilot inside?"

Fang Heping did not answer him.

Lin Yuan pressed the comm button.

"Automatic mode. Three-round burst. Fire at the second target."

The second target platform held a Phase Shift Armor simulation plate reconstructed from the Spark Data. Its thickness and material had been reproduced exactly according to GAT-X series specifications, with a battery pack beneath it to maintain its energy supply.

Fang Heping adjusted the barrel's aim, his finger hovering above the firing button.

"A three-round burst will stack the recoil peaks. I doubled the anchor bolts on the fixed support. It should hold."

"Fire."

Three muffled booms erupted in rapid succession, less than 0.4 seconds apart.

The first round struck the PS armor's surface. Its energy layer flickered, the round ricocheted away, and only a shallow crater remained.

The second impact landed two centimeters off, striking the edge of the same area. Visible ripples appeared in the PS armor's energy feedback.

The third struck squarely in the overlap of the first two impacts.

At that instant, the PS armor's energy layer flashed with a localized overload. The round embedded itself in the surface during that fraction-of-a-second gap, its rocket stage igniting and driving it twelve millimeters in.

Then it exploded.

The armor plate did not shatter, and the PS energy layer quickly recovered, but a stress fracture radiated outward from the center of the plate.

The battery reading dropped by fourteen percent.

Fang Heping stared at the data for a long time.

"A three-round burst can force PS armor to burn fourteen percent of its stored power. If we keep firing..."

"No need to calculate further." Lin Yuan's voice came down from the control room. "PS armor has limited stored power. As long as we maintain fire coverage, it will shut down on its own. Once it shuts down, it's just ordinary alloy."

"And then the fourth shot turns whoever's inside into paste." Fang Heping locked the firing button and slowly exhaled.

Han Zheng did not whistle again.

In the control room, Sheng Lan sent the frame analysis data from the high-speed footage to Lin Yuan's terminal.

"Director, the barrel temperature rises rapidly in automatic mode. After three shots, the chamber wall temperature is already close to the material warning limit. If it needs sustained output in combat, we'll need a cooling solution."

"Fang Heping will handle it. What else?"

Sheng Lan turned a page in her records.

"Regarding the ammunition belt, the interval between the second and third rounds was 0.7 seconds slower than the design value. The belt-link transmission mechanism in the feed box underwent slight displacement in a high-recoil environment."

Lin Yuan's gaze paused on the data.

"0.7 seconds."

"0.7 seconds. On the battlefield, that's enough time for a ZAFT Ginn to complete an evasive turn."

Lin Yuan closed the terminal.

"Notify Fang Heping. Redesign the ammunition belt transmission mechanism. Tighten the tolerance to within 0.1 millimeters. Before that, mount the Bombard Gun on Black Iron for a static weapon-handling test."

Sheng Lan made a note in her memorandum.

"What about Han Zheng's condition?"

"He's been asking when he can get in the cockpit."

"Tell him tomorrow."

Sheng Lan's pen paused.

"Director, Black Iron's right arm joint actuator hasn't been replaced with the reinforced version yet. Xu Yanqiu's report this morning stated that the gap between the Ceramic Steel armor add-on plates and the joint bearings is too large, causing uneven load distribution."

Lin Yuan walked toward the control room exit, one hand resting on the door handle.

"That's why we need to test it. If we don't put it in the cockpit, we'll never know where it'll crack."

The next morning.

Comprehensive testing ground, 811 Institute.

Han Zheng sat in the cockpit of the Black Iron Prototype, his right-hand control stick connected to the Bombard Gun, which was thicker than his entire arm.

The machine stood on a fixed support. Its power system was not activated; this was purely a static posture test.

He pulled the trigger.

One shot.

The barrel roared, and recoil traveled up the machine's right arm into its torso. The control stick in the cockpit jerked violently, numbing Han Zheng's wrist.

Two shots.

Three shots.

As the third round fired, the stress curve at the right arm's elbow joint suddenly spiked on the monitoring screen. A metallic shriek traveled through the machine's shell and into the cockpit.

"Cease fire!" Sheng Lan's voice exploded over the communications channel.

Han Zheng released the trigger.

Xu Yanqiu had already rushed to the edge of the testing ground, still wearing the goggles around his neck.

"Who approved a three-round burst before the right arm was upgraded?"

His voice could penetrate the soundproof walls.

"Which idiot designed this joint transmission system? The bearing housing's stress distribution doesn't account for lateral impact loads at all! Was this designed for serving tea, or for fighting a war?"

The two engineers from the structural team shrank into a corner. No one dared answer.

Lin Yuan stood beside the control console, the crack-propagation diagram for the right arm joint still flashing on the screen.

He was not looking at the cracks.

He was looking at another set of data.

The ammunition belt feed timing.

The interval from the first shot to the second was normal.

From the second shot to the third, the ammunition feed had been delayed by 0.7 seconds.

Exactly the same as yesterday.

He pressed the comm button.

"Fang Heping."

Fang Heping's panting came through the channel. He was recovering shell casings at the firing range.

"Here."

"The problem with the ammunition belt transmission isn't the tolerance."

Fang Heping stopped panting.

"What do you mean?"

"Your target-platform test yesterday and today's weapon-handling test on the machine both showed a 0.7-second delay in ammunition feed. The deviation was exactly identical. If it were a random malfunction caused by physical displacement in the transmission mechanism, the data from both tests shouldn't match this closely."

Silence came from Fang Heping's end.

"Check the electromagnetic release valve in the feed box." Lin Yuan rested a finger beside the 0.7 figure on the screen. "The valve's response curve may be developing a fixed delay at high temperatures."

The communication cut off.

Xu Yanqiu was still cursing in the testing ground, but his voice gradually shifted from rage into commanding roars as he began directing the structural team to dismantle the right arm joint for inspection.

Sheng Lan walked to Lin Yuan's side, her memorandum already turned to a new page.

"Director, the Pacific Fleet has updated its situation report."

Lin Yuan turned his head.

"The Atlantic Federation's Third Detachment crossed the median line four hours ago. They're now less than eighty nautical miles from East Asia's warning line. The vanguard consists of two Drake-class ships carrying an unknown number of Dagger MS units."

Lin Yuan shifted his gaze from Black Iron's damage data to the thin situation brief in Sheng Lan's hand.

"Speed?"

"Standard cruising speed. No acceleration."

"Formation?"

"A dispersed search formation. It doesn't look like they're preparing for a decisive battle. It looks more like they're searching for something."

Lin Yuan shut off the console screen.

"They aren't looking for something. They're measuring East Asia's response time."

Outside the testing ground, Xu Yanqiu's cursing still echoed.

Lin Yuan removed his communications headset and set it on the console.

"Sheng Lan, notify He Changying. Black Iron's right arm joint must be upgraded within forty-eight hours. Replace the ammunition belt feed valve at the same time."

Sheng Lan's pen stopped.

"Director, Black Iron's condition still can't be guaranteed to be fully intact after forty-eight hours."

"I know."

"What if they cross the line within those forty-eight hours?"

Lin Yuan picked up the headset and headed toward the testing ground.

"Then we'll fight with a half-finished machine."