After nearly a week of assembly and testing, Roland and Anna successfully developed the bomb's contact fuze.
Unlike a cannon's fuze, it avoids both extreme heat and pressure and the high G-force impact of firing, making its structure remarkably simple. Yet even this basic mechanism—just a firing pin and a spring—required two people to test it countless times before succeeding.
The core issue is that no one knows the precise spring tension required to prevent accidental firing during accidental drops, while maintaining stable pin contact for reliable ignition during normal throws.
He and Anna could only test it bit by bit by adjusting the spring's thickness and stiffness.
Fortunately, the latter had done extensive preliminary work with Lucia on a daily basis, allowing Roland to access an increasing supply of high-quality materials. The final test proved successful with Alloy Steel No.1365, which boasts high hardness and low toughness. Even if dropped from a height of one meter, the bomb would not be completely crushed.
Once the right spring was chosen, the rest fell into place. Even without seeing a real fuze, Roland could design one based on its working principle.
Definitely outdated, but for the clunky, bulky air bomb, it's still good enough.
The completed version of the touch fuse is a cylindrical object, 12 cm long and 5 cm in diameter, with threads at the bottom that can be screwed into the opening at the top of the bomb.
Its interior features a concave groove with a convex protrusion, designed to precisely fit the striker. Under normal operation, a spring pushes the upper section against the groove's edge, allowing the striker to drop into the groove at a distance of exactly one finger from the primer. For added safety, Roland added an extra hole at the striker's tip, secured by a pin that must be removed before firing to enable the striker's vertical movement.
The simulated test was carried out on a sunny afternoon.
Since the bomb weighed nearly five nightingales after being loaded with gravel and black powder, Roland chose not to board the hot air balloon. Instead, he observed the target site from a lookout 300 meters away.
In addition to him, the trial run was also attended by Iron Axe, commander of the First Army, and Chief Knight Carter Lannis.
"You're planning to drop a massive explosive package into the royal palace using a hot air balloon?" Carter found it hard to believe his ears after hearing Roland's plan. Launching an attack from 2,000 meters above the ground, disregarding the walls and defenses—this completely overturned his combat philosophy. Of course, during his year in Border Town, he'd already been turned upside down many times.
"Under proper control, this is achievable," Roland nodded. "Tefiko is forcibly recruiting new militia. If we fail to stop him, the Western Frontier will inevitably face another assault by the drug-fueled troops. Even if we win, it won't bring us any advantage." The secret letter from Tasa revealed that Tefiko still intended to exhaust his resources through his usual tactics, and it remained uncertain whether Barov's envoy team could secure more recruits for Border Town before the enemy's advance.
"If you could truly unleash the wrath of the thunderbolt upon Tifeco's head, he'd be utterly terrified!" the Iron Axe exclaimed with excitement. "This is an unstoppable divine punishment!" "I hope so," Roland said with a smile.
Although Tasa noted in the letter that Tifecko had likely deciphered the formula for black powder and set up workshops in the inner city to mass-produce this dangerous substance, after careful deliberation, he ultimately chose the palace as his target.
The reason is simple: the palace is conspicuous enough.
From a height of two thousand meters, even the grandest city of Graycastle appears no larger than half a palm. This makes pinpointing the exact drop point crucial for bombing. The royal palace, situated at the heart of the inner city, is encircled by red-tiled walls and crowned with pristine white stone slabs. Its striking silhouette during the fall makes it virtually impossible to miss.
But the workshop is different.
With no floor plan of the capital city at hand and no one to guide him, describing the target's location verbally proved challenging. Given the workshop's limited size, if the bomb missed and landed in a civilian house, the plan would backfire.
Suddenly, a white shadow plunged to the ground, sending a column of smoke billowing across the test site, followed by a muffled thud.
"The bomb seems to have landed," Roland said, folding the scope. "Let's see how it goes." After a week of training, Lightning's bombing skills had improved remarkably. The aerial bomb landed within five meters of the target center, its fuselage completely buried in the soil, and the shell was severely deformed from the impact.
When the Voyager touched down, Anna defused the bomb with black powder. Everyone saw the soil near the fuze had turned a charred black—proof that the high-temperature gas from the primer ignited the black powder on the ground, and the fuze was functioning properly. Had the projectile been loaded with nitrate starch, it could have easily created a crater four to six meters deep, killing exposed personnel within a fifty-meter radius.
Now that the air bomb has been developed, the next step is to finalize the combat plan.
Roland scanned the crowd before speaking slowly, "The surprise attack on the capital will take place next Monday. First, Iron Axe, you lead a fifty-man musket unit to escort the Witch to the outskirts of Silverlight City. There's a mountainous area that can block the view, perfect for setting up camp or releasing balloons." "Understood, Your Highness!" Iron Axe replied.
"Don't we fly directly from Border Town?" Wendy asked.
"No, that's too far," Roland shook his head. The journey from the Western Frontier to the capital would take at least a week, and even with the Voyager's direct flight, it would still require about three days—making the total trip six days round trip. The suspended platform, equipped with a launch rack, could only carry two people, and Nightingale couldn't join them. Among the four Witches, only Anna possessed combat skills. Spending six nights in the wild was too risky for him to accept. "If we depart from Silverlight City, you'll complete the bombing in just one day and return before sunset." "Next up are the Witches. This mission includes Anna, Wendy, Lightning, Maxie, Nightingale, and Sylvie. The last two will monitor the camp's surroundings, while the first four will execute the attack as trained—especially Lightning," he said, looking at the young girl. "Success depends on you." "Leave it to me," she replied, patsing her chest.
"Finally, I must emphasize safety," Roland said emphatically. "I'll be waiting for you in Border Town." Four days later, the first bomb,' Dongfeng-1,' was loaded onto a carriage and escorted by the First Army to a cargo ship bound for Silverlight City.