Republic of China: Ace Pilot

Chapter 643 Supernatural Processing: Millimeter-Level Precision "Handcrafted Intelligence," Taishan Guided Rocket Test Launch

Inside the rocket factory, the roar of machines filled the air as skilled workers produced parts for 1200 heavy-duty bicycles.

However, the temporary workshop on the east side of the factory area was rather quiet.

Only Fang Wen and a few veteran lathe operators were working there.

He stood beside the C6140 lathe, his hands lightly gripping the operating handles. His mechanical perception ability, like a fine net, encompassed every detail of the lathe spindle, the cutting tools, and the alloy billet.

But this is not enough to achieve the desired precision.

He absorbed the energy from the treasure, amplifying his mechanical perception combined with his clairvoyant abilities.

The orientation of the metal grains inside the billet, the minute wear of the cutting edge of the tool, and the radial runout of 0.02 mm when the spindle rotates are all clearly presented in his perception.

At this moment, he is processing the core component of the guidance device—the magnetron anode.

The core function of the magnetron anode is to "build a high-frequency resonant cavity". Through a cavity of a specific shape, it is combined with the cathode to generate a microwave signal of about 3 GHz for radar illumination.

This process has three requirements for the material: high electrical conductivity, strong thermal conductivity, and ease of processing.

The suitable material is high-purity copper.

The copper blank in front of Fang Wen needs to be cut into a cylindrical shape with an inner diameter of 12.7 mm and a wall thickness of 1.5 mm. The inner wall finish needs to reach Ra0.8μm (▽7), which is the smoothness of the inner wall of the pressure cooker.

In 1939, without CNC equipment, this was almost impossible for ordinary skilled workers to achieve with machine tools.

Besides Fang Wen.

He began operating the machine, adjusting the lathe feed rate in real time using his special ability. When he sensed a sudden increase in the cutting force of the tool, which indicated a change in grain density, he immediately reduced the feed rate from 0.1 mm/r to 0.05 mm/r.

Under his guidance, the blanks were gradually transformed into the shape required by the design.

I had just finished making an important component when my workers arrived.

"Mr. Fang, the meshing clearance of these gears is always a bit off, and they'll get stuck after assembly," an experienced machinist reported with a worried expression, holding a blank bevel gear for a servo motor.

Fang Wen took the blank and placed it on the testing tool, using his special ability to instantly "scan" out the tooth profile error.

The tip circle of three of the teeth is 0.04 mm larger than the design value.

Instead of changing the blank, he fixed it to the dividing head, held a fine file, and precisely filed away the tiny excess material using the "error rate" he sensed with his special ability.

"Try it and see." He handed the gear to the old machinist.

When the gear was reinstalled into the servo, it turned without any more jamming. The veteran machinist took a feeler gauge to measure it, and the clearance was exactly what was required by the design. He couldn't help but exclaim, "The general manager is amazing! This craftsmanship is even better than the parts made by foreign precision equipment!"

Fang Wen smiled and continued processing.

This scene lasted for ten days.

From the LC tuning coil of the radar receiver to the blades of the gas turbine and the spring gear of the mechanical integrator, he personally crafted every key component.

Fang Wen also noted down the specifications and production process of these parts, so that they could be used as production process standards once the prototype missile was finalized.

Time passed slowly, and the first batch of parts was produced under Fang Wen's supervision and delivered to the research institute.

Jiang Wenjin and the researchers repeatedly measured with micrometers, and were just as surprised as the workers. In the absence of the best high-precision manufacturing equipment, the general manager had actually led Taishan Military Industry's own technical workers to produce all the high-precision equipment parts.

Subsequently, the research institute's guidance team began assembling the prototype missile.

Time flies, and a month and a half passes quickly.

The 1200 heavy-duty bicycles supplied to the Eighth Route Army have all been assembled and transported to China in two batches.

The prototype of Taishan's first guided rocket has also been successfully developed.

January 5, 1940, firing range outside the base in northern Burma.

In the center of the firing range, an empty shell of a Taishan military vehicle was used as the target, with red markers placed 50 meters and 100 meters away to mark the deviation of the bullet impact point.

Meanwhile, on the other side of the runway, Fang Wenzheng and Gong Xiuneng were loading three prototype guided rockets, painted silver-gray, into the rocket launch pod.

The new version of the guided rocket is named 'Taishan Guided Test Type 1', with a diameter of 88 mm.

Compared to the previous Soviet-made 82mm model, it has an increased diameter of 6mm.

To this end, the rocket launchers were also modified, changing from the original 10-cell launchers to 6-cell launchers.

After loading the new experimental air-to-ground rocket, Fang Wen boarded the plane, sat down, started the engine, and merged with the aircraft using his mechanical perception ability.

The aircraft is in good condition, the modified illumination radar mounted under the wings is functioning normally, and no problems were found with the rocket launchers.

He picked up the microphone: "Calling the launch team, we can begin now."

He then piloted the Qinyuan into the air; Jiang Wenjin observed from the ground through a telescope, while the technician beside him kept a close eye on the signal receiver.

The aircraft circled in the air around the target.

To ensure the experiment's success, Fang Wen injected energy into his body, gaining a brief 'supernatural state'.

In that omnipotent state, he had an intimate knowledge of the aircraft's interior, even down to the microscopic level.

The radar inside the cabin: The magnetron pulses at a frequency of 1000Hz, and the electromagnetic waves of 3GHz are focused into a narrow beam of 2° by the parabolic antenna, like an invisible beam of light, steadily covering the target 1500 meters below.

The three frequency codes are 1200kHz, 1500kHz, and 1800kHz, which perfectly match the channel pre-tuned by the rocket receiver.

After adjusting the firing direction, he pressed the fire button.

The moment the rocket left the launch pad, Fang Wen's senses penetrated the rocket's outer shell.

He "saw" the spoiler at the tail nozzle precisely return to zero, the gyroscope spindle rotate at high speed, and the 24V voltage output from the silver-zinc battery flow into the receiver along the wire.

The quad-arm antenna captures the echo reflected from the target. The 3GHz high-frequency signal flows into the mixer, collides with the signal of the local oscillator coil, and is converted into a 455kHz intermediate frequency signal.

Just as the rocket reached 800 meters, Fang Wen's senses suddenly detected an anomaly: the copper surface of the vacuum tube anode turned dark red, and the temperature value climbed in his senses like water flowing—180℃, 220℃, 280℃, getting closer and closer to the copper's softening critical point of 300℃.

The amplifier's gain began to plummet, dropping from 60dB to 35dB, and the intermediate frequency signal became weaker and weaker, like a flame being submerged by a tide.

The metal pendulum in the pendulum error detector, which should have swung with the target deviation, was frozen in place, and the output error voltage dropped from 2.5V to 0.8V.

Failed.

Fang Wen sighed inwardly. Then, he "saw" the rocket's spoiler lose signal control, veer erratically by 1°, and the projectile suddenly veered to the left, eventually plunging into the grass at the edge of the firing range, raising a cloud of dust.

The failure of this prototype missile made Fang Wen realize that the next two were unlikely to succeed.

He immediately landed, unloaded the two prototype missiles, and loaded them onto the Taishan military vehicle.

Jiang Wenjin, who had rushed over, asked in confusion, "Why only fire one?"

"I've discovered a major problem that needs to be addressed. I'll continue tomorrow."

After Fang Wen finished speaking, he jumped into the military vehicle and drove straight back to the base.

Inside the laboratory, Fang Wen and the researchers from the guidance team were discussing.

"After the prototype missile is launched, the anode temperature will rise rapidly, exceeding 300°C. Under these conditions, the copper material will be affected, causing the entire active radar seeker to fail."

After he pointed out the problem, the researchers immediately conducted an experiment.

In simulation mode, the signal does indeed fail as the temperature rises.

In response, one researcher suggested: "To solve this problem, I think the best approach is to add heat sinks and use airflow to force cooling, which will not alter the structure of the prototype missile."

This suggestion is very reasonable, and everyone tends to solve this problem by adding heat sinks.

However, the specific implementation will be handled by Fang Wen.

After all, only he could complete the modification in the shortest amount of time.

Immediately afterward, the meeting ended, and Fang Wen began his presentation.

On the lab bench, he placed the copper anode component on a vise, his fingertips touching the metal surface to activate mechanical sensing.

The flatness error of the anode outer wall, the welding position of the vacuum tube pins, and the reserved installation space inside the projectile instantly formed a three-dimensional model in his mind.

“Use aluminum fins, 1.2 mm thick, to make 12 ring-shaped fins, spaced 3 mm apart, and attach them radially to the outer wall of the anode.”

He picked up a pencil and sketched on the drawing paper, the tip of the pencil precisely outlining the contours of the fins, muttering to himself.

"Aluminum is lighter than copper and has a thermal conductivity of 237 W/(mK), which is sufficient to conduct heat away from the anode without adding too much weight to the projectile."

Fang Wen himself designed this.

In just two hours, he made a heatsink that met his design requirements.

Subsequently, the anode, now fitted with heat sinks, was inserted into the second prototype missile. Fang Wen stood the missile upright and observed its interior using his X-ray vision: 12 aluminum fins, like open umbrella ribs, were tightly attached to the copper anode, with graphite media evenly filling the gaps, neither obstructing the vacuum tube pins nor touching the radar antenna feed line.

But that's not all.

"Then, make four 10-millimeter ventilation holes on the side wall of the missile body to allow high-speed airflow to pass through the gaps between the fins." Fang Wen pointed to the middle of the missile body and explained his subsequent design. "The holes should be positioned to avoid the servo linkage and tilted at a 15° angle to prevent rainwater from entering."

As Jiang Wenjin calculated, he analyzed, "Based on the rocket's flight speed of 340 meters per second, the airflow velocity when passing through the ventilation hole can reach 50 meters per second. The heat dissipation area of ​​the fins is 0.08 square meters, which theoretically can control the anode temperature below 220°C."

Fang Wen added, "If the edges are too sharp, they will create airflow vortices, which will actually affect heat dissipation. Grinding the openings into rounded corners with a radius of 1 millimeter allows the airflow to pass through the fins more smoothly."

"Really?" Jiang Wenjin wasn't sure. As a scientific researcher, he couldn't understand Fang Wen's amazing ability to acquire knowledge and could only prove it through practical results.

One day later, the modified 'Taishan Guidance Test Type II' began test firing.

Fang Wen piloted the fighter jet into the air, and launched it after completing radar lock-on.

The rocket was launched from the launch pod and hurtled toward the target at high speed.

The instant the rocket left the launch site, Fang Wen's mechanical senses, like a fine probe, instantly pierced through the silver-gray body, bringing every subtle change inside into view.

The initial velocity of 340 m/s caused the heat generated by the friction between the projectile surface and the air to be conducted along the outer shell, but his attention was entirely on the 12 aluminum fins.

The airflow was flowing in through the 15° inclined ventilation holes on the side wall of the projectile. The rounded edges indeed eliminated the vortex. The 60 m/s airflow was like an invisible brush, quickly sweeping across the gaps between the fins.

He "saw" the temperature rise curve on the outer wall of the copper anode suddenly slow down: 160℃, 190℃, 210℃, and then steadily stop at 215℃, with a safety margin of 85℃ before the softening critical point of 300℃.

The high thermal conductivity of aluminum successfully saved the guidance equipment; the dark red luster of the anode gradually faded, restoring the bright copper color of the metal itself.

"The gain is stable at 55dB!" Fang Wen's perception detected the signal fluctuation of the vacuum tube amplifier—the 455kHz intermediate frequency signal oscillated clearly in the detector like a smooth sine curve, with no more signs of attenuation as before.

The metal pendulum in the pendulum error detector finally came to life, swinging gently with the slight azimuth shift of the target: when the projectile deviated 0.5° to the right due to airflow disturbance, the pendulum immediately shifted 2mm to the left, and the output error voltage stabilized at 2.3V, which was accurately transmitted to the tail fin control unit through the wire.

The four spoilers at the tail nozzle then move – the two on the right deflect inward by 1.2°, while the two on the left remain in place, instantly changing the direction of the exhaust flow. The resulting lateral control force gently "turns" the projectile back to its intended trajectory.

Fang Wen's perception extended along the servo linkage. The gap between the bevel gears during engagement was always controlled at 0.15mm. Although there were no advanced lubricating materials like those in the future to cause some wear and tear due to metal-to-metal friction, this was, after all, a consumable weapon, so it didn't matter.

At this moment, the radar beam was still firmly locked onto the empty hull of the military vehicle 1500 meters away. The 3GHz electromagnetic wave was reflected off the target surface and then steadily captured by the four-armed spiral antenna on the head of the projectile.

Fang Wen "saw" the LC tuning coil inside the receiver vibrating slightly. The deviation between the local oscillator frequency and the echo signal was always controlled within 50kHz. The synchronization signal output by the phase detector made the entire guidance link operate like tightly meshed gears, one link after another.

When the rocket reached 1200 meters, a sudden crosswind caused a brief jump in the target echo, and the output voltage of the pendulum error detector instantly dropped to 1.8V.

However, the correction signal from the gyroscope was quickly added in, and the inertial force generated by the high-speed rotation of the main shaft instantly canceled out the attitude disturbance caused by the crosswind. The error voltage quickly rose back to 2.2V, the spoiler was finely adjusted by 0.8°, and the trajectory of the projectile once again coincided with the center of the beam.

There are only 500 meters left.

Everyone was excitedly awaiting the results.

In his 'supernatural state,' Fang Wen's perception detaches from his subject, allowing him to 'touch' the target ahead of time.

He could clearly distinguish the thickness of the sheet metal in the empty shell of the military vehicle and the metal seams of the window frame.

It can also observe the internal situation of the rocket at the same time.

When the distance to the target is 100 meters, the pendulum error detector outputs the final correction signal, and the spoiler deflects synchronously by 1° to finally calibrate the projectile's attitude.

At this point, the anode temperature remained stable at 218℃, the amplifier gain was 54dB, and all parameters were within the design range.

"boom!"

In the instant the smoke rose, Fang Wen's perception froze at the last moment before the impact: the rocket, traveling at 335 meters per second, struck the rear of the military vehicle's empty shell. The warhead detonated the moment it hit the ground, and the shockwave twisted and deformed the metal of the target not far away. The shrapnel flew over the entire target.

Even though he already knew the result, Fang Wen still picked up the phone and asked, "How did it go?"

Jiang Wenjin's excited voice came through the radio: "The hit point deviation is only 3.2 meters! President Fang, we've succeeded!"

(End of this chapter)