I started with a ship full of max-level veterans, and I'm just a complete noob.

The red pen cap fell into the whiteboard slot with a soft click.

The major general had already stood on the other side of the whiteboard, spreading out the newly delivered gyroscope test sheets one by one, and then using a wooden ruler to press down the rolled-up corners of the paper.

"Since we're going to start with equations, let me first complete the engineering conditions. This batch of data comes from three types of free gyroscopes, including temperature drift, installation angle, and initial alignment error."

The wooden ruler slowly moves down the table, and dozens of deviation values ​​accumulate step by step with the flight time, eventually corresponding to the edge of the missile's range.

"The onboard gyroscope is responsible for stabilizing the platform, the integrator outputs attitude corrections, and the radio only provides ground assistance. The Aksai-style direction finding and suppression experience has limited applicability here."

The major general stopped the wooden ruler at the point where it landed.

"If you think there's something wrong with the preparatory team's approach, find the evidence in this set of data. Don't use one battle to represent the entire experiment."

Jiang Ming did not immediately put pen to paper. After reading the initial drift of the gyroscope, he matched the calculation table with the horizontal motion equations on the whiteboard one by one, keeping the red pen in his hand the whole time.

The data itself is self-consistent, and the test conditions, installation deviations, and integration errors all have their sources. The real gap is hidden in the model boundary. Continuing to calculate along the existing path will only yield more accurate but incorrect results.

The major general waited a moment, and seeing that he still hadn't spoken, he picked up a pencil and added a set of extreme temperature drift data.

"During the flight of the projectile, the gyro drift will be amplified through integration. The error of a single error can be corrected, but after multiple errors are superimposed, the standard ballistic table must be used to converge the trajectory."

"The Soviet-made R-2 already had mature firing tables. During the preparation stage, we should thoroughly understand the standards before discussing modifications. This is in line with the engineering process."

Jiang Ming raised the red pen and dropped it from the upper left of the whiteboard, slanting it across all the error propagation paths listed by the Major General, separating the fixed latitude condition from the terminal correction term.

A red line runs across the center of the black equation, and the sound of pages turning on the conference table immediately stops.

He pointed the red pen to the truncated Earth rotation term, his tone now consisting solely of a statement of the calculation conditions.

"The lateral guidance tolerance of the Soviet-made R-2 missile has a 2 percent drift in low-latitude regions. With your algorithm, the missile simply cannot hit the target area."

A returning expert took off his glasses and wiped the lenses, while the person next to him shook his head and turned to the horizontal correction section of the original Russian document.

The major general put down the wooden ruler, his face showing even more doubt.

"Where does the two percent come from?"

"The latitude of the Soviet test range, the latitude of the planned test area in China, the Coriolis term, and the aerodynamic sideslip coupling can all be seen by integrating these four terms into the same set of integrals."

Jiang Ming wrote down the latitude difference in the blank space on the whiteboard, changed the fixed parameters in the standard trajectory to variables, and then substituted the flight time and lateral velocity components.

"Current simulations treat Earth rotation correction as an independent additional factor, while gyro drift is handled within the stable platform. After the missile is disturbed by crosswinds and angle of attack, the two will recouple in the lateral channel."

"When the original radiation table was used, this part was treated as random scattering absorption. When it was moved to a lower latitude region, the deviation direction began to have persistence, and the terminal correction will continue to follow the erroneous reference."

He wrote down the first set of approximate results, and then replaced the standard atmospheric conditions with the upper-level wind parameters from the Aksai record. The lateral deviation increased rapidly with the range.

The expert sitting on the right was initially leaning back in his chair, but after seeing the second set of integrals, he moved his body toward the edge of the table and pulled out his slide rule.

"Wait a minute, you've included the angle of attack change caused by crosswinds into the attitude channel here, but the standard R-2 model only takes the average aerodynamic coefficients."

"The mean coefficient is applicable to a given projectile and given atmospheric conditions. Domestic materials, processing errors, and wind layers in the test area will all change the actual partial derivative. If we continue to lock it as a constant, the firing table will cover up the problems of the equipment."

Another expert in automatic control copied the coupling terms written by Jiang Ming onto the manuscript paper, recalculated the symbols, and then looked up at the major general.

"The symbol is valid, but the value still needs to be verified. However, this coupling path has indeed been broken up."

The major general took the slide rule and rechecked the latitude and flight time.

"Even if it is true in 2% of cases, it only proves that the firing table needs to be revised, but it cannot lead to a new guidance network."

"Therefore, the red line is only responsible for cutting off the old arguments; the change of clothes starts from here."

Jiang Ming turned to the right half of the whiteboard, wrote the unsteady boundary layer problem in von Kármán's letter as an aerodynamic disturbance inlet, and spread the draft reply he had completed on the way out onto the table.

He can only use the parts he has already derived; the sealed academic system is still separated by the other side of the gray layer, and any missing link must be filled in by existing knowledge.

Boundary layer theory does not directly control the ballistic trajectory here. It describes how surface disturbances on the projectile change local pressure and then projects the pressure deviations into the attitude and lateral acceleration channels.

Jiang Ming wrote down a three-layer model along the aerodynamic disturbance inlet. The first layer received data from the gyroscope and integrator, the second layer received ground measurement results, and the third layer adjusted and corrected the weights according to the flight segment.

"Due to the limitations of weight, power consumption, and device lifespan, the missile's onboard systems cannot cram all the calculations into the missile, and ground control cannot wait for deviations to accumulate before issuing correction commands."

"The aerodynamic model is made into a compensation framework that changes with the flight segment. The ground station updates the deviation based on radar angle and velocity measurements, and the missile only performs the selected corrections."

The major general looked at the three-layer structure and lowered the wooden ruler back to the radio calibration column.

"How does the ground station distinguish between aerodynamic disturbances and gyro drift, since the two are often reflected in the same attitude data?"

Jiang Ming drew two curves with different time scales next to the model.

"Gyroscope drift accumulates slowly, and aerodynamic disturbances are related to atmospheric structure, projectile angle of attack, and velocity range. As long as the measurement frequency is sufficient, the two channels can be separated using time characteristics."

He retrieved the internal summary of the Aksai K-band fragments. The original drawings were still being transported in a secure vehicle. The conference room could only view the numbered and extracted frequency bands and pulse characteristics.

"The 24 gigahertz equipment in the mine reminded me that the higher the frequency, the narrower the beam and the stronger the angle resolution. At present, China cannot produce a complete missile-borne K-band guidance system, but the ground measurement chain can first study the high-frequency band to supplement the channel."

"The low-frequency radar is responsible for continuous tracking, while the high-frequency narrow beam is responsible for verification of key sections. By sending the two sets of data into the aerodynamic compensation model, the error correction caused by a single measurement error can be reduced."

The returning expert, who had been shaking his head, had left his seat, stood to the side of the whiteboard with a slide rule in hand, and moved his gaze back and forth between the two time scales.

"If the high-frequency band is only activated in the mid-range, the pressure on rain attenuation and equipment lifespan will decrease, and the missile will only need to retain the receiving and execution interfaces."

Another person grabbed a black pen from the whiteboard tray and added the ground station delay next to Jiang Ming's model.

"Communication delays must be taken into account; otherwise, by the time the correction reaches the projectile, the aerodynamic state has already changed."

Jiang Ming incorporates the delay term into the state prediction, advances the current measurement value to the expected arrival time of the instruction, and then uses interval weights to limit overcorrection.

"The ground station should send the correction amount under the predicted state. After entering the terminal phase, the weight of external commands should be gradually reduced, allowing the missile's onboard stabilization system to take over the remaining errors."

The experts who had been sitting around the long table awaiting the conclusion were now all gathered around the whiteboard, with draft paper under their arms, continuously verifying the measurement accuracy, communication delay, and the onboard actuator.

The doubts have not disappeared, but have shifted from whether Jiang Ming is qualified to participate to how much equipment the model needs and which parameters are required for the first simulation.

The major general pulled out two pages of his gyroscope data and pasted them directly below the whiteboard.

"Use the temperature drift curve of the second type of gyroscope to see if the predictor will misjudge the platform error as aerodynamic sideslip."

Jiang Ming reorganized the state variables, added a slow change constraint before the gyroscope drift term, and wrote the observation matrix of the high-frequency measurement channel next to it.

Qian Xuesen remained seated at the end of the long table, neither shielding his students from questions nor announcing the conclusions beforehand. He only opened the draft of his reply when Jiang Ming introduced the boundary layer perturbation model.

Seeing that the derivation of the second problem corresponded to the whiteboard structure, he picked up his Parker pen and marked two engineering conditions that needed to be added on the edge of the draft page.

With less and less space remaining on the whiteboard, Jiang Ming placed the last set of parameters in the lower right corner, providing the initial compensation range under low-latitude test conditions.

The sound of the slide rule sliding came from behind. The expert who shook his head first had already calculated the result twice, and then wrote "to be verified by actual measurement" next to two percent with a black pen.

"If this framework can run, the original interface division of the guidance group will have to be completely redone."

The major general looked at the old equations that were cut off by the red line and reached out to take down the original derivation table pasted next to it.

"Don't talk about redoing it yet. Let's list all the simulation conditions tonight, and decide who's responsible for which part..."

The conference room door was pushed open at that moment, the door panel slammed against the limit switch, and Director Wang strode in, soaked to the bone, his face ashen, clutching a briefing that had just been delivered from the interrogation point.