Chapter 36: Bystander
“Sure enough, this should be error analysis and statistical model.
Manufacturing errors through statistical quantification of probability, simulating the influence of engine thrust deviation and environmental disturbances on trajectory.”
“This should be the dynamic trajectory correction equation set, limited by gyroscope drift and accelerometer noise in the inertial navigation system, to perform dynamic trajectory correction!
That’s right, the linear recursive least squares filtering simplified here, combined with the piecewise constant error model he provided, can effectively correct mid-section and terminal deviations in the ballistic trajectory.
And here, the conversion problem between Earth coordinate system, missile body coordinate system, and target coordinate system is simplified into matrix operation, used for generating guidance instructions.
In terminal guidance, predicting the landing point through angle vector projection not only increases precision now, but in the future, even when developing infrared guided missile, it can reduce the demand for real-time calculation.”
With the notebook for comparison, Qian Xuesen interpreted more information from the mathematical model in front of him.
The middle-aged man beside him keenly caught the sensitive word: “Infrared guided missile? Can it be used for infrared guided missile?”
It was no wonder the other party was so sensitive; the shadow left by the infrared guided missile on China was too profound.
The first combat application of infrared guided air-to-air missile was related to China.
The taste of being suppressed technologically was too unpleasant; everyone in China’s military industry technology lines still remembered it vividly.
“It cannot be used to manufacture infrared guided missile; it can be used to optimize infrared guided missile.
The biggest technology gap between us and America is in material processing.
I have communicated with comrades from Shanghai Electronics Institute, Shenyang Materials Institute, and Xi’an Engine Institute; the biggest reason for not starting the project in the past was that.
The Americans’ AIM-98 uses lead sulfide infrared photosensitive element; we don’t have high-purity lead sulfide single crystal growth process. If we use domestic lead sulfide probe, the sensitivity is at most 70% of theirs.
Their detection range is 8km; our theoretical detection range is only 5km.
Additionally, the missile seeker needs high-precision germanium lenses; we can’t mass-produce aspherical lenses with polishing degree reaching one-tenth of the wavelength at all, and can only rely on hand grinding, with yield rate not even reaching 5%.
Plus all-around backwardness in signal processing circuitry, solid propellant, missile body structure, etc., even if we spend time to make it, on one hand it’s already backward, on the other hand it cannot be used at all.
But now with angle vector projection landing point prediction, even if we have gaps, we can reach a usable level.
In other words, in the past we made it but couldn’t hit the opponent when launched, while based on angle vector projection landing point prediction, at least there is probability to hit the opponent.
In the future, if technologies in materials, circuitry, photosensitive elements, etc., catch up, we can even achieve more precision than their Sidewinder!”
Three hours passed in the blink of an eye, darkness gradually receded, and the East was bright.
However, for the Chinese side, there was too much preparation to do.
After confirming that the model transmitted back by Lin Ran was greatly beneficial to all aspects, the vast machine began to operate at an unprecedented speed.
Qian Xuesen didn’t even have time to rest and was directly arranged to take a special plane for an emergency trip to Harbin to comprehensively upgrade the DF-1 missile using the existing model.
The latest news from the south would be synchronized to him immediately via telegraph.
According to his estimate, optimizing DF-1 with the model given by Lin Ran could at least improve DF-1’s precision to within 1 kilometer range.
Not to mention whether it could be used, this was already international top level, capable of export for foreign exchange earnings.
Once verified successful, it would also be a direct slap in the face to the departing Russian experts.
Besides Qian Xuesen, Hua Luogeng was also urgently transferred to a new unit.
Because the models understood by Qian Xuesen were all interpreted by Chen Jingrun and converted into language he could understand, while a large number of models were still hidden in obscure mathematical language, urgently needing mathematicians to interpret them.
In just one night, Chen Jingrun had finished interpreting all the easy ones; the remaining were tough nuts.
“Academician Hua, your work needs some changes; the time to reunite with family may become very little. Are you willing to participate?”
Hua Luogeng was also shrewd and immediately guessed the reason.
“If the country needs it, I will not hesitate.”
Hong Kong, Modern Stage.
“Madam Meng, Professor Lin is at the door.” Nanny Sister Liu walked into Meng Xiaodong’s room and said softly.
Meng Xiaodong was a famous Peking Opera actor, known as “Winter Emperor,” and was now living in seclusion in Hong Kong, not performing on stage for a long time.
Not performing on stage didn’t mean not caring about current affairs; she was naturally very curious about this character who stirred up waves in Hong Kong this summer.
Simply from the newspaper, the other party was young, handsome, and brilliantly talented; Hong Kong media praised him to the skies, calling him a mathematics genius that appears once every few hundred years.
She was more curious about what the other party wanted from her.
Three years ago, Zhang Shizhao came to persuade her to go back; in her view, her remaining value was just to go back to teach, but Professor Lin was an American professor—could he be persuading her to go to America?
Another possibility was that the other party was her play fan and wanted to meet her.
But this possibility combined with the other’s pitifully young age seemed unlikely.
However, Meng Xiaodong did not refuse the other party’s visiting card and was even quite expectant of the intention of such a talent seeking her.
“Professor Lin truly lives up to his reputation; not only is his appearance impressive, but his temperament is that of a typical scholar.” Meng Xiaodong complimented.
“Thank you for the compliment, Miss Meng. I came this time hoping you can help me record a short song.” Lin Ran took out a sheet music from his suit pocket and handed it to her.
This intention was indeed something she hadn’t thought of. Meng Xiaodong picked up the sheet music; besides the neat handwriting, the title caught her eye:
“Bystander?”
After reading it, she tried singing a short segment:
“.
This trip to the feast of joy covered in dust
Youth fades, how unseen
Cave paintings brilliant in the past
Yet wake to be a bystander
“
One thing impossible to avoid when coming to Hong Kong is accepting interviews; more accurately, Lin Ran also needed to accept interviews, and this Bystander was the song carefully selected for the interview.
As soon as you come to Hong Kong, the other side produces a world-class short-range missile; maybe nothing now, but after Lin Ran stirs up waves in the American aerospace circle, some departments and some people digging it out to make an article would be strange if not.
One Bystander is certainly useless; the most needed is to cooperate with General Electric to win the NASA order, proving his indispensability, with Morgan family and Professor Horkheimer’s Rockefeller family behind him jointly protecting him.
But others protecting him also needs a public statement; Bystander is the song he prepared to express his stance.
The other one handed to the Chinese side is Me and My Motherland.
After Meng Xiaodong finished singing, she applauded repeatedly, the applause lightly echoing in the living room:
“Good song, good tune, good flavor, good metaphor. Unfortunately, Professor Lin found the wrong person; I am Kun Sheng, not Dan Jiao.”
