Back in 1978, I was admitted to Northwestern Polytechnical University.

Chapter 281 The Red Arrow 8 was also developed in Chang'an!

Chang'an, Institute 203.

As dawn breaks in the east, it's another...day of hard work!
A middle-aged man looked up, glanced out the window, and then shook his head helplessly: "It seems this experiment has failed again. Let's go back and rest for a day. We'll think of another way tomorrow!"

“President Wang, this can’t go on like this. Should we… ask our sister companies for help?” Engineer Yuan Hongjun asked.

“Yes, Mr. Wang, I think we should ask Northwestern Polytechnical University for help. It’s not shameful!” Engineer Luo Yu said.

Chief Engineer Wang Xing took a deep breath: "Of course it's not shameful. Northwestern Polytechnical University is now a leader in scientific research. Many factories and research institutes are seeking cooperation with them. In the field of missiles, they even have their own factory. However, they also undertake a lot of tasks!"

Wang Xing looked at everyone and said, "Everyone, Northwestern Polytechnical University is a place that does big things. They have so many research and development projects that they can't keep up. But our Institute 203 is just working on this small anti-tank missile. How can we trouble them? It would be a disgrace for us to waste their precious research and development time!"

Northwestern Polytechnical University has too many projects, especially recently, it has also taken on the Navy's ship-to-air missile research and development project, and they are already very busy there! They are doing big projects!
What about us?
Less than a meter long, only 120 millimeters in diameter, and weighing just over ten kilograms, such a small missile is simply not presentable. Using such a missile to delay Northwestern Polytechnical University's research and development time... Wang Xing felt he had no shame in doing so.

He walked to the window and looked at the rising sun in the east, shining on Chang'an. There were too many research and development units here. Institute 203 was so small that it was almost invisible.

Wait, why is a car driving into the compound? Who is this person?

Wang Xing looked down and saw several people getting out of the car. One of them was Director Li of Institute 203. Next to him were two young people, a man and a woman. The man was... Qin Liang?
Qin Liang is absolutely a household name in Chang'an and in the domestic scientific research field. I never expected that he would come to our Institute 203.
At this moment, Director Li was enthusiastically introducing things to Qin Liang.

"Our Institute 203 was established in 1956, mainly engaged in defense science and technology research. Externally, we are known as the Shaanxi Qinghua Electromechanical Research Institute. We have many research directions, including aircraft design and control, optoelectronic technology, aerodynamics, etc. Many of our researchers are graduates of Northwestern Polytechnical University. The HJ-8 missile is also under our institute's research, and it is being overseen by Lao Wang..."

"There are quite a few research institutes in Chang'an!" Qin Liang remarked.

Although he has been here for more than three years, Qin Liang's understanding of Chang'an is still very limited. He has had more contact with the aviation department and knows about the flight test institute, but he really doesn't know about the weapons system.

Institutes 203, 204, 206, 210... all have their headquarters or R&D centers here! There are quite a few others, such as 212, 504, 706, and if you count them all, there are probably more than twenty.
What surprised him most was that although the production of the HJ-8 missile was carried out in a factory in the south, its research and development was carried out by the 205 Research Institute under the Ordnance Industry!

What is the current status of the development of the HJ-8 missile?

"Well... wait for Lao Wang to report to you... Oh, Lao Wang is already down!"

Amidst the clattering footsteps, Director Li saw a large group of people coming down. Old Wang walked at the very front, his steps quick. Although he said he was afraid of troubling Qin Liang, he had to welcome Qin Liang since he was here!
"Comrade Qin Liang, welcome to Institute 203. You can just call me Lao Wang!"

"Hello, Mr. Wang next door!"

Beside Qin Liang, Yang Duo'er smiled and was about to introduce herself to Brother Liang. Unexpectedly, after Brother Liang finished speaking, something seemed off about his face, and then... as if he had forgotten about her, he finished exchanging pleasantries and went up to the conference room.

"Back then, all we received were missiles, not control devices. So, we had to develop the infrared optical aiming device, angle measuring instrument, and control system ourselves," Wang Xing said. "Upgrading from manual control to semi-active control required a series of complex circuits, and we experimented for years without success..."

The missiles we acquired back then were salvaged from the battlefield; they were unexploded ordnance. While we could indeed obtain some technology by using them for reverse engineering, there were also many technologies that we were destined to miss, such as the missile control system.

"Actually, the control system of our anti-tank missile is very simple. A straight line connects the launcher and the target, and the missile moves along this line. If it deviates from the line, it corrects itself. Previously, it was manually controlled, but now it is automatically controlled. We have designed a special integrating circuit..."

"Why not use a computer to control it?"

This question left everyone dumbfounded. Most of the engineers present were middle-aged, and the few young people were not graduates of Northwestern Polytechnical University. They knew very little about such high-tech things as computers!

"Let our Computer Science Department at Northwestern Polytechnical University help us out. For such a simple control system, an 8086 chip is enough. Also, the data transmitted through these wires needs to be converted from analog signals to digital signals, making it less susceptible to interference..."

In this era, most engineers only know how to work with analog circuits. To achieve a certain function, they need to use transistors and other components to form various circuits. This requires ingenious techniques. Even an error in the resistance value of one resistor can cause the circuit to fail.

Digital circuits are simpler. Once the data sampling is completed, the rest is left to the computer. If the accuracy is not high enough, the program can be improved. Upgrades can be made using software. Programs like those for tackling top-down problems can all be implemented in software.

Historically, the HJ-8 missile has been continuously improved since its inception. The later E version was equipped with digital circuits, and missile commands were also changed to digital transmission, greatly improving its anti-jamming capabilities and bringing about a complete transformation in its performance.

Now that we've encountered this situation, let's hand it over to Northwestern Polytechnical University. There's no need to bother with analog circuits; let's go straight to digital circuits!

"Comrade Qin Liang, won't using computer control lead to an increase in prices?"

The cost requirements from higher authorities are also very strict!

"Of course not. The control system is all on the user end, it's not disposable. The missile has very few circuits, and it's not much different from the original design," Qin Liang said. "However, this only solves the problem of whether or not we have it. In the future, we will definitely need to develop more advanced guidance systems. After all, the future battlefield will be all about high technology."

The most important task now is to develop this missile to be mature enough to adapt to various platforms. Once this model is successfully developed, we can then develop a more advanced variant.

"What advanced guidance system?" Everyone present was very excited.

Northwestern Polytechnical University's technology has always been at the forefront of the industry, and the advanced nature of their proposed solutions is beyond doubt.

"Well... there are many technical approaches, it depends on how our colleagues at Institute 203 choose," Qin Liang said. "There are millimeter-wave radar guidance, laser beam guidance, laser semi-active guidance, and infrared imaging guidance, etc., each with its own advantages and disadvantages."

When the Apache evolved into the AH-64D, a large pumpkin was added to the top of the rotor, inside which was the famous AN/APG-78 "Longbow" fire control radar. The early version had a detection range of only eight kilometers, but that was enough for a helicopter. Later versions increased it to sixteen kilometers.

Millimeter-wave radar is small in size, consumes little power, and has high accuracy. Its disadvantage is that it has a short detection range. However, for helicopters, which are designed to strike targets within a few kilometers, this disadvantage is negligible. The use of millimeter-wave radar allows it to launch attacks even in adverse weather conditions, which is something that other optical targeting systems cannot match.

It's a perfect match for the Hellfire missile, which uses a millimeter-wave radar seeker!
However, since the radar needs to be installed on top of the rotor, the rotor structure will be more complex, and it is unknown whether our engineers can come up with an engineering solution to pass through the rotor blade clamps.

Laser guidance is divided into two types: laser beam riding guidance and laser beam riding guidance. The laser beam is emitted by the carrier aircraft and the missile flies along the laser beam, as if it is riding on the laser beam. This technology can only be guided by the carrier aircraft itself, so you can forget about A-to-B guidance.

Another type is laser semi-active guidance, which is similar to semi-active radar guidance. The laser beam is fired, reflected back, and enters the missile's laser receiver, adjusting its trajectory to accurately fly towards the target. This laser beam can be from other aircraft or a laser illumination device held by ground personnel. At the same time, the laser beam needs to be encoded because on the battlefield, a large number of missiles will definitely be launched at the same time.

As for infrared imaging, it's simple. Air-to-air missiles are currently being improved in this way, but its drawbacks are also obvious: it's definitely the most expensive, mainly due to the guidance system!
Each type of missile has its own advantages and disadvantages; it's all about choosing the right one.

However, compared to current wire-guided missiles, a significant advantage is that none of these types require the release of cables, allowing the missile's engine to directly eject flames backward!

Current missiles can only have openings on the sides to eject exhaust gases from the side. This is to avoid burning the tail cables, which would waste a lot of the engine's energy. At the same time, the missile's speed cannot be too high, otherwise the wire-guided system will not be able to keep up with the speed and will be torn off. Therefore, wire-guided missiles have speeds of over 200 kilometers per hour. After switching to other guidance methods, the speed will be greatly increased, and may even double.

“These technological approaches… are all quite good!” Wang Xing exclaimed. “There really is no way to choose.”

The meaning is quite clear: only children make choices; everyone wants it!

Qin Liang smiled and said, "Let's focus on perfecting our existing missiles first. As for other guidance methods, we can conduct preliminary research first and then choose the appropriate technology later."

"it is good."

There's no point in aiming too high; let's be down-to-earth first!
The helicopter project is now on its last leg. The next phase of research and development will be handled by a dedicated team. Qin Liang is exhausted after all this, but... there's still a lot to do!
Factory 430, conference room.

“Modifying an aircraft is not so easy.” Schroeder sat in his chair, looking at the Eastern experts present: “In everyone’s eyes, it seems like it’s just adding a power turbine to the back. In reality, there is a lot of work to be done. The fan part needs to be modified, the turbine itself needs to be changed, and the design of the power turbine is also a science. Even because the speed is different, the bearing stress is different, so it has to be changed. Of course, the biggest problem is the lifespan.”

For aircraft engines, a lifespan of a few hundred hours is acceptable. However, gas turbines on warships often need to sail at sea for months at a time! A lifespan of tens of thousands of hours is meaningful; otherwise, after a voyage, the stern steel plate would have to be cut and the engines replaced upon return!
"Such complex technology is not available in the East. The best solution is to import it from our Rolls-Royce."

Schroeder spoke with great arrogance, leaving everyone present perplexed.

The Navy issued a research and development task to improve the Spey engine into a modern gas turbine! The engineers were very excited. With the launch of the Spey ship modification project, the Spey engine truly blossomed in the East, and its future was bright.

But how do we change it?
Factory 430's research capabilities are still the weakest. The success of the Spey project back then was thanks to Northwestern Polytechnical University. As for this ship modification project now... Comrade Qin Liang isn't here!

They had no choice but to try to figure it out themselves. Given their limited resources, calling over the British consultants at the factory to discuss the matter together was probably the best approach. What if they could get some useful information out of them?

Now, the other party has reverted to its arrogant attitude. No way, we have to buy the technology patents from the UK!
Rolls-Royce is always looking to make money, as long as there's an opportunity!
The leaders present all wore serious expressions. It seemed they wouldn't get any useful information from the British, and they had absolutely no technological reserves...

Li Guofu, the factory director in charge of technology, said: "Mr. Schroeder, the conversion of the aero engine into a gas turbine is a task assigned to our Factory 430 by our superiors. No matter how great the difficulties we encounter, I believe that Factory 430 can overcome them. As for technology import... we are currently exporting a lot of our technology to Rolls-Royce. We can no longer import it from you."

Schroeder smiled and said, "In that case, forget it. Gentlemen, on behalf of Rolls-Royce, you are always welcome to request technical guidance."

This guy has got all the Asians figured out!
After Schroeder finished speaking, he stood up and was about to leave when the door opened.

"Everyone, I'm here!"

Qin Liang!

Everyone got excited when they saw Qin Liang come in.

"Comrade Qin Liang, you've finally made it!"

"Yes, we've been waiting for you to upgrade the Spey!"

Qin Liang nodded: "Yes, I came over as soon as I finished other things. Everyone, the technology of converting the Spey into a marine gas turbine is not difficult... Oh, our Rolls-Royce friends are here too!"

Schroeder smiled and said, "Yes, we will also participate. Please rest assured that we will definitely provide technical guidance."

Schroeder decided not to leave; he wanted to stay and see what they would say.

"Well, this modification is divided into several parts. I'm here to assign tasks." Qin Liang looked at everyone: "First, the front fan needs to be removed and replaced with a compressor. Taking this opportunity, we'll increase the pressure ratio. Even if we can't increase it to 25, we should at least increase it to 23."

To provide greater thrust, turbofan engines are designed with two bypass ducts, an inner and an outer one. The larger the outer bypass duct, the greater the thrust.

However, for a gas turbine, this bypass duct is meaningless and will instead become a drag. After all, the fan will also waste power, and the power of the fan will not be transmitted to the power turbine.

The Spey uses a five-stage fan and a 12-stage high-pressure compressor. All these components combined result in a mere 20 pressure ratio. Now that it's being upgraded to a gas turbine, the fan needs to be changed, so this is a good opportunity to increase the pressure ratio.

The higher the pressure ratio, the higher the engine efficiency. Third-generation engines, such as the F100 engine, have a pressure ratio of around 25.

Our team has upgraded to 23, which is not a huge leap forward. After all, we have all the technical data on Spey. We also improved the fan and turbine back then. Now, we can decide how to improve it ourselves!
Schroeder's eyes widened. A pressure ratio of 23! With this improvement... Spey's performance could be boosted significantly!

Switching to marine gas turbines will also improve thermal efficiency, and this data is very important.

"The low-pressure turbine also needs to be improved, while the high-pressure compressor will retain its original structure. We will use a computer with a scale of 10 billion operations per second to conduct simulations, which will make the research and development more efficient."

Schroeder's eyes widened even more.

Products like aircraft engines, which involve complex fluid dynamics, often cannot be simulated by computers. They can only be tested, and improved time and time again. However, this is also due to the insufficient computing power of computers.

If we had a computer capable of performing calculations up to 10 billion times, we could use it to do the calculations and get them pretty close to the mark. Once it's on the test bench, we could just make a few minor modifications.

Anyway, gas turbines are different from fighter jet engines. They don't frequently change the throttle to cause sudden changes in speed. As long as the high and low pressures are matched, they can operate stably!

Even Rolls-Royce doesn't have the facilities for this kind of research! I... really want to join in the fun!

"Next is the gas generator. Considering the characteristics of warships, I think we should start by studying it based on diesel fuel," Qin Liang explained.

Aircraft engines can only use aviation kerosene, but after being improved into gas turbines, they can use a variety of fuels. In fact, any combustible fuel can be used. In the early days, some designers even designed them to burn heavy oil, the cheapest fuel commonly used in boilers.

Although it could burn fuel, after running for a while, too many impurities accumulated on the turbine, so it was eventually abandoned.

Many warships are powered by a combination of diesel and gas turbines, using diesel engines at low speeds and gas turbines at high speeds. Therefore, it is best to use diesel fuel for the gas turbines, which allows for a unified fuel supply.

　PS: Our Z-19 attack helicopter also has a big pumpkin on its top, which houses the millimeter-wave radar.

　　
　
(End of this chapter)