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

Chapter 459: The engine alone requires two billion in R&D funding?
On June 18, Qin Liang returned to Northwestern Polytechnical University, accompanied by... Ben Richie and others.

That's right, the Lockheed people followed him to the capital. After all, the Dawn Goddess project was Lockheed's only chance to turn things around, and they had to seize it!

Qin Liang stayed in the capital for three days, making some moves among various departments, and then... he ran into Ben Richie and his group, so he had no choice but to take them with him back to Northwestern Polytechnical University.

However... Northwestern Polytechnical University has never let Qin Liang down!
In the conference room.

"For hypersonic aircraft, ramjet engines are an inevitable choice." A young college student, with only a wispy, unshaven mustache, spoke with unparalleled professionalism.

"Ramjet engines are divided into two types: subsonic and scramjet. To achieve speeds of Mach 5 or higher, a combination of subsonic and scramjet engines is the only way. Our Department of Aero-engine Engineering at Northwestern Polytechnical University already has a complete design scheme..."

At this point, the college student glanced at Qin Liang.

"Senior Brother Qin Liang, the following presentation is confidential. Can we tell these American friends about it?"

Qin Liang nodded: "Of course, go ahead and say it!"

Ben-Ritchie and the others were very satisfied. "Excellent, excellent! We are the first Western company to cooperate with Northwestern Polytechnical University after the opening of the East's doors. Northwestern Polytechnical University's research secrets can be completely disclosed to us. This is a heavy trust!"
"We have combined subsonic and scramjet engines to form a unique combined subsonic and scramjet engine. Its biggest feature is that it is used in afterburner combustion..."

The Americans opened their eyes wide.

On the way here, they were discussing what technological approach the Easterners would use. Unexpectedly, it turned out to be a combination of sub- and super-fuels, with sub-fuels supplementing super-fuels. This solution is brilliant!

“Excellent, excellent! From a technical standpoint, it’s entirely feasible!” Lockheed engineer Shadler, who was accompanying them, had a bright look in his eyes. “However, ramjet engines cannot start from zero. How do you plan to solve this problem?”

"Of course, a turbofan engine is installed at the front."

"Turbofan?"

"That's right. This saves fuel during takeoff. Once at high altitude, as long as the bypass duct is shut off, it becomes a turbojet engine. At the same time, the afterburner can be opened for acceleration. Once the speed reaches Mach 2.5, the subsonic ramjet engine can be used. Above Mach 3.5, dual-mode can be used..."

This engine needs to cycle through four modes!

This is incredibly technically challenging!
It's important to understand that the J-58 engine used in the Blackbird was simply switching between turbojet and ramjet engines. Moreover, the ramjet engine wasn't purely ramjet; the four-stage compressor at the front of the engine continued to operate, but its pipes were connected directly to the afterburner to create a similar effect to a ramjet engine.

The YF-23's variable cycle engine uses bleed valves to switch between turbofan and turbojet engines.

Now, turbofan, turbojet, subsonic ramjet, and supersonic ramjet are combined together?
This difficulty level is absolutely insane!
"How are these engines put together?" Sadler asked.

"It depends on the aircraft design and the volume allocated to the engine nacelle. If it's relatively long, then it's connected in series; if it's relatively wide, then it's connected in parallel."

What?
Are there two other options?
"Could you tell me everything?"

“Sure, that’s easy.” The college student continued, “The so-called parallel connection means that they are placed side by side, either vertically or horizontally. In short, they have to be thick enough. Taking vertically as an example, the upper channel can be used to place a turbofan engine, and the lower channel can be used to place a ramjet engine. The upper channel can be curved, and it is best if the lower channel is straight. The advantage of this is that the nozzle distance is short and the thrust loss is small.”

He spoke while displaying PowerPoint slides, accompanied by pictures, making the presentation clear and intuitive.

"As for the tandem configuration, it involves a central turbofan engine, a mode switching valve in front, and a ramjet engine in the rear. The advantage of this is that they can share an air intake, saving space..."

Sadler looked at it carefully, and after a while, he exclaimed, "You Easterners are really clever. How did you come up with such imaginative ideas?"

The smartest people in the world are us Easterners!

The United States has advanced technology, but it doesn't produce scientists domestically. It relies on absorbing the world's brightest minds to come to the US!
Where do the brightest minds come from?
East!

In the United States, a large number of those who have made outstanding contributions to science and technology are Chinese!
Therefore, once they started to reject us, their technology began to fall behind rapidly.

Now, these brilliant minds have remained in the East, especially at Northwestern Polytechnical University!

In recent years, Northwestern Polytechnical University has seen its admission scores rise continuously due to the large number of applicants, even surpassing those of Tsinghua and Peking Universities!

Those who could get into university in the 1980s were all the pride of heaven, not to mention the top talents among the pride of heaven!
These outstanding talents, after arriving at Northwestern Polytechnical University, continue to influence each other. They complete four years of courses in two years and spend the remaining two years working on projects. This is almost the basic understanding of every student who enters Northwestern Polytechnical University!
"You said it yourself, it's because we're smart!"

Westerners rarely praise someone for being smart; they value effort more. For example, they might praise someone for being hardworking or diligent, as these are the results of their own efforts. Beauty and intelligence, on the other hand, are innate, something you're born with.

At this point, if the other party praises the students from Northwestern Polytechnical University for being smart, it means they truly admire them.

“Qin, according to the design drawings you gave me before, the engines can be placed horizontally in parallel, which is perfectly feasible!” Ben-Ritchie thought of the design drawings Qin Liang had drawn at Lockheed Corporation.

In reality, Qin Liang drew it based on his memories from later generations. To put it simply, it was all CG images from the internet. To make it look better and to make the plane look more futuristic, he designed the engine compartment to be very spacious. Especially towards the end, it was almost three meters wide.

Therefore, it is perfectly fine to place the ramjet and turbofan combined engine side by side in the engine compartment!

Qin Liang smiled and said, "Let's discuss the specific data again. The total weight of this reconnaissance aircraft should be over eighty tons, so the thrust during takeoff should be at least thirty-five tons. In that case, the thrust of a single turbofan engine should be at least eighteen tons. To reduce fuel consumption, it would be best to achieve this thrust without afterburner."

Eighteen tons!
The Americans don't have any!
Even the B-2 bomber used by the United States has an F118 engine, which only has a thrust of 7.8 tons per engine!
The F101 engine used in the B-1B has a maximum thrust of only 14 tons, and that is with afterburner thrust!

To achieve a maximum military thrust of eighteen tons...

how can that be!

"Qin, the afterburner reaches eighteen tons, it seems... there shouldn't be any problems, right?" Ben Richie asked.

This is a reconnaissance aircraft, not a fighter jet. We don't need to pursue a thrust-to-weight ratio of more than 1, and we might not even need to achieve a thrust-to-weight ratio of 0.5. At worst, we can just take a longer run.

"An afterburner thrust of 18 tons is not impossible, but... if the afterburner thrust is only 18 tons, can such thrust allow the aircraft to reach a speed of Mach 2.5, meeting the conditions for starting the ramjet engine?"

The Americans stopped talking.

Their Blackbird didn't have to face this problem because it was a combination of turbojet and ramjet engines. At high altitudes, as speed increased, the airflow from the compressor could be directly directed to the combustion chamber at the rear, allowing it to be used as a ramjet engine.

In fact, this is not a ramjet engine in the full sense.

A real ramjet engine has no unnecessary parts; it's just a simple tube! And this kind of engine can't start unless the speed is sufficient!

The requirement of Mach 2.5 is actually quite low. If the design is not good, it may not even start until Mach 3!

Can an engine with an afterburner thrust of 18 tons propel the Aurora, weighing over 80 tons, to a speed of Mach 2.5?
Enough!

Because as speed and altitude increase, the engine thrust decreases continuously!
Take the RD33 for example. Its ground test thrust was 8.3 tons, but at an altitude of 10,000 meters, the thrust dropped to 6.4 tons. This is even with the turbine blades allowed to heat up to 150 degrees Celsius at high altitude. If you were to use a lousy product like the Spey, the thrust would drop to only one or two tons at high altitude!

With a maximum military thrust of 18 tons, afterburner would require at least 25 tons or even more for ground testing. This way, even if the thrust is reduced by more than half at high altitudes, it would still leave 10 tons.

Two units would weigh twenty tons.

Using these two engines, we should be able to propel an 80-ton aircraft to Mach 2.5!
If we could switch between turbofan and turbojet engines, the reduced frontal area at high altitudes would make it easier to achieve the Mach 2.5 target!

Therefore, this condition is necessary!
"But we don't have a military-grade engine with an 18-ton thrust!"

“It’s alright if you don’t have it, we have it on hand. We just need to modify the RB211 a bit to meet your needs,” Qin Liang said. “Of course, you can also make your own choice. We can reserve the bypass duct of that turbofan engine for you to match. Next, we’ll talk about what to do after Mach 2.5. Come on, let’s continue.”

The college students smiled.

"Okay, let's continue. When we get to the ramjet engine stage, we don't need to worry about insufficient power anymore. Once we get past Mach 2.5, it's our world!" For ordinary aero engines, there are two main ways to increase thrust: increasing the pressure ratio of the compressor at the front. The higher the pressure ratio, the more air is compressed, and the more combustion is supported; and increasing the turbine inlet temperature at the rear. The higher this value, the more heat-resistant the engine is.

And what about ramjet engines?
These are not even considered; the best one is the one that's directly chosen!
The most incredible engine in the F-22, the F-119, has a total pressure ratio of only 35, which is already the pinnacle of turbofan engines.

And what about ramjet engines?
You don't need anything else, as long as you're fast enough to force the air in, that's enough!
Specifically, if it operates under Mach 3 airflow, the pressure ratio is 37, which is higher than the F119 engine when it is working at full power!
As for turbochargers? Sorry, ramjet engines don't have turbochargers!
The F119's turbine inlet temperature is only 1950K, which is equivalent to 1677 degrees Celsius. But what about a ramjet engine? Without a turbine, it can easily reach over 2000 degrees Celsius!
"Simply put, according to our calculations, if the frontal area of ​​a ramjet engine is one square meter, then at an altitude of 10,000 meters and a speed of Mach 3.5, it can generate thirty tons of thrust..."

Is one square meter a large area?

Take the F119 as an example. Its fan diameter is 114.3 centimeters, which translates to a frontal area of ​​about one square meter. Its afterburner thrust is only 15.9 tons!

At high speeds, the thrust generated by the simple ramjet engine is incredibly powerful, and its thrust-to-weight ratio far surpasses that of other engines, easily exceeding 15, or even 20 or more.

The university students gave a very detailed presentation, which fully demonstrates that Northwestern Polytechnical University has conducted in-depth research in this field!
“Good, very good. Hearing you say that gives us even more confidence in this engine,” Ben Richie said. “We hope to jointly develop this engine!”

"Mr. Ben Rich, you're an aircraft manufacturer, right? Shouldn't the aircraft engines be supplied by other companies?" Qin Liang asked curiously.

"Yes, there are definitely other companies that provide supporting components. For example, for the turbofan engines we need, we can choose from General Electric and Pratt & Whitney. However... as for ramjet engines, no company has a mature product for them. So, Lockheed will handle it ourselves!"

Generally speaking, companies that manufacture aircraft don't produce engines; specialized tasks are handled by specialists. However…

Lockheed is in a bad situation! With projects being snatched away one after another, if they don't secure more projects, their future will be bleak.

Moreover, ramjet engines are clearly the hope for the future. After this collaboration with Northwestern Polytechnical University, Lockheed Martin can enter this field and produce more hypersonic aircraft in the future!

So they decided to do it themselves!

"Alright, let's estimate the R&D costs first." Qin Liang looked at the person giving the presentation: "Come on, students, you should have estimated the R&D costs by now, right?"

"Ignoring the turbofan engine itself, and only considering its integration with the ramjet engine, it would probably require..."

How much do you want?
His gaze fell on Qin Liang, who was stretching out one hand and moving it back and forth.

Five, ten, fifteen, twenty...

Two billion US dollars!

How many?

The Americans were stunned.

Qin Liang was also stunned. He gestured, "It's five hundred million US dollars! I was afraid you couldn't see it clearly, so I flipped through it a few times. Did you add it up?"

Don't you even consider whether Lockheed can afford it?
It's worth noting that the F119 engine used in the F-22 fighter jet, including the initial research and development costs, cost only $23 billion in total.

Talented people emerge in every generation!

Back when I was an undergraduate, students at Northwestern Polytechnical University wouldn't dare to report such figures. In recent years, the younger students have seen a lot!

"This is the main power source for future aircraft! The research and development costs are not expensive at all, Senior Brother Qin Liang, don't you think?"

The college student we just introduced clearly realized something was wrong and quickly tried to salvage the situation.

Qin Liang smiled and said, "That's right, the R&D funding isn't expensive. However, considering our Lockheed friends' ability to accept it, how about this: we each invest half, conduct joint research, and share the technology? Ben Richie, my friend, what do you think?"

Even if it's cut in half, it's still a billion dollars. Keep in mind, this is just the engine, not the whole machine!

The project Lockheed is called Project Aurora. How much would the whole system cost?
Ben Rich took a deep breath: "I think we should ask Pratt & Whitney to take on this project."

They're giving up; they can't afford it!

In the United States, the two major engine giants are Pratt & Whitney and General Electric. In the development of fourth-generation fighter jets, Lockheed chose Pratt & Whitney's F-119, while Northrop chose General Electric's F-120. Later, Lockheed cancelled the project, and the F-119 project was never completed.

Therefore, entrusting the development of this engine to Pratt & Whitney is a way of taking care of our brother company.

He didn't know it was a trap.

"Yes, that works too. Come to think of it, this is our first time working with Pratt & Whitney."

We had a close collaboration with GE when manufacturing fan blades before, but as for Pratt & Whitney... we hadn't really had much contact with them before.

"Well, let's talk about the overall design."

"Okay, but... it's about time. How about we go to the cafeteria first?"

"it is good."

It's become a regular practice for these foreigners to dine in the cafeteria at Northwestern Polytechnical University. Not only can they enjoy Eastern cuisine, but they can also meet the university's students and perhaps even uncover some secrets.

Of course, in reality, they almost never succeeded. Students at Northwestern Polytechnical University are all educated and know exactly what to say and what not to say.

As everyone headed towards the cafeteria, Ben Richie looked out the window and said to Qin Liang, "Qin, don't worry about me, we'll go line up for food ourselves."

"it is good."

Qin Liang finally had time to be alone with his people. He looked at the student who had been busy all day and asked, "Junior, what's your name?"

"Liu Xiaoyong".

This name sounds familiar... wait...

This guy was the chief designer of the ramjet engine in the East in later generations!
Our YJ-12 can fly at supersonic speeds throughout, thanks to the engine designed by this guy. Our Changjian-100 uses a subsonic combustion engine, with a speed below Mach 5. The Changjian-1000 combines subsonic and supersonic speeds; the exact speed is unknown, but some say it can fly at Mach 10. It was also designed by this guy.

Qin Liang had no idea that this guy was actually a graduate of Northwestern Polytechnical University!

"Senior brother?"

"Yes, yes, Xiaoyong, do a good job. The ramjet engine technology of Northwestern Polytechnical University depends on you!"

"Don't worry, Senior Brother Qin Liang, class 7209 will have no problem handling this! But... do we really have to develop this technology together with the Americans?"

"Of course not! We'll develop aircraft engines together with them, and use their funds to develop missile engines ourselves. We'll take it slow and steady, from small to large, there's no rush."

"it is good."

"By the way, we need to keep this a secret. We can't let them learn our true skills."

"Of course, no problem. Only we have a hypersonic wind tunnel. If we don't let them in, all the data will still be up to us. We can make up whatever we want."

(End of this chapter)