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

Chapter 279 The Comanche Helicopter That Came Out of a Science Fiction Novel

Now, Qin Liang showed these Americans the three-view drawing of the Comanche helicopter that would later become famous, and their eyes were filled with shock.

They knew that the era of stealth aircraft had arrived in the field of fighter jets, but they never expected that even helicopters could have stealth versions!

This...this is unbelievable!

"Does this stealth refer to radar stealth?" Ray Leo swallowed hard before asking.

As an excellent helicopter designer, he can fulfill any requirement put forward by the military and satisfy users, but... those are all for conventional helicopters. If it is a special helicopter, they can't do it.

For example, the US military has a CH-47 Chinook helicopter in its inventory. Unlike single-rotor helicopters, it has a long and slender fuselage with a rotor mounted at the front and a rotor at the rear, arranged in a staggered pattern with the front lower than the rear. However, this aircraft is a Boeing product.

In fact, this wasn't Boeing's original business. Boeing acquired Futtor Corporation, which had been researching tandem rotor aircraft for decades, leading to the creation of the CH-47.

The Russian Karimov Design Bureau, on the other hand, used a coaxial rotor system with two rotors on top of the helicopter, one above the other. This eliminated reaction force and the need for a tail rotor, reducing the helicopter's length while significantly increasing its height. Sikorsky couldn't build this either; they lacked the technological reserves.

Currently, Sikorsky's only advantage is its conventional layout; as for stealth technology, their technological reserves are naturally zero.

"Well, it's different from fighter jets. If we want this kind of aircraft to truly adapt to the battlefield environment, we need to achieve stealth capabilities in four aspects: radar stealth, infrared stealth, visual stealth, and noise stealth."

Fighter jets only need radar stealth, because generally, radar is used to detect fighter jets at long distances, and infrared stealth is only needed when they get close. This only requires dealing with the tail nozzle.

Because fighter jets are so fast, visual and noise levels are irrelevant.

But helicopters are different. They fly at treetop height. Even if they can't be seen on radar, how about on an infrared imager? They can even hear the sound from afar, look up, and know that a helicopter is coming. They can then pick up a Stinger anti-aircraft missile, or even just an RPG rocket launcher.

Now that this concept has been put into words, it has caught the attention of everyone present. Yes, that's exactly how it should be done!

The fact that they can come up with clear concepts shows that Easterners have studied this field very seriously!
"So how exactly is this achieved?"

Qin Liang looked at everyone present and then said, "Christian, why don't you analyze this for everyone?"

Explaining directly is pointless; let's test them instead.

Christian stood up: "Yes, teacher! First, let's look at the shape. This aircraft has obvious polyhedral features. The purpose of this design is to reflect radar waves in other directions, thereby reducing the beam reflected back to ground radar..."

Thanks to Qin Liang's efforts, stealth technology is no longer a high-tech thing; many people know about it and can talk about it at length!

"As for infrared stealth, it should involve processing the engine. Judging from this design drawing, the engine is covered by an outer shell. If I'm not mistaken, a cold air mixing system is definitely used inside to greatly reduce the temperature of the exhaust gas."

In fact, many helicopters are now using this technology. Take the Mi-24 that Pakistan sent, for example. It has a device added to the tail of the engine that mixes the outside air with the engine exhaust. When it is expelled, the temperature is reduced significantly.

However, one drawback of this approach is that the power output is reduced to some extent due to the restricted exhaust. This is similar to the later upgrades to car emission standards, where the result was a replacement of the exhaust pipe, incorporating more and more high-tech features, but also making the engine exhaust increasingly obstructed.

"As for visual camouflage and noise camouflage, well... I'm not sure."

"Hmm, not bad, Christian, it's already very good that you thought of this much." Qin Liang offered some encouragement: "Now, let me add a few more points. First, let's talk about radar stealth. In addition to optimizing the external design, we also use a lot of composite materials on the fuselage surface to further reduce the radar cross-section. After optimization, our fuselage radar cross-section will be reduced to less than 0.01 square meters."

What does this mean? It means the size of a car has been reduced to the size of a ping-pong ball!

Whether we can do it or not, we'll talk about that later. Anyway, we're going to make this boast. If the F-117 can do it, of course we can too!
The group of Americans listened with their eyes wide open.

"Regarding infrared stealth, it's similar to what Christian said. We added a specially shaped protective cover to the outside of the engine. In addition to reducing the radar cross-section, it can also house a cold air mixing system. The engine air intake adopts a diamond-shaped design to reduce the radar cross-section, and the exhaust temperature is almost the same as normal temperature, thus avoiding attacks from the most common infrared-guided air-to-air missiles."

This was something everyone could understand, and they nodded frequently.

"Next, let's talk about visual stealth. On the fuselage, we will use a unique dark gray non-reflective coating, which is similar to the background color, making it virtually invisible, especially at night. As for daytime, it will also be impossible to see from a distance. The cockpit glass will use a flat panel design to reduce sunlight diffuse reflection, and there's also this propeller..."

When Comanche first appeared, Qin Liang was very impressed, exclaiming that it was incredibly high-tech!

Therefore, he was very curious about these designs and knew the technologies used by heart.

"Look at this propeller blade. Although the engine's power isn't very high, we designed it with five blades. Do you guys know what the advantages are?"

The number of rotor blades is closely related to the engine's power. Light helicopters only need two blades, which makes the rotor design simple. Slightly heavier helicopters have three blades, while medium-sized helicopters generally start with four blades, such as the common Black Hawk helicopter.

As for larger ones, such as the American CH-53, the early version had six blades, which were later upgraded to seven blades, while the world's largest helicopter, the Mi-26, had eight blades from the start.

For the helicopter in front of us, four pieces would have been enough, but we designed it to have five!
"Is this to reduce the rotor speed?" Ray Leo said.

As a top helicopter designer, I certainly know the ins and outs of this.

"That's right, it's about reducing the rotation speed. Our research has found that when the rotor speed is reduced, the flicker frequency reaches 36 Hz, which is beyond the range of human vision."

This falls under the category of human science. The human eye can't see everything. 36 Hz is a very important data point. Now, by using this method, the propeller can be made to disappear from the human eye, and the largest visual image of the helicopter can be eliminated.

"At the same time, the rotor noise will be greatly reduced after the speed is reduced." Qin Liang continued, "By carefully designing the shape of the rotor tip, we can make the noise it produces almost the same as the background sound. The tail rotor has also been changed to a ducted type, not only to reduce the possibility of being hit, but also to reduce noise. Our ultimate goal is to make the overall noise of the helicopter almost the same as the sound of normal conversation."

In a single-rotor helicopter, as the large rotor at the top rotates, the fuselage will also rotate in the opposite direction due to the reaction force. This requires balance, which is achieved by installing a tail rotor at the rear to blow air to the side and balance the reaction force.

So, in movies, if a helicopter gets hit in the tail rotor, it will spin and fall.

The tail rotor can be exposed or enclosed, as is the case with the French-made Dolphin helicopter. American-made ones generally have ordinary tail rotors. The design of this helicopter uses a duct to enclose the tail rotor, the most important purpose of which is to reduce noise.

It's absolutely unimaginable that a helicopter could fly with a noise level similar to a human's voice, but looking at these designs now, they're quite clever, clearly an effort to reduce the probability of being detected.

"And what about the engine noise?" an engineer asked.

An engine that can easily reach tens of thousands of revolutions per minute is a huge source of noise. As you can see from watching movies, the noise level increases rapidly when a helicopter takes off!
"Everyone, I just introduced the air intake. Do you see where the engine's air outlet is?"

All we could see was a bulge on the outside of the engine, which we knew was for mixing with outside air. But what about the air outlet?

"Where is the vent?" Ray Leo asked.

"The slotted exhaust ports on the tail boom not only significantly reduce the infrared signature but also have a noise reduction function. In addition, the engine casing is covered with special sound insulation material."

This is just like the exhaust pipe of a car engine! It comes out of the engine and extends all the way to the rear beam! Even the highest decibel noise will be gradually absorbed here!

This helicopter has many revolutionary designs!

"I never imagined that the East would possess such advanced helicopter design technology!" Ray Leo exclaimed. "Our inspection trip has been very fruitful. Would you sell these technologies?"

“Teacher, our Sikorsky company needs these technologies!” Christian said.

"Well, since you need it, of course we can sell it, but... the price will be very high." "Price is not a problem, teacher. Just name your price, and we can definitely accept it!"

With these technologies, Sikorsky will not have to worry about being eliminated by Boeing's tiltrotor aircraft. It can continue to develop and even grow stronger in the future, becoming the strongest helicopter company in the United States. If these technologies fall into the hands of other companies, it would be a disaster for Sikorsky.

So, I have to buy it!

"These technologies are all in the early stages of development. If they are successfully developed, we believe they are worth at least one billion. Right now, since many of these technologies are still conceptual, and you are our friends, we'll ask for thirty million US dollars!"

The price Qin Liang quoted amused the Americans. "That's it? What's this little bit of money?" they thought. They were actually prepared to offer a much higher price.

“Okay,” Ray Leo said. “We can give you the money, but… we hope to exchange it for products. Our S-70 helicopters cost six million dollars each, so this thirty million dollars is exactly the price of five S-70 helicopters…”

With the technology acquired and the product sold, this was undoubtedly the best option for them.

Hearing his words, Yang Duo'er, who had been silent until now, spoke up: "Mr. Ray Leo, isn't it a bit... unfriendly to your friends to do business this way? We only offered this price because of our friendship. If it were another company, such as Bell, we would have asked for at least fifty million US dollars!"

Ray Leo said somewhat awkwardly, "The two S-70s that you have already ordered don't need to be paid for by you. Consider them a gift from us!"

Exchanging seven S-70s for this data that Qin Liang spent about a week compiling is naturally... a very good deal.

"Okay, deal!"

"Father, can I stay in the East and work on this project with our Eastern friends?" Christian asked.

As Qin Liang just said, these technologies are still in their infancy, and many are conceptual. We exchanged helicopters for these technologies, but we still need to refine them to a practical level. Therefore, we need to continue our cooperation. Christian stayed here because he wanted to learn more about these technologies!
Moreover, his involvement in this project will allow him to accumulate experience for the future. Once he starts working, he will be able to research the most advanced helicopters, and with his father's connections, he will soon become the chief designer!

Ray Leo looked at Qin Liang: "Qin, what do you think? If possible, we hope to send ten engineers here to work with you on the specific technology of this stealth helicopter."

"Well, well..." Qin Liang looked slightly embarrassed.

"How about adding two more S-70 helicopters as part of our R&D investment?"

"Just two S-70s..."

"Then three will do. That way, you'll have a total of ten S-70s, giving you a decent fleet of medium-sized helicopters. What do you think?"

"It would be even better if some spare parts were included."

"Okay, I'll deliver the spare parts to you as usual!"

"Okay, on behalf of Northwestern Polytechnical University, I welcome you to join us! However, the work location will be in Chengdu, where we have a university-run factory that specializes in developing helicopters."

Christian, that guy, once pursued my wife, so I can't let him stay at Northwestern Polytechnical University. I have to send him away. Besides, there's no helicopter technology here, so it's easy to be exposed. Go to Factory 5701, which originally repaired helicopters. Now, we can upgrade it to map and copy helicopters. That will definitely satisfy these Americans. I'm not trying to fool them!
Moreover, and more importantly, the news of the Mi-24s that defected from Afghanistan could not be kept from the Americans. They had already infiltrated Afghanistan to the point of being completely infiltrated. Now, by openly showing them off, they could win the favor of the Americans.

"Chengdu? I've never heard of your school-run factory." Sure enough, Ray Leo was a little curious.

"Well, it was only recently established."

recent!
Ray Leo realized: "Could it be for researching the Mi-24?"

"Ahem, this is it..."

"Can we go take a look?"

Pakistan acted too quickly. The Americans had barely received the news when the helicopter was sent away. They were furious, but there was nothing they could do, since they still had to rely on Pakistan.

Now, coming to the East to see the Russian Mi-24 up close is also very important.

"Please wait a moment, everyone. I need to report to the relevant departments."

In the 1980s, making calls within the province was relatively easy, but long-distance calls across provinces were very complicated. However, having special privileges made things different. For the sake of convenient communication, the higher authorities specially coordinated a dedicated line for Northwestern Polytechnical University, allowing students to make long-distance calls freely within the country.

Soon, the call reached the capital.

"Qin Liang, congratulations on your fortune!"

Hearing the voice inside, Qin Liang was stunned: "Old Lin, what kind of fortune are you trying to make? We're so poor we're practically begging! What's with all this helicopter stuff? The higher-ups haven't allocated a single penny, it's giving me a real headache..."

"What's there to worry about? Do you think I can hide this from you? The people from Sikorsky are already there. Tell them honestly, how much did you swindle them this time?"

"Not many, only ten S-70s."

"Ten helicopters! My goodness! That's enough to equip an entire helicopter battalion for our air force! All ten of these are for our air force. How much was it again? Six million per helicopter, right? Our air force will cover that cost!"

"RMB or USD?"

"Of course it's RMB, 60 million RMB! That should be enough for helicopter development, right? In the end, the money still comes from our air force..."

This is standard practice: when selling goods, domestic payments are in RMB, while international payments are in USD, and the price remains the same. The Air Force does the same thing when buying goods, which is somewhat like taking advantage of a crisis.

"Old Lin, no, this is too cheap!"

"In the future, if you at Northwestern Polytechnical University need to use a helicopter for business, just give us a heads-up and we'll make the arrangements!"

Qin Liang really wanted to say, "Old Lin, your air force helicopters will be transferred to the army in a few years! Your current promises are useless!" However, it was inconvenient to say such things that were beyond his control.

"Factory 5701 was given to you directly by the Air Force. Did the Air Force say anything?" Hearing Qin Liang's hesitation, Old Lin immediately changed his attitude.

This is a classic case of playing the bad cop first and then the good cop; in short, Northwestern Polytechnical University has no choice but to agree.

"Old Lin, let's get down to business. The Americans want to keep some of their people here to participate in that project I was bluffing about. I plan to put them at Factory 5701..."

"Okay, as long as you agree to the previous price, the Air Force has no objection to your terms!"

After hanging up the phone, Old Lin was overjoyed.

"Old Zhang, Old Zhang, you've struck it rich! You've struck it rich!"

　PS: Comanche helicopter.

　　
　
(End of this chapter)