Siheyuan: I eat melons while doing scientific research

Chapter 1421 The conditions are pretty good? (I'm too tired to continue, I'll save the 4k and 1k for tomorrow)

"What are the benefits of going to such lengths to develop this flying wing configuration? Is it worth all this effort?" We need to get to the bottom of this.

Speaking of this, the comrades from Chongfei were no longer sleepy, as they knew something about it.

They know the benefits of this thing, but they can't solve the drawbacks of this configuration, so for the time being they can only watch helplessly.

"This configuration has high lift and high internal space utilization, so under the same conditions, it has a large payload and long range," the colleague who went back to flight said with great familiarity.

This is the core reason why flying wings were initially valued; stealth was not even a primary concern. With its high payload and long range, the flying wing is actually one of the most thorough lifting body fuselage configurations.

When Hans was desperate during S2, he pinned his hopes on advanced weapons to turn the tide of the war, and came up with a lot of abstract ideas, the most abstract of which was that he actually wanted to build flying saucers.

However, upon closer examination, there are actually quite a few good ideas, such as the Ho-229 flying wing.

"Long range and heavy payload?" Upon hearing this, the comrades from the Air Force Equipment Bureau were no longer sleepy. Isn't this the innate holy body of a bomber?
"Yes, to put it this way, if we use this configuration, conservatively speaking, using an engine with thrust similar to the existing Tu-16 copy, it can achieve a range of 7000 kilometers while carrying 5 tons of ordnance."

This is actually why Gao Zhendong chose the B-21 instead of the B-2; the size is just right. Although it is still unclear what engine the B-21 uses, the most likely F-135 engine has an intermediate thrust of just over 12 tons.

Considering that the Tu-16's engine, although only 8.7 tons of thrust, is at the technological level of the 50s and is a turbojet engine, thrust can be increased by changing materials and adding turbofans, so the difference in non-afterburning thrust between the two will not be too large.

He didn't intend to build a B-21; that was impossible. He just wanted to build something that was close to the B-21.

At the same time, he didn't expect to perfect it in a short period of time. This thing doesn't need to be too perfect. To put it bluntly, as long as it can fly normally and its stealth performance is basically achieved, even if the payload is only 2 tons, the comrades in the army will be laughing their heads off. For example, by simply changing the materials, the thrust of the Tu-16 copy could be increased to nearly 10 tons. This idea is actually not impossible.

Gao Zhendong's reported data was a direct discount on the B-21. The performance of that aircraft has not been publicly disclosed, but it is generally accepted that it has a maximum payload of over 13 tons and a maximum range of 8000 to 9000 kilometers. As for whether the maximum range is achieved with the maximum payload, it is still unclear, so Gao Zhendong gave a very steep discount.

Although this discount was quite steep, it was an unexpected bonus for the comrades in the Air Force Equipment Bureau. The Tu-16 has a payload of 3 tons and a range of 6000 kilometers, and there is still a significant difference between the two.

With this capability, even if it carries less, say 3 tons, it could barely reach the second island chain's fulcrum in the Western Pacific—Guan Island. After all, when things get really urgent, a bomber's combat radius doesn't need to be divided by 3 like a fighter jet; dividing it by 2.5 would be just about enough.

Being able to reach this place with a ballistic missile and being able to reach this place with a bomber are two different things.

After all, we don't have "dual nuclear and conventional capabilities" right now. Dropping a ballistic missile with this range is just painful! And considering the power of conventional warheads, the missiles aren't even accurate.

There's no such concern when it comes to dropping bombs.

Three tons of bombs, which is six 500kg bombs, can severely damage or even kill any warship except for aircraft carriers and S2 battleships. If we add some larger bombs weighing over one ton... wouldn't that be wonderful?

Furthermore, a strike range exceeding 3000 kilometers is a very important threshold. At the same time, Comrade Zhendong also stated that this is a "conservative" estimate; what if things turn out more optimistically with technological advancements? Wouldn't that...?

Their interest grew even stronger, and they asked the question the comrade from Chongqing Aircraft Industry Group hadn't finished asking: "So, what is the price?"

Gao Zhendong almost laughed out loud. This sounded familiar. Before he transmigrated, he had heard it online ten or eight times a day.

"Slow speed, difficult to operate, poor maneuverability," said a colleague from the Chongqing Aircraft Factory.

Actually, more than that.

The chief engineer of the Air Force Equipment Bureau and the Commissioner thought about it...

"The F-104 is difficult to operate, but Comrade Zhendong solved part of it just now, right? It's not a big problem if it's difficult at all. The key is that it can be operated." These days, there aren't so many fuss about it. The key is that it can be used. The F-104 is also difficult to operate, but the Western Hans, who was on the front line of the Cold War, used it very well. The key is that this thing has enough high-speed interception capability. When it comes to the combat power that is urgently needed, difficulties have to take a back seat.

"Poor maneuverability, this is just a bomber, what's the point of maneuverability? It's fine, it's fine."

"Slow speed...that's a problem..."

"It doesn't seem like a big problem, if stealth can really be achieved," said a colleague from the Air Force Equipment Bureau. "Besides, as long as the cruising speed isn't too low, it's actually acceptable. After all, bombers spend most of their time cruising, and the current mainstream bombers aren't actually that fast..."

At this point, Gao Zhendong reassured everyone: "The cruising speed is not low; it can reach Mach 0.7 to 0.8."

This is also the result of a discount.

"0.7~0.8? That's fine then." This cruising speed is actually the practical cruising speed of most bombers. With Gao Zhendong, an "aerodynamics expert," able to make this assurance, the comrades' worries were greatly reduced.

"If that's the case, then there's definitely potential!" The soldiers' eyes lit up.

Only then did Gao Zhendong point out the defects that the colleagues at Chongqing Aircraft Industry Group had not mentioned, because these were defects that they really hadn't considered.

"However, this aircraft still has some shortcomings. First, the structural design needs more attention. Although this aircraft has a large space, the load distribution is completely different from that of ordinary aircraft, and the stress concentration distribution area is also different from that of ordinary aircraft. This point must be fully considered during the design process, otherwise it is easy to cause problems such as wing breakage."

Gao Zhendong was grateful in his heart to the pioneers of the flying wing world, to the YB-49 bomber, which was the most complete test aircraft ever built. It was because of this that the wing broke and crashed.

When the comrades heard Gao Zhendong's words, they couldn't help but laugh. This problem is like a "first impression killer"—if you don't know it, you can easily fall for it. But once you discover it in advance, you can avoid or reduce the harm caused by this problem to a great extent.

“Comrade Zhendong, you have already identified this problem in advance. I believe that if we really want to do it, the comrades at Chongqing Aircraft Industry Group and other factories will not take it lightly.” Chief Engineer Wei smiled more broadly than anyone else.

The colleagues from Chongqing Aircraft Industry Group nodded in agreement: "That's right, Committee Member Gao, we really hadn't considered this problem, but since you've found it for us, we still have some solutions. Even if we use finite element analysis to calculate it segment by segment, it will take us a year or two to get these data solid."

Using finite element analysis to calculate load-bearing structures has become one of the most common design methods they use in their regional jets developed in cooperation with the French. Combined with their well-developed industrial design software, the results are excellent.

Besides, we still have your newly upgraded high-speed computer, which calculates even faster! Comrades are full of confidence.

Gao Zhendong couldn't help but laugh at himself, realizing that the problem was indeed true. "Another problem is that the aircraft's configuration has a major advantage, which is very conducive to stealth. It is easy to arrange the edges of the aircraft to be parallel, and the shape is very smooth, which is very beneficial to stealth design. However, this also brings a problem, which is actually related to the difficulty of handling - that is, the excessive smoothness leads to a lack of aerodynamic trim, resulting in poor takeoff and landing performance."

The Air Force comrades couldn't help but feel that Comrade Zhendong was really concerned about the pilots. Haven't they seen enough planes with poor takeoff and landing performance? At worst, they could just build a better and longer runway. If this plane were to be developed, it would deserve this treatment.

MiG-21: Are you talking about me?
However, the colleagues at Chongqing Aircraft Factory took it very seriously. Following Gao Zhendong's words, they realized that the poor takeoff and landing performance not only meant that takeoff and landing required high runway standards, but also implied poor takeoff and landing safety and susceptibility to external conditions.

"If we're going to do this, we'll give it full consideration!" they said very seriously.

"Well, this is just a matter of principle. If we really want to implement it, we can discuss the specific details in detail later."

In Gao Zhendong's view, if there is research experience in stealth fighters as a foundation, and the pursuit of stealth performance is not to reach the level of the B-2, then the biggest difficulty of this aircraft lies in the aircraft itself, not in stealth.

The main problem is that flying wings are still quite difficult for us now. Fortunately, the weapons that our comrades have now are not only superior to those of the 60s in our previous life, but also comparable to those of the 80s. So there is still some hope.

Besides aerodynamic design, the most crucial component is the fly-by-wire control system, which is essential for a flying wing to fly well.

The colleagues who were originally working on fly-by-wire go-around were already researching with the French on their large passenger aircraft project, and had accumulated a wealth of knowledge, experience, and achievements.

As for flying wing aerodynamics, Gao Zhendong can still find the fundamental principles and can be of great help in this regard.

"It's wonderful that Committee Member Gao is willing to take the time to follow up. We've never worked on this type of aircraft before, so we're under a lot of pressure." The colleagues at Chongqing Aircraft Factory were now treating this matter as something they were going to start, and the pressure was indeed there. They were overjoyed to hear that Gao Zhendong was willing to follow up on the technical details.

Gao Zhendong laughed: "Actually, you don't need to feel too much pressure. We still have some advantages and conveniences in our hands to get this done."

"There are advantages and conveniences?" To be honest, the comrades at Chongqing Aircraft Factory never expected this, as this area was almost completely unknown to them.

Gao Zhendong nodded: "There really is."

As he spoke, he analyzed the existing conditions he had just considered one by one, but aside from the fact that he could find the aerodynamic theory of flying wings, he couldn't say that.

The comrades listened with great interest, and the more they thought about it, the more reliable it seemed. They realized that we were already so powerful and had made so many preparations.

"Moreover, in addition to the above, we have another very good condition..."

"What conditions?"

"Although our high-sonic wind tunnel construction is still a bit lacking, we already have quite a few subsonic wind tunnels, and they are quite good. This aircraft is subsonic, so we have enough capacity to conduct more wind tunnel tests. If we don't have enough theory, we can make up for it with experiments!"

In the field of aerodynamics, theory alone will never be enough for half a century; only experimentation, and a great deal of experimentation, can solve the problems.

The current state of our wind tunnel construction is one of the reasons why Gao Zhendong doesn't even consider combining supersonic speed and stealth.

As long as it can be made invisible, subsonic speed is sufficient, and the testing conditions in a supersonic wind tunnel are far inferior to those in a subsonic wind tunnel.

Upon reflection, the comrades realized it was true!
One has to admire Comrade Zhendong; he took all the conditions into account.

The comrades were secretly delighted, examining the drawing Gao Zhendong had made on the blackboard. At this moment, the drawing had become a complete treasure in their eyes.

At this point, those who were interested in carefully examining the diagram began to see some clues and raise questions.

The intricacies are obvious: the parallel fuselage lines, the smooth exterior, the protruding belly and wings...

But there are also doubts.

"Committee Member Gao, is this air intake located on the back of the aircraft?"

"Yes. In order to cover the air intake and air duct, so that ground radar cannot see the air intake, it is very beneficial to stealth." As we all know, the treatment of the air intake is very important to the forward RCS.

"But this will affect the performance at high angles of attack, right? This structure has very low air intake efficiency at high angles of attack, as it is all blocked by the fuselage."

"This is a bomber, it doesn't need high angle-of-attack performance." Even the comrades from the Air Force Equipment Bureau could answer that immediately.

"But the early warning aircraft at higher altitudes can still see it, right?"

Even the comrades from the Air Force Equipment Bureau were dumbfounded; it seemed to be true.

Gao Zhendong glanced at the comrade, his eyes full of smiles: "Since it's already stealthy, there's no need for low-altitude penetration. If this aircraft flies to an altitude similar to or even slightly higher than the early warning aircraft, and at the same time makes proper adjustments such as serrated air intakes and S-shaped air intakes, the impact will be minimal."

The comrades in the Air Force Equipment Bureau wished they could give themselves a good talking-to, but they were still too limited, too narrow-minded.

"So the exhaust nozzle is also on the back of the aircraft?" the colleague from the heavy aircraft factory asked.

No wonder I always thought the engine nozzle looked weird. I thought it was because Commissioner Gao's drawing skills were too bad, but I didn't expect that he did it on purpose.

"Yes! This nozzle is on the back of the aircraft, which reduces the aircraft's infrared signature and lowers the infrared detection range."

Comrades stared wide-eyed. So, the stealth you're talking about isn't just about radar?
Seeing their expressions, Gao Zhendong explained, "With the development of technology, infrared detection range is also very long, so if we can handle it, we should."

(End of this chapter)