The Goddess Shines on America

There is no doubt that YF-22 is the predecessor of F-22.

The F-22 Raptor fighter jet was jointly developed by Lockheed Martin and Boeing. It is the world's first single-seat, twin-engine, high-stealth fifth-generation fighter jet. It entered service in the US Air Force in the early 21st century to replace the fourth-generation fighter jet. The main model of the F-15 Eagle fighter.

In this project, Lockheed Martin is the main contractor, responsible for designing most of the airframe, weapons system and final assembly mitigation, and program partner Boeing provides the wings, rear fuselage, avionics integration system and training system. At least as far as Alice knows, that's how they should be divided.

It's just that the current actual situation has somewhat deviated from her memory, that is, the avionics system is also in charge of Lockheed. Of course, this kind of situation that would appear as long as there was a slight deviation in the negotiation process, of course, would not surprise Alice. Compared with knowing the comprehensive details of the entire project, this subtle difference is nothing to worry about.

At present, what Joseph, the person in charge of the project, introduced is the relevant data of the product they are currently using for bidding, YF-22.

First of all, this new type of fighter, which is planned to be a fifth-generation fighter, is designed with a maximum speed of Mach 2.4, a maximum ceiling of 200,000 meters, and a combat radius of about 650 to 700 kilometers. As for its weight, in principle, the lighter the better, but as a representative of heavy fighters, its maximum take-off weight is still as high as 22 tons.

"During the development process, we drew heavily on the technology and experience of the F-117A, because its stealth performance is very good. At the same time, we also paid attention to overcoming the airframe composed of multiple inclined cones, and the unsatisfactory aerodynamic performance of the cockpit. The resistance is too high, and it can only fly at subsonic speeds.”

Having said that, seeing Alice just nodding, Joseph couldn't help but stop.

"May I ask, Alice, although you are an expert in the field of computer programming, but in terms of aircraft development...do you understand what I said?"

In order to avoid wasting effort and to better organize the next language, Joseph felt that it was necessary for him to ask.

"Of course I understand."

Alice could guess what Joseph was hesitating, and said with a smile: "I taught myself college physics when I was ten years old, and what's more, what you are talking about now is not particularly professional. Please continue."

Seeing that Oren also nodded to himself and smiled slightly, Joseph had no choice but to continue talking.

"So, based on the shape of the F-117, we designed the nose of the YF-22 into a pyramid shape. The two air intakes are installed along the lower slope of the pyramid. The air intake section is a parallelogram, which is different from conventional aircraft. However At this point, we need to make a trade-off, although the stealth effect of the air intakes under the wings is far less good than that on the wings, it is very beneficial to improve the maneuverability of the aircraft at high angles of attack."

"This is the problem of the nose and air intake. As for the wing, we have adopted a large root-to-tip ratio, that is, a trapezoidal wing with a large root-to-wing tip ratio. The leading edge sweep angle is 48 degrees, and the trailing edge The sweep angle is about 17 degrees. Choosing such a wing is conducive to highlighting and improving the maneuverability of the aircraft, improving the supersonic cruise capability of the aircraft, and meeting the needs of stealth. At the same time, in order to reduce the interference between the horizontal tail and the vertical tail, We designed the twin vertical tails to be tilted out only 27 degrees, which is ... very small."

Whenever there is a technical term in the tunnel, Joseph carefully adopts a more intelligible statement, and carefully observes Alice's expression, for fear that she will appear confused or pretend to understand.

Fortunately, he was relieved that the girl who appeared out of nowhere seemed to really listen. It can be seen from the eyes that she is really thinking about her introduction, rather than pretending to be deep.

"As for the pilot's cockpit, we set it as a bubble type with a good view. At the same time, the rear edges of the flat tail, tail brace, binary nozzle and tail cone all have irregular jagged shapes, which are mainly for the scattering from the air. Enemy radar waves coming from behind."

"In terms of power source, we plan to adopt thrust vectoring nozzle technology, so in terms of cost..."

"Sorry to interrupt."

Alice raised her hand and said, "Please explain to me, what kind of technology is this thrust vectoring nozzle?"

Just ask if you don’t understand, this kind of behavior can’t help but make Joseph more at ease, and every engineer present can’t help but breathe a sigh of relief. Not bad, not bad, at least judging from the current situation, this girl who was suddenly invited into the house by the boss would be an excellent partner.

"Thrust vectoring technology refers to the thrust component generated by the engine thrust through the nozzle or the deflection of the tail jet. Adopting this technology can replace the control surface of the original aircraft, or enhance the control function of the aircraft, and can control the flight of the aircraft. real-time control."

There is no doubt that military aircraft research and development is a project that integrates technologies in multiple fields, and when countless technologies are all concentrated on a single aircraft, each seemingly unrelated combination has an inseparable relationship with each other. relation.

From the shape of the aircraft, the reason for the design of the shape, to the specific parameters of the aircraft and engine, and what technology the engine adopts, all this information will be closely related to the airborne avionics system. It is conceivable that if the person who writes the system does not understand the performance of the aircraft, his work will not be suitable for this aircraft at all.

Therefore, the atmosphere of this meeting became more and more relaxed as Alice raised questions one after another.

"The specific impact of this control...could you please elaborate a little bit?"

"It is to turn part of the thrust of the engine into the control force."

Joseph answered her frankly: "This method can greatly reduce the radar reflection area. At the same time, no matter how large the angle of attack is and how low the flight speed is, the aircraft can use this part of the control force to control, which increases the maneuverability of the aircraft. sex."

"Also, since the control force is directly generated and variable in magnitude and direction, which increases the agility of the aircraft, we can also appropriately reduce or eliminate the vertical tail. Obviously, the fewer parts, the more The harder it is to be detected by radar, it can also reduce the resistance of the aircraft, reduce the weight of the structure, and even reduce the cost."

From each design of the aircraft to the specific reasons for each design, Joseph gave Alice the most detailed introduction to every detail of the entire aircraft without comparing any documents. All in all, it took him an entire hour just to summarize these contents.

The real time of the whole meeting was much longer than this. Whenever Joseph mentioned some key points, Alice would ask very targeted questions. Furthermore, as the number of questions continued to increase, the frequency of eye contact among the 30 people in the audience became higher and higher.

Alice didn't mention any of the obvious questions, and every question she asked was very insightful, and it often required Joseph to give a long speech to explain it clearly. And in the whole process, a very strange situation was gradually discovered by everyone.

At the beginning, Alice was puzzled by some very critical and unusual technical terms, such as the "thrust vectoring technology" that was first asked. But as the introduction continued, Alice's questioning gradually changed from an incomprehension of nouns to a rhetorical questioning attitude.

"Why this angle? Isn't that angle better?"

"There must be a relationship between the area of ​​the engine blade and the thrust, right? If it is too wide or too narrow, there are gains and losses. What we need to do is to take the middle amount, right? Well, since this engine adopts this size to achieve this effect, that size Is that the effect, if you use this size, will it be better?"

These questions seemed to be asked casually, but there were a total of thirty people present, and Joseph was the only one who kept asking. When he kept saying these familiar information, others who had nothing to do couldn't help thinking about it. Alice's point of view seemed very reasonable.

Even Joseph himself, facing Alice's question after question after question, became more and more stupefied.

Why this angle and not that one?

Neither this area nor that area will work, so what about this area?

It seemed like it was just a random number, but when the thirty people present thought about it carefully, it seemed that this number... was the most appropriate number!

The meeting officially started at 9:30. When the time was close to lunch, the question-and-answer relationship between Joseph and Alice had quietly changed.

"Let's talk about stealth coatings, you ask me if there is any way to reduce costs, right? The direction of nano coatings is right, but are you too obsessed with elements that look expensive? Think about diamonds, but Changing the order of the carbon atoms can form such a strong substance. If we can find a relatively cheap substitute for something as expensive as stealth paint, wouldn’t it be the best price reduction range?”

"Don't, don't talk to me about making money. I don't understand small profits but quick turnover. Based on the paint you told me, the final cost of this aircraft must exceed 100 million yuan, plus various post-production costs. It costs three or four hundred million! At such an expensive price, selling one or two is a big profit, but only one or two can be sold!"

"Quickly give me a try with that element! That's right, that element, oh, don't be obsessed with your element, please read your chemistry book, okay? The refining process of my element is twice as cheap as yours. , use my element, and then try it as a substitute, I don’t believe the cost can’t come down!”

At the end, Alice patted the table angrily, as if Joseph was a primary school student who couldn't even add one plus one. Why didn't he find such an obvious answer?

Yes, why didn't I find out?

Joseph thought about Alice's suggestion with empathy. It seemed, seemed, almost, that the element she proposed could really be used as a cost-reducing substitute.

So, creativity and inspiration are really so disgusting sometimes.

Knowing is knowing, not knowing is not knowing.

Why didn't I think of it myself?

Joseph was really upset.