Chapter 1011 New request from Mr. Chang
For this kind of speech, and focusing on the immoral behavior after the big breath, the rest of the people in the conference room immediately gave a strong criticism in their hearts. attack.
That is to say, the elders sitting here are quite strong.
If you are looking for someone with a bad heart, after listening to the first half just now, you will probably need Suxiao Jiuxin Pills.
However, considering that Liang Shaoxiu advanced the project progress by half a year at a time, everyone was not really dissatisfied.
Suppress first and then raise, joy must still be the main thing.
Especially Guo Lin, as another chief designer.
As a replacement product that has absorbed many experiences and lessons learned during the development of the Air Police 200, the development process of the radar system of the Air Police 2000 can be considered straightforward.
Ground testing began even more than a year ago.
Even the rotatable radome encountered more technical difficulties than the radar itself.
However, no matter how realistic the ground simulation is, it is impossible to completely restore the situation in the sky.
Otherwise, Air Police No. 1 would not have been hastily dismounted.
It can be said that the entire Air Police 2000 project is mainly waiting for the platform.
The platform problem is solved and the finalization is not far away.
However, Guo Lin is a pure electronic engineer after all. Even if he has collaborated with Chang Haonan several times before, his research objects are mainly equipment such as airborne pods, not the aircraft itself.
In contrast, Wang Xiaomo, who has been exposed to some aircraft designs through Air Police 200, needs to consider issues more comprehensively.
"Comrade Shaoxiu, you just mentioned that the downwash airflow generated by the wing increases, resulting in a decrease in lift generated by the horizontal tail..."
"Although modifying the design of the radome can compensate Total lift, but the position of the radome and tail is different after all, and it is impossible to adjust the deflection angle. Will it affect the trimming of the aircraft and the pitch controllability? "
Compared to the Air Police 200? Almost only the impact of crosswinds and the structural strength of the T-shaped radome need to be considered. While the large disk expands the radar detection angle, it also brings a lot of aerodynamic troubles.
In particular, the C909 is inherently smaller than the Boeing 707 and IL-76, but the 10.5-meter radome is larger than the E3 and A50U.
"As for the trimming issue, while the radome provides lift, it is also one of the main loads of the aircraft. It can affect the lift center and center of gravity of the aircraft at the same time. We have specifically tested the balance of the flight platform under different flight attitudes to confirm the current The design will not have a negative impact on the aircraft trim. "
"As for the pitch controllability... because the impact of the downwash airflow is to reduce the relative angle of attack of the horizontal tail, and the pitching moment provided by the horizontal tail is generally the same. The angle of attack is negatively correlated, so unless it is in a very negative angle of attack attitude, the pitch controllability is almost similar to that of the C909 platform with a clean configuration, but it is even better at a positive angle of attack above 6°..."
Liang Shaoxiu said and released a highly restored model of the Air Police 2000 early warning aircraft:
"After calculation, after combining the radome, the net stability margin of the entire aircraft is still 10.7%. Although the data of the clean configuration is slightly lower, it will basically not affect the flight quality.”
At this point, perhaps because he felt that it was not rigorous, he added:
"At least it will not have a greater impact than the deterioration of directional stability..."
In addition to the body itself, the core of the aircraft's directional stability is the vertical tail, but after carrying an oversized plate, the stability effect It will definitely be affected.
Even though Liang Shaoxiu specially lowered the height of the radome by 15 centimeters, raised the vertical tail, and added a pair of tail fins, he still could not completely restore the driving feel of the C909 itself.
However, this is an unavoidable problem for all traditional configuration early warning aircraft.
Fortunately, the aircraft's heading stability is inherently redundant, and as a strategic support platform, the Air Police 2000 will rarely fly in extremely large inclination angles or sideslip angles, so it is not unacceptable. .
"Mr. Liang, when can we start the flight test?"
After Liang Shaoxiu finished answering Wang Xiaomo's question, Guo Lin, who was sitting opposite, could no longer restrain his eagerness to try——
< br>Although he has served as the person in charge or chief designer of many projects before, those were basically small jobs.
Even the air-drying 200 pod back then was not at the same level as today's early warning aircraft in terms of the level of attention it received from its superiors.
It can be said that as long as the Air Police 2000 can be delivered on time, Guo Lin can firmly occupy the position of "successor of Academician Wang Xiaomo".
"Now that the overall design plan has been basically determined, the next step is to do wind tunnel testing..."
Liang Shaoxiu replied:
"But we have... uh... developed it by Mr. Chang It’s a set of methods, so the time for blowing the wind tunnel will not be particularly long. If nothing else happens, it will probably be completed before the end of the year..."
Although Chang Haonan's identity has now become that of the friend next door. Leader, but the experience and standards he left behind in the aviation industry system still play a role.
By locating the performance boundary as soon as possible, and on the premise of ensuring the reliability of the test results, the wind tunnel test plus flight test cycle can be roughly shortened to about half of the original time.
After hearing this answer, Guo Lin finally breathed a sigh of relief.
Fortunately, it was within his expectations.
But Liang Shaoxiu’s next words made his heart hang in the air again:
“The biggest problem at present is the platform itself. The first C909 aircraft responsible for the final assembly of Hufei Group has just landed. According to the initial plan, they will deliver a mass-produced aircraft to us as a modification platform before the end of next year, so they may not be able to keep up with our accelerated progress..."
This time, not only Guo Lin, but also Wang Xiaomo frowned slightly.
It would be a pity indeed if everyone's efforts to meet the schedule were wasted because of waiting for the delivery of the aircraft.
After thinking again and again, he turned to look at the leader of the General Armament Department next to him:
“Can you consider coordinating with the relevant units and deliver us a Tupolev aircraft first? Picture 214K of the final assembly, at least let the prototype fly?”
Picture 214K, where the K stands for Китай. That is, Figure 214 is designed and manufactured in accordance with China Aviation Industry Standards.
Used to distinguish it from the earlier Figure 204/214S produced with Russian standards.
There is almost no difference between the two models at the aerodynamic and structural levels, except that the former has been equipped with a two-person cockpit and a new avionics system.
So much so that in order to improve production efficiency and worker training efficiency, Tupolev finally stopped the old model production line. Instead, Tiangangdi began to deliver to Aeroflot, which was produced according to the Figure 214K standard. airplane.
As a result, Aeroflot, which had already begun to adapt to Airbus and Boeing models, quickly expressed that it was really good, and even had a tendency to force the Russian standards to move closer to the Chinese standards...
According to the According to the original supply contract, before the domestic version is delivered to China, several airlines such as United Airlines that plan to purchase C909 will also receive a small amount of Tu-214K first to conduct adaptive training for pilots and ground staff.
It shouldn't be difficult to take one out and give it to the Haofei Group.
Sure enough, although the leader of the General Armament Department did not immediately give a clear response, he also said that he would make an application to his superiors after returning.
Even if we cannot deliver ready goods, we can at least ensure that one of the next batch of aircraft delivered within the year will be used as a transformation platform...
...
About aircraft design The discussion finally comes to an end here.
As for the radar part that Guo Lin is responsible for, there is actually no need to make any progress since last month.
Only routine boot test records.
Reports can be submitted regularly, and there is generally no need to report them specifically at a seminar.
But today, after Liang Shaoxiu’s report, Wang Xiaomo did not immediately announce the end of the seminar.
"Xiao Guo, please wait a moment."
As he spoke, he took out a file bag from his briefcase and handed it to Guo Lin, who had already started packing his things:
“A brother unit proposed to us a new test on the Air Police 2000 airborne equipment. Please take a look."
The other party's description made the latter's eyes flash with surprise:
"A test request from a brother unit?"
Generally speaking, When it comes to major core projects, we will try our best to avoid unnecessary complications midway.
At present, the airborne equipment of Air Police 2000 has almost completed ground testing. It is definitely not something ordinary people can do to incorporate new functions or technologies at this juncture.
With such doubts, Guo Lin took the file bag and opened it.
Inside is a document that is not too thick.
The first thing that catches the eye on the cover is a line of large characters -
"Feasibility Test of Application of Network Coding Technology in Airborne Data Link Communication System"
"Are we going to build an airborne data link?"
Guo Lin had an expression on his face like "Why didn't I know about this?" He was about to raise his head to ask Wang Xiaomo about the specific situation when he accidentally glanced at the proposal at the bottom of the cover. Unit——
China Aerospace Power Group.
“Huh…”
All the confusion just now was gone in an instant.
"That's not surprising..."
Guo Lin thought to himself.
He quickly opened the document, which briefly introduced the installation of an additional data transmission antenna on the Air Police 2000 to realize real-time information interaction between the early warning aircraft and the forward fighter.
Of course, currently it can only be done through direct transmission or ground relay transmission, so the effective range is limited.
However, this test is to prepare for the future launch of high-throughput communication relay satellites, so satellite transceiver antennas will be reserved at the hardware level.
As for fighter jets...
The new batch of J-10A and J-11B will also be equipped with the same antenna, while the old batch or old model can temporarily solve the problem with a pod.
"So... our 14th institute needs to integrate the search information of the early warning aircraft radar into this airborne data link communication system?"
Guo Lin raised his head and asked tentatively .
“That’s right.”
Wang Xiaomo nodded:
"Although I also think that relying on ground stations for data relay... there may be too many intermediate links, but Comrade Haonan said that he has a way to solve the high problem caused by multiple relay nodes. We don’t have to worry about transmission delays and low transmission rates.”
“In addition, this system is currently only required to be one-way, which is to transmit the information from the early warning aircraft to the fighter jets for reception. For you 14. It shouldn’t be difficult, but the complete form in the future will definitely require two directions.”
“Based on my understanding of Comrade Haonan, I suggest that you make a plan in advance, preferably in one step...at least to stay. There is room for upgrading the two-way data link, otherwise I am afraid that if I wait a few more months, his plans will be advanced again..."
(End of this chapter)