Chapter 647 Flanker Evolution (Page 12)

First flight test, everything went well.

The triumphant Song Shangcai was naturally welcomed as a hero.

After all, no matter how much effort the designers put in on paper, it is the test pilots who ultimately bear the huge risks on the front lines.

The leaders of the Turbofan 10 and J-11WS projects took turns to hug him.

However, when it was Chang Haonan's turn, Song Shangcai, who was still holding a bouquet of flowers in his arms, did not leave immediately after the usual greetings, but said:

"Mr. Chang, after climbing to 16000 meters just now, it was really difficult to control the aircraft. It was still barely able to fly levelly. As long as I made a slight movement, the nose of the aircraft was completely out of control..."

Although generally speaking, no matter what decision a test pilot makes in the sky, he will not be questioned, but after all, he only completed half of the test mission due to his own reasons, so he felt that it was necessary to explain the situation a little bit.

Chang Haonan's mentality at this time is quite good. After all, the Turbofan 10 is not just a single project, but the key to breaking the situation.

The subsequent domestically produced and upgraded J-11B, as well as the new J-10 that has been changed beyond recognition, all need this model as power.

Now the flight test is going well. Although there are still many subjects that need to be completed in the follow-up, we can already look forward to a new round of upgrades of the Chinese Air Force's main combat equipment.

It’s a pity that the J-8C has only been Little Tiantian for two years now. I’m afraid she will become Mrs. Niu in another two years...

So he waved his hand very simply:

"It doesn't matter. Test flight is an uncertain process to begin with, and the plan was made to break it."

"Furthermore, the fundamental reason why this test flight was not completed is that the performance of our engine is too good, and it is not a shameful thing. If you have the opportunity to write a memoir or something in the future, just remember to describe this matter in detail."

Chang Haonan's joke caused a burst of laughter around him.

Even Song Shangcai was obviously relaxed.

After all, it was not dinner time yet, so after a brief welcoming ceremony, everyone quickly got back to work.

Technicians from Factory 112 towed the aircraft back to the assembly workshop and conducted structural inspection after the first flight to confirm that the aircraft did not suffer any invisible damage.

Engineers from Institute 601 responsible for writing flight control programs, together with Chang Haonan and others, are waiting to obtain test flight data and analyze and improve possible problems——

The combination of digital fly-by-wire and flight-propulsion integrated technology is the standard configuration of the next three and a half generations of fighter jets. Therefore, while serving as a turbofan 11 demonstrator, this J-10WS is actually responsible for the verification task of the flight control system.

One flight meets the requirements of three project teams.

It can be said that the price/performance ratio is excellent.

……

After a simple lunch, the test flight data obtained from the flight recorder was imported into the computer.

From a qualitative point of view, the performance of the turbofan 10 on the aircraft is almost completely consistent with the simulation test results of the high-altitude platform.

However, quantitatively, after the engine change, the performance of the J-11's inlet did exceed Chang Haonan's expectations, so much so that at high altitudes and subsonic speeds, the thrust performance of the turbofan 10 was even better than expected.

"No wonder the test pilots responded that it was difficult to control the aircraft at an altitude of 16000 meters."

Liu Yongquan, who has been working as Chang Haonan's deputy, pointed with a pen at the thrust curve on the curtain:

"In fact, at an altitude of 14000 meters, the thrust data of the AL31F began to decline significantly."

"At 16000 meters, 1.4 times the speed of sound, the thrust has dropped from 12.5 tons to about 10.7 tons, while the thrust of the turbofan 10 has only dropped from 14 tons to 13.5 tons, a difference of 25%, and the automatic The trimming system is turned off and is purely controlled by hand. To be able to fly stably and level is considered a bold move for an expert..."

"Further back, after turning off the afterburner and ending the test state at the same time, the gap between the two engines in the intermediate thrust state is even larger. Therefore, under the automatic operation of the flight control system, the turbofan 10 passes by about 30%. The rotational speed has achieved a thrust balance with the right engine, which is also close to the situation reported by the test pilot comrade."

Immediately afterwards, Liu Gaozhuo, deputy commander-in-chief of Project 11, who was responsible for the design of the flight control system, changed to another slide:

"The data recorded by the flight control system also shows that when the pilot's action of adjusting the throttle opening is 0, the average time for the turbofan 10 to start responding is 0.53 seconds, while it is 31 seconds for the AL0.97F."

"Furthermore, in terms of thrust adjustment speed, the former is on average 55% faster than the latter. In other words, it only takes half the time of the latter to complete the entire thrust change process."

"However, it is worth noting that the advantage of the turbofan 10 over the AL31F in terms of thrust response is that the greater the speed and altitude, the more obvious it is, and it is more obvious when pushing the throttle than when closing the throttle. If it is in the low-to-medium speed section below 6000 meters, even It may be overtaken by the latter, of course, this will not be determined until we conduct mid- and low-altitude tests in no-man’s land.”

At this time, Chang Haonan took up the conversation:

"This is normal and has little to do with the flight control system. In order to reduce the structural complexity of the turbofan 10, the ejection nozzle itself has a weaker adjustment ability at low altitude and low speed than the convergent expansion type. It's hard to give up. Well."

"As for the remaining conclusions, let me briefly summarize them..."

"..."

After briefly summarizing the results of the first test flight, he paused and then talked about another topic:

"According to the current schedule of the plan, after the Spring Festival, we can start flight testing with the twin-engine turbofan 10 and complete all the envelopes that cannot be done in the single-engine state."

"If nothing unexpected happens, by the second half of this year, both models of turbofan 10 will be able to provide products to two models of third-generation aircraft in the form of small batch trial production. I don't know the upgrade progress of the J-11 on Mr. Liu's side. How far have we come?"

If others were to tell you that it only takes one year for an aero engine to go from bench testing to small batch trial production, no one would take it seriously.

But since these words came from Chang Haonan's mouth, everyone couldn't help but ignore them.

Therefore, Liu Gaozhuo, who was sitting opposite, replied with a serious face:

"Together with the engineers from Sukhoi, we increased the use of composite materials in the skin part. While reducing the empty weight, we also allocated part of the weight to the structural parts. Combined with a more detailed flight control system, it was basically relieved. The overload usage limit of the aircraft in a specific speed range."

"A set of heavy-duty hardpoints have been added to the inside of the wing, increasing the total number of pylons to 12. However, the load-bearing capacity of these two hardpoints is currently only 2000kg, which is still not as good as the two unlimited weights located on the belly of the fuselage. Hang on..."

"In addition, by dynamically adjusting the sequence and distribution of fuel during flight, effective control of the aircraft's center of gravity is achieved to a certain extent, and the flow of the fuel cooling system in the nose part is also increased."

"Although the effective diameter of the aircraft head is reduced from 1000mm to 930mm, the heat dissipation power is increased by nearly 200%. In the future, there will be sufficient conditions to install higher-performance flat-panel slot antennas and even electronically scanned antenna radars..."