Chapter 792: Early Warning Aircraft Needed

A roll rate of 140° per second is not an astonishing figure if placed within the entire range of a fighter jet.

The distant F16 Mirage 2000, the nearby J-10 and Rafale all far exceed this number, and the high ones can even reach more than 300° per second in the net configuration.

However, it is obvious that these aircraft are designed to be highly agile.

For a heavy fighter that is not good at this - in fact, it has always been a shortcoming in the past, this number has improved quite significantly.

And all of this was recorded by the J-11AS flying slightly behind.

"1121, your roll is very fast and smooth, with almost no loss of height. It's very good."

Even for top test pilots, a break is needed between two test flight subjects, so the two aircraft in the sky are taking advantage of this time to make radio contact.

"I feel that this has not yet reached the limit of the aircraft's strength, but I am afraid that flaperons alone will not be able to provide a higher rolling moment."

Fu Guoxiang's voice was mixed with a slightly rapid breathing:

"I'll turn 180° first and try increasing the speed by 100 degrees."

At the same time, as the first rolling test ended, there was a burst of applause inside the tower.

Although today's wireless data transmission efficiency does not support processing high-definition images, by integrating an additional set of antennas and sensors inside the prototype, some basic flight data can be transmitted back to the tower in real time.

This improvement is actually dispensable for a smooth test flight, but if there is any malfunction or even an accident during the test flight, it may become the key to solving the problem.

Although this kind of thing has not happened for several years, everyone still has to keep this string in their hearts.

If aviation safety is relaxed even a little bit, there is a high probability that it will be a landslide.

"Mr. He, it seems that your body structure upgrade has been very effective."

Chang Haonan looked at the flight parameter curve displayed on the screen in front of him, and his tone became much lighter.

Although He Ming next to him looked as calm as water on the surface, the corner of his mouth that was suppressed by the general when he spoke still revealed his inner excitement:

"We have actually determined the effect of the upgrade of the airframe structure before. Now that we can implement this theoretical effect, we have to thank you, including Mr. Chang, for providing us with new technologies and new processes for Project 11."

Of course, his statement is not entirely false.

The Su-27SM, which uses the same airframe next door, made its first flight more than half a year ago, verifying the effectiveness of this configuration.

In addition to the improvement in structural strength, the flight control level has lifted the restrictions on roll. More importantly, the length of the flaperons in the new configuration has been significantly increased, almost occupying the entire trailing edge of the wing, so it can be more actively operated. Participate in the roll.

But the design is the design, and the object is the object.

Otherwise, the planes built by Stan Aviation would not be so uncomfortable.

For China, which has just figured out how to build the basic model Su-27SK, it is already very rare to have no problems after a major structural and process upgrade.

"Actually, Lao Fu feels that there is no problem. In terms of structural strength alone, this aircraft actually has a lot of room for improvement. I heard that Sukhoi is working on installing the AL27FU on a Su-31SM prototype. Let's try it. Where is the limit?”

AL31FU is the engine used by the No. 711 technology demonstrator. Compared with the AL31F, it has increased thrust and, more importantly, has thrust vector control (TVC) capabilities.

The Flanker's body is inherently large, and the two engines are installed far away from the central axis, so the moment of inertia is very large.

In the past, the main factor that restricted the increase in roll rate was structural strength, so this problem was not very obvious.

Now, as Fu Guoxiang said, flaperons alone can no longer meet the requirements.

However, everything has two sides.

If a TVC nozzle is installed, then what was originally a simple burden can provide rotational torque in one turn.

In this case, the engine is located far away from the centerline, which actually becomes an advantage.

"Just take it one step at a time."

Chang Haonan put his hands behind his back:

"After the turbofan 10 is completely finalized, upgrading TVC capabilities will definitely be put on the agenda."

Thrust vector is not necessarily of much use.

But something is better than nothing.

For a high-thrust engine, the thrust-to-weight ratio will not be lost much, and the TVC nozzle will not consume life when it is not working.

As long as you use it once, you will earn blood.

However, the priority can indeed be moved back a bit.

After all, China has never accumulated technology in this area in the past.

A rotatable nozzle itself is not difficult. What is difficult is writing this thing into the flight control.

He Ming didn't press for it, he just mentioned it in passing, so the attention of several people quickly returned to the display screen.

After the first test, Fu Guoxiang conducted several more tests in the transonic range with steps of 100km/h.

As the speed increases, the efficiency of the wing's outer flaperons will decrease, so the roll rate will inevitably be affected.

However, even at the lowest speed of 1350km/h, it still maintains a level of about 60° per second, which is far higher than before the improvement.

"It seems that the four simulated mounts brought with it do not have a great impact on the performance of the aircraft..."

He Ming touched his chin and nodded, obviously very satisfied with the test results.

"This is also the inherent advantage of Su-27."

Chang Haonan replied:

"When Project 601 was just started, also studied whether to consider setting up a conformal fuel tank between the two engines to further extend the range. However, after later research, it was found that the gain outweighed the loss, so you have not seen this plan. A set of aerial oil receiving devices has been added.”

The Flanker's fuselage puts the best pylon location between the two air inlets in the middle of the fuselage. This is a low-pressure area, so the resistance is very small. Generally, large-size ammunition is hung here instead of under the wings.

If four mid-range bombs of the size of R77 or Thunderbolt 12 are mounted in parallel, the impact on flight performance will be almost negligible.

While the two were talking, the data on the screen also showed that prototype No. 1121 began to slow down and returned to level flight.

Today's test content has been completed, and it is time to return.

"Mr. Chang, according to the current progress, the basic flight performance test will probably be completed soon."

He Ming suddenly said:

"The next step is to wait for the delivery of the PL-12 and PL-13 test bombs, and then conduct the testing of the airborne avionics and fire control systems."

"The PL-12 should be fine. The 1493 radar itself can cover the entire envelope. But if we want to test the PL-13, we may need an early warning aircraft to provide additional target information at a longer distance."

Compared to TVC, which was just mentioned casually, this matter is indeed more important.

This is true both for the Thunderbolt 13 and the entire Chinese Air Force.

"We can no longer count on the ring project. I heard that the David Kingdom has even started to ban technicians from the 14th Institute of Electrical Engineering from approaching the aircraft."

Chang Haonan put on his coat and walked outside, preparing to greet the triumphant test pilot, and said to He Ming who was following half a body behind:

"However, the Air Police 200 that first flew at the beginning of the year has now been equipped with a real radar array. If no major problems are found in the electronic equipment and data link, it will definitely be able to catch up with your test firing and target practice."