From the moment he sat in the cabin just now, Fu Guoxiang was already looking forward to the test flight of the high-altitude and high-speed subject.

As a test pilot, when he was preparing for the ground, he naturally looked at the performance report of the aircraft.

The new engine shown above for the prototype 04 was significantly improved at an altitude of more than 20,000 meters.

Among other things, the usable thrust alone has increased from less than 4 tons to about 6 tons.

50%!

In general, the performance of an aero engine decreases as the flight altitude increases due to changes in factors such as air density, temperature, and oxygen content.

This situation will be even more pronounced at altitudes above 10,000 meters.

Sea level thrust is a data that can be used as a reference for the performance of aero engines, but it may not be of much value.

It is nothing new that two engines with similar thrust on paper have twice the difference in performance parameters after they are installed and lifted off.

The original Turbojet 14 is clearly a model that is not so optimistic in practice.

As an interceptor, the J-8 naturally tends to optimize the high-altitude and high-speed areas.

But this "optimization" is relative.

It can only be said that compared with other aircraft equipped by the Huaxia Air Force at the same time, the J-8 has better high-altitude and high-speed performance.

But when compared with their counterparts in other countries, the results are not very optimistic.

For example, as the most important performance of the interceptor, the maximum speed of the J-8 and J-8B is actually only 2.2 times the speed of sound.

Not to mention that compared with monsters like the MiG-25, which have flown more than Mach 3, even the F4 and MiG-23, which do not take volleying as their main mission, are stronger in this data.

What's more, due to the power response problem mentioned earlier, fast speed does not mean fast acceleration, and the overall performance of the original J-8 at high altitude is still relatively clumsy.

As a simple missile launch platform, it is barely enough, however......

Until now, the only missiles that Huaxia can use for the J-8 are the more than 50 Aspides imported from Italy.

In fact, Fu Guoxiang is one of the few people in the Air Force who still think it is necessary to equip the new model of J-8 aircraft after learning of the existence of Project 10 and Project 11 -

Before joining the test flight unit, he had served in the Air Force of the Rongcheng Military Region for a long time, and successively flew two models, the J-6 and J-8I.

Due to the peculiarity of the geographical topography in this direction, the Huaxia Air Force has long been able to maintain a year-round presence at airfields below 3,000 meters.

Although the plateau radar station at an altitude of 5,374 meters has a superior field of vision, and can capture signals and issue early warnings almost at the same time as the target takes off, in the face of the MiG-25R reconnaissance aircraft equipped by South Asian countries, the J-7 that takes off from Rongcheng or Licheng is not even enough range, although the J-8I can pose a certain threat, but when it slowly climbs and then accelerates and flies over, it can often only eat the exhaust of two R-15 engines......

As a result, the other side's attacks and harassment actions have become more and more rampant for more than a decade, and sometimes they have even deliberately penetrated deep into the airspace to carry out provocations.

One of Fu Guoxiang's comrades-in-arms had an accident while trying to use the power jump tactic to break through the maximum ceiling and launch a missile, and finally had to leave the combat unit.

So today, after experiencing the surprise brought by these two new engines, he can't wait to fly to the speed and altitude that should belong to this aircraft and explore the limits.

……

"Ready to start testing the supersonic flight subject."

Fu Guoxiang repeated the command of the tower, and then, according to the past habit, slowly pushed the throttle valve with his left hand, and at the same time pulled the lever slightly with his right hand to let the plane enter a shallow climb state.

He noticed that the tachometer needle response was still the same as it was on the ground.

Any action of the throttle valve is reflected in the thrust change of the engine in a very short time.

Moreover, it can be seen from the instrument status that even at the moment when the afterburner starts working, the various data of the engine are still maintained within a relatively stable range.

This gave Fu Guoxiang great confidence.

In the case of the previous prototype No. 04, in order to ensure the stability of the engine working state, the process of the throttle valve from the middle thrust to the maximum thrust needs to be controlled around 20-30 seconds.

But this time, he pushed the throttle almost twice as fast as usual.

"The throttle has been pushed to maximum thrust."

Fu Guoxiang's voice sounded in the tower.

It was only about 10 seconds after the order was given to him for supersonic tests.

There was a round of applause from the layman's audience, but it was interrupted by a wave from the elder.

"Don't disturb the comrades of the technical unit."

The command room fell silent again.

"What's the state of the engine?"

The test flight commander's voice was a little nervous.

He was also a test pilot before he was grounded because of his age, and he had participated in the test flight of the J-8B model, so he knew very well the skills of stabilizing the thrust and afterburner.

It was too short.

"Report to the tower, I have broken through the speed of sound, the current altitude is 11670, and all the data of the engine is very stable."

Fu Guoxiang's calm voice continued to come, but everyone could hear that he was suppressing his excitement:

"The dynamic response of the aircraft is much more agile than before, and it is ...... The thrust is also stronger at the current altitude, and my speed gains are very fast! ”

Before the official test flight, everyone involved in the test flight will go through a number of briefings to understand the theoretical data of the aircraft.

On the one hand, however, the results obtained through calculations and simulations often do not correspond to the actual situation.

On the other hand, many properties are difficult to quantify on paper.

Therefore, the situation reported by the test pilot is definitely beyond most people's expectations.

However, while everyone was still digesting what had just happened, the prototype 04 had reached a new point of speed and height.

"The current altitude is 16500, and the meter speed is 1850."

That is, it broke through 1.5 times the speed of sound.

Although the test flight will be tracked by radar throughout the flight, ground-based radar can only give the ground speed of the target, and the more valuable data for an aircraft is the airspeed.

So in general, the data will still be based on the pilot's report.

For more advanced flight test systems in the future, the ground tower can detect the status of the aircraft in real time, but at this time, detailed flight test data can only be obtained after the aircraft returns home.

Fu Guoxiang in the cabin had already left the sound far behind him, and in front of his eyes, the number displayed by the speedometer had come to 2480, and it was still increasing at a very fast rate.

The plane had reached similar speeds in past test flights, but by that time it was already very difficult to continue accelerating.

"Height 20500, watch speed 2590."

This is the theoretical maximum ceiling and speed of the old J-8 in the past.

In fact, on any aircraft, both of these indicators cannot be met at the same time.

That is, prototype No. 04 is far from reaching its limits.

"Please continue the test flight!"

Fu Guoxiang finally experienced the performance of a real interceptor!

……

This request made the commander in the tower hesitate for a moment.

Although the No. 04 prototype cannot be regarded as the "first flight" of the whole world, it has only been replaced with a new power system after all, and it is actually responsible for the task of carrying out flight tests on the carrier aircraft platform of the turbojet 14.

It stands to reason that this first ascent to heaven should not be too extreme for testing.

Not to mention that there are leaders who are visiting.

Even the current altitude of 20,000 meters and the speed of Mach 2.2 have exceeded the original test flight plan.

However, according to Fu Guoxiang's report, the current altitude and speed should be far from the limit for this aircraft, and according to the results of previous high-altitude and air-platform tests, there is indeed potential for further attempts......

After a few seconds of entanglement, he looked back at Yang Fengfa and Chang Haonan who were waiting behind him.

"Let's check how well the plane's systems are working at the current altitude and speed." Yang Fenghata stretched out a hand and pressed it on the back of the commander's seat:

"In particular, it's important to see if the engine has a stable power supply."

Fighter jets need to consume a lot of electrical energy during flight and combat, and under normal conditions, the IDG generator driven by the main engine will generate electricity.

However, after all, the engine has a limit, and the total power that can be provided is so much, if the aircraft is allowed to fly close to the limit for a long time, or the engine is not stable, there may be a shortage of power supply.

Later generations of F35 fighters have been plagued by this problem, unable to maintain the equipment on board at the same time running at full power, until Chang Haonan was reborn did not hear about the solution.

Therefore, if the power supply can still be maintained normally, at least it means that the engine is still in a relatively comfortable working state.

The command command was quickly issued to Fu Guoxiang in the air.

As a full-state prototype, the No. 04 machine naturally has a 1471G radar installed on it.

Compared with the J-8B, which is essentially a 208A single-pulse radar that is changed from a ranging radar, the performance of 1471G is much better.

This is the first X-band airborne pulse Doppler radar in Huaxia, which for the first time has (at least theoretically) the ability to look downward, and can guide semi-active radar-guided missiles to carry out over-the-horizon attacks.

In any case, it is a meeting for such an aircraft as the J-8.

However, at the cost, the power consumed by the radar is also much higher than in the past.

"The radar has been energized and the self-test has been successful."

If the radar is turned on at an altitude of 20,000 meters, if a target aircraft is not specially set up, it will naturally not be able to search for anything, but as long as it can work normally, at least it means that there is no problem with the power supply.

Chang Haonan and Yang Fenghat, who heard the news, glanced at each other, and their faces were also happy.

Compared with the aircraft fuselage and aviation power, which were completely designed and tested by their hands, the 1471 series radar developed by the 14th Electric Science and Technology Institute is a factor that is not completely controllable.

But this time, since the self-test can be completed at a height of more than 20,000 meters, it means that at least there is no problem in the foundation.

As for the Thunderbolt-11 air-to-air missile......

Strictly speaking, airborne weapons do not belong to the content of the 83 Project.

However, judging from the current situation, it is really possible to encounter a situation of "organic bullet-free".

Of course, these are all afterthoughts, and the meal must always be eaten one bite at a time.

The problem of missiles is not something that 601 can solve, and it is imperative to continue to complete test flights.

"It is allowed to continue the test flight, but it must be guaranteed that the maximum speed cannot exceed 2900."

Chang Haonan bowed his head and said next to the tower commander.

According to his simulation calculations of the performance of the J-8-3 after the rehairing, it is no longer the power factor that limits the maximum speed of the aircraft, but the fuselage.

When the aircraft flies at supersonic speed in a dense atmosphere, the friction with the high-speed airflow will cause the surface temperature of the aircraft to rise sharply, resulting in the weakening of the structural strength and stiffness of the aircraft materials.

For the airframe structure of the J-8-3, which uses aluminum alloy as the main material, Mach 2.5 is basically the ultimate speed to ensure flight safety.

If you want to continue to break through, then you have to put a lot of effort into the body materials.

For example, the MiG-25 uses a large number of VNS-2 high-nickel martensitic steel and VNS-5 high-molybdenum and high-nitrogen austenitic steel, which can be called black technology at that time, and its material density is more than three times that of aluminum alloy, so it is almost equivalent to a T72 tank flying in the sky when it is full of fuel and ammunition.

The more exaggerated SR71 uses a lot of aerospace titanium alloy, also at the cost of the material's ductility problems, which keep leaking until the aircraft is "heated" to its normal state.

In short, even if the cost and technical difficulty are not considered, for an aircraft like the J-8-3 for the 21st century, there is no need to pay too much price in order to break through 2.5 times the speed of sound.

When the speed of the plane came to 2800, Fu Guoxiang finally found that the speed of the number on the instrument had slowed down.

He was already at an altitude of 22,500 meters, and the thin air caused the plane to gradually stop climbing.

Because the sunlight could not be fully scattered, the sky above Fu Guoxiang's head at this time no longer appeared blue, but gradually turned dark black.

"Reach speed 2890, prepare to decelerate and descend in height."

If you choose to exchange speed for altitude, then you can probably rush to about 24,000 meters, but that is not today's test flight project anyway.

Moreover, due to the huge fuel consumption during afterburner flight, the fuel in the plane no longer supports him to continue to squander.

He has courage, but not brainless recklessness.

……

Everyone who had just stayed in the tower and was not in charge of directing the task had already arrived near the tarmac, and the accompanying photographers set up long guns and short guns aimed at the runway.

Ten minutes later, the slender figure of No. 04 gradually appeared from the sky, gradually descending to a height close to the runway.

Thanks to the new wing designed by Chang Haonan, the approach speed of the aircraft is much slower than the original, and it looks a little more calm.

The rear wheels are the first to touch the ground.

The rubber came into contact with the runway, sending up a puff of green smoke and a squeaky sound.

Then the parachute was released.

The plane finally came to a solid stop at the end of the runway.

The entire Beiling Airport was suddenly overwhelmed with cheers.

There is one more chapter in the afternoon, as usual

(End of chapter)