Chapter 129 This Is the Real Interceptor! (2-in-1)

From the moment he got into the cabin, Fu Guoxiang was already looking forward to the high-altitude and high-speed test flight.

As a test pilot, he naturally read the aircraft's performance report during ground preparations.

The above shows that the performance of the new engine replaced by the No. 04 prototype is very obvious when the flight altitude is above 20,000 meters.

Not to mention anything else, the available thrust alone has increased from less than 4 tons to about 6 tons.

A full 50%!

Generally speaking, due to changes in factors such as air density, temperature, and oxygen content, the performance of aeroengines decreases as flight altitude increases.

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

Data such as sea level thrust can be used as a reference for aircraft engine performance, but it may not be of much value.

It is nothing new for two engines with similar thrust on paper to have twice the performance parameters after being installed and launched into the air.

The original turbojet 14 is obviously a model whose actual performance is not so optimistic.

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

But this "optimization" is relative.

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

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

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

Not to mention compared with monsters like the MiG-25 that have flown above Mach 3, even the F4 and MiG-23, which are not primarily tasked with interception, are stronger in this data.

What's more, due to the power response problem mentioned earlier, fast top speed does not mean fast acceleration. The original J-8's overall performance at high altitudes was still relatively clumsy.

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

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

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

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

Due to the unique geographical terrain in this direction, the Chinese Air Force has long been able to maintain a year-round presence at airports below 3,000 meters.

Although the plateau radar station with an altitude of 5,374 meters has a superior view and can capture the signal and issue an early warning almost as soon as the target takes off, in the face of the MiG-25R reconnaissance aircraft equipped by South Asian countries, the J-7 company taking off from Rongcheng or Licheng The range is not enough. Although the J-8I can pose a certain threat, when it slowly climbs and then accelerates to fly over, it often can only eat the exhaust of two R-15 engines...

This has led to the other party's harassment operations becoming more and more rampant over the past decade, and sometimes even deliberately provoking deep into the airspace.

One of Fu Guoxiang's comrades had an accident while trying to use power jump tactics to launch missiles beyond the maximum ceiling, and was eventually forced to leave the combat unit.

So today, after experiencing the surprises 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.

…

"Getting ready to start the supersonic flight test."

Fu Guoxiang repeated the command from the tower, and then followed his past habit of slowly pushing the throttle valve with his left hand and pulling the lever slightly with his right hand to allow the aircraft to enter a shallow climb.

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

Any movement of the throttle valve can be reflected in the change of engine thrust in a very short time.

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

This gave Fu Guoxiang great confidence.

If it is the previous No. 04 prototype, in order to ensure the stability of the engine's working condition, the process of the throttle valve from the middle thrust to the maximum thrust needs to be controlled within 20-30 seconds.

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

"The throttle has been pushed to maximum thrust."

Fu Guoxiang's voice sounded in the tower.

Only about 10 seconds passed before he was given the order to test the supersonic speed.

There was a burst of warm applause among the lay audience present, but it was immediately interrupted by the elder waving his hand.

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

The command room became quiet again.

"How's the condition of the engine?"

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

He was also a test pilot before he was grounded due to age. He once participated in the test flight of the J-8B model, so he is very familiar with the techniques of stable thrust and afterburner.

The time just now was too short.

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

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

"The power response of the aircraft is much more agile than before, and... the thrust at the current altitude is also stronger, and my speed increases very quickly!"

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

But on the one hand, the results obtained through calculations and simulations often do not match the actual situation.

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

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

However, while everyone was still digesting everything that had just happened, the No. 04 prototype had reached a new speed and altitude node.

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

That is to say, it has exceeded 1.5 times the speed of sound.

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

Therefore, under normal circumstances, the data will still be based on the pilot's report.

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

Fu Guoxiang in the cabin had left the sound far behind him. In front of his eyes, the number displayed on the speedometer had reached 2480, and was still increasing at a very fast rate.

This aircraft had reached similar speeds in past test flights, but at that time, it was already very difficult to continue accelerating.

"Altitude 20500, speed 2590."

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

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

In other words, the No. 04 prototype is far from reaching its limit.

"Request to continue the test flight!"

Fu Guoxiang finally experienced the performance of a real interceptor aircraft!

…

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

Although the No. 04 prototype cannot be regarded as its "first flight" this time, it has just been replaced with a new power system after all. It is actually responsible for the flight test of the turbojet 14 as a carrier platform.

Logically speaking, this first flight should not be too extreme a test.

Not to mention that there are leaders 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 are far from reaching the limit for this aircraft, and based on the previous high-altitude platform and aerial platform test results, there is indeed the potential for further attempts...

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

"First check the working conditions of the various systems of the aircraft at the current altitude and speed." Yang Fenghao stretched out a hand and pressed it on the back of the commander's seat:

"Especially to see if the engine can provide stable power supply, this is very important."

Fighters consume a large amount of electrical energy during flight and combat. Under normal circumstances, the IDG generator driven by the main engine generates electricity.

But the engine has its limits after all, and the total power it can provide is only so much. If the aircraft is allowed to fly close to its limit for a long time, or the engine is not stable, insufficient power supply may occur.

Later generations of F35 fighter jets have been troubled by this problem. They were unable to maintain the equipment on board and operate at full power at the same time. There was no news of a solution until Chang Haonan was reborn.

Therefore, if the power supply can still maintain normal, at least it means that the engine is still in a relatively comfortable working condition.

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

As a full-state prototype aircraft, the 1471G radar is naturally installed on the No. 04 aircraft.

Compared with the 208A monopulse radar on the J-8B, which is essentially a modified ranging radar, the performance of the 1471G is much better.

This is China's first X-band airborne pulse Doppler radar. It has (at least theoretically) downward-looking capabilities for the first time and can guide semi-active radar-guided missiles to conduct beyond-visual-range attacks.

No matter how you say it, for an aircraft like the J-8, it meets the needs.

However, as a price, the power consumed by turning on the radar is much higher than in the past.

"The radar is powered on and the self-test is successful."

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

After hearing the news, Chang Haonan and Yang Fenghao looked at each other with joy on their faces.

Compared with the aircraft body and aerodynamics that were completely designed and tested by them, the 1471 series of radars developed by the 14th Institute of Electrical Engineering is a factor that is not completely controllable.

But since the self-inspection can be completed at an altitude of more than 20,000 meters this time, it means that at least there is no problem fundamentally.

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

Strictly speaking, airborne weapons are not included in the August 3rd Project.

However, judging from the current situation, it is really possible to encounter an "organic and no bomb" situation.

Of course, these are all things for later. You have to eat your meals one bite at a time.

The missile problem cannot be solved by 601. The top priority is to continue to complete the test flight.

"The test flight is allowed to continue, but it must be ensured that the maximum speed does not exceed 2,900."

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

According to his simulation calculations of the performance of the J-8-3 after the engine change, it is no longer the power factor that limits the aircraft's maximum speed, but the airframe.

When an aircraft flies at supersonic speeds in a dense atmosphere, the friction with the high-speed airflow will cause the surface temperature of the aircraft body to rise sharply, which will lead to the weakening of the structural strength and stiffness of the body's material structure.

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

If you want to continue to make breakthroughs, you have to put a lot of effort into the body materials.

For example, the MiG-25 made extensive use of VNS-2 high-nickel martensitic steel and VNS-5 high-molybdenum and high-nitrogen austenitic steel, two aerospace-specific structural steels that were considered black technology at the time, in the body structure. Their material density is It is more than three times that of aluminum alloy, so it is almost equivalent to a T72 tank flying in the sky when fully fueled and loaded with ammunition.

The SR71, which is even faster, uses a large amount of aviation titanium alloy. At the same price, due to the ductility of the material, oil will continue to leak until the aircraft is "heated" to a normal state.

In short, even if the cost and technical difficulty are not considered, for an aircraft like the J8-3 that is oriented towards the 21st century, there is no need to pay a high price in order to break through 2.5 times the speed of sound.

When the plane's speed reached 2,800, Fu Guoxiang finally discovered that the numbers 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 no longer appeared blue, but gradually turned into dark black.

"Achieve speed 2890, prepare to slow down and descend altitude."

If you choose to exchange speed for altitude, you can probably reach 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 supported his continued squandering.

He has courage, but he is not reckless.

…

Everyone who had just stayed in the tower and was not responsible for command tasks had already arrived near the apron. The accompanying photographers set up long guns and short cannons and aimed them at the runway.

Ten minutes later, the slender figure of No. 04 gradually appeared from the horizon, gradually descending and approaching the runway.

Thanks to the new wing designed by Chang Haonan, the aircraft's approach speed is much slower than before, and it looks a bit more calm.

The rear wheel hits the ground first.

When the rubber came into contact with the runway, a burst of smoke rose up and a sharp "squeak" sound was made.

The parachute was then released.

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

The entire Beiling Airport was suddenly flooded with cheers.

There will be another chapter in the afternoon as usual