The military-industrial scientific research system of the academic master.

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 20000 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 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 and Project ——

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 3000 meters.

Although the plateau radar station with an altitude of 5374 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 target's ground speed, 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 speed.

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.