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 performance report of the aircraft when making 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 more than 20,000 meters.
If nothing else, the available thrust alone has increased from less than 4 tons to about 6 tons.
Fully 50%!
Generally speaking, due to changes in factors such as air density, temperature, and oxygen content, the performance of aeroengines will decrease 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 they are 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 that 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 altitude 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 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 Rongcheng Military Region for a long time and flew both the J-6 and J-8I models.
Due to the particularity of the 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, 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 eventually 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.
“Prepare to start 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 response of the tachometer needle was still the same as when it was on the ground.
Any movement of the throttle valve can be reflected in the change of the engine thrust in a very short time.
And it can be seen from the instrument status that even at the moment when the afterburner starts to work, 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 valve has been pushed to the maximum thrust state.”
Fu Guoxiang's voice sounded in the tower.
Only about 10 seconds passed before he was given the order to conduct the supersonic test.
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 is 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 used 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 steady voice continued to be heard, 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.
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 difficult to quantify on paper.
Hence, what the test pilot reported was definitely beyond most people's expectations.
However, while everyone is still digesting everything that has just happened, the No. 04 prototype has reached a new speed and height 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 process, ground radar can only give the ground speed of the target, and the more valuable data for an aircraft is the airspeed.
So 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 has reached similar speeds in past test flights, but at that time, it was already very difficult to continue accelerating.
“Altitude 20500, surface speed 2590.”
This is 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 prototype No. 04 cannot be regarded as a serious "first flight" this time, it has just been replaced with a new power system. 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 should be 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 confusion, he turned back and looked at Yang Fenghao and Chang Haonan who were waiting behind him.
“First check the working conditions of 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 the 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 solution until Chang Haonan was reborn.
So, if the power supply can still be maintained normally, it at least 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 to the 208A monopulse radar on the J-8B, which is essentially a range-finding radar modified, 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 over-the-horizon 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.”
When the radar is turned on at an altitude of 20,000 meters, if a target drone 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 there is no problem with the power supply.
Chang Haonan and Yang Fenghao looked at each other and looked happy after hearing the news.
Compared to the aircraft body and aerodynamics, which were designed and tested entirely by their own hands, 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 霹雳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 things for later, you have to eat your food one bite at a time.
The problem of missiles cannot be solved by 601. The top priority is to continue to complete test flights.
“The test flight is allowed to continue, but the maximum speed must not exceed 2900.”
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 of the body's material structure and a reduction in stiffness.
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 safe flight.
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 cost, due to the ductility of the material, oil will 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 2800, Fu Guoxiang finally discovered that the numbers on the instrument were rotating slower.
He was already at an altitude of 22,500 meters, and the thin air caused the plane to gradually stop climbing.
Since the sunlight cannot be fully scattered, the sky above Fu Guoxiang no longer appears blue, but gradually turns 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 Unit 04 gradually appeared from the horizon, gradually descending and approaching the runway.
Thanks to the new wing designed by Chang Haonan, the approach speed of the aircraft is much slower than before, and it looks more stable.
The rear wheel touches the ground first.
When the rubber came into contact with the runway, a puff of smoke rose up and a sharp "squeaking" sound was made.
The parachute was then deployed.
The plane finally stopped steadily at the end of the runway.
The entire Beiling Airport was suddenly drowned in cheers.
As usual, there will be another chapter in the afternoon
(End of this chapter)
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