Chapter 646 The Amazing Flight Envelope
Song Shangcai was not a fool just now. After obtaining permission, he conducted a flight according to his own ideas that was not overloaded but could fully utilize all the control elements of the aircraft. action.
It only took about ten minutes to understand the operating characteristics of this aircraft.
Although it is not as perfect as the flight control, it is definitely no problem to conduct normal test flight subjects according to the plan before takeoff.
"Report to the command center and flight testing can begin."
The calm voice on the radio and the normal flight path on the radar made everyone here breathe a sigh of relief.
"Roger that!"
The commander sitting in front of the radar display simply answered with two words.
The test subjects of this flight had been memorized by the test pilot before takeoff, and the key route data of several core projects had been entered into the flight computer, so there was no need to do it every time as before. Every movement in flight requires confirmation from the ground.
Therefore, just as he was reporting the situation, Song Shangcai had already moved the throttle lever to a relatively low position and began to test the flight boundaries of the left engine bit by bit.
At an altitude of 6,000 meters, whether it is supersonic or subsonic, there is actually nothing easy to measure in level flight. The main thing is to see how much performance can be maintained under some practical working conditions.
So the plane quickly entered the subsequent test subjects under his deliberate control.
Soon, Song Shangcai in the cabin felt from the tachometer numbers that when the air intake state was damaged, the pointer on the left side was obviously more stable than the right side.
You know, AL31F is known for its high adaptability and tolerance, and this turbofan 10 even performs better in this regard...
Of course, step by step He still understood the truth. Data such as large sideslip angle and large angle of attack were naturally impossible to measure during the first flight.
For the first flight, the project is mainly shallow and comprehensive.
And judging from the current results, with the current status of this aircraft's single-engine turbofan 10, it is likely that the real limit cannot be measured——
The reason why the AL31F on the right should be retained , originally meant to be a guarantee.
In this way, if something happens to the test engine in the sky, it will not lose all power and electricity, and the aircraft can be brought back.
This is also a common practice in various countries when testing new engines.
However, judging from the status of this test flight, Song Shangcai is basically certain that the guaranteed engine limits the upper limit of this aircraft...
"We can only wait until both engines are replaced with new models... ”
He still felt a little pity in his heart.
"Report to the command center that the 6,000-meter altitude test has been completed and is ready to climb to the next test altitude."
It was still just a routine report, so while speaking, he was already following Pull the control stick to raise the nose of the aircraft and start climbing.
"Roger, pay attention to fuel consumption."
The tower's response came over the radio.
According to calculations, the light oil brought should be enough to complete the test subjects, but if everything can be calculated accurately, then there is no need for a test flight, so you still have to be careful where you should be careful in the sky.
Soon, the aircraft jumped to the second test altitude of 8,000 meters.
This time, Song Shangcai was obviously more familiar with the road. He completed the same subjects as in the 6000 meters in almost half the time compared to before.
Then of course there are 8,000 meters, 10,000 meters...
The theoretical maximum ceiling of the J-11 is around 23,000 meters, but the turbofan is in principle no better than the turbojet in a high-altitude environment, so the maximum limit of the second-generation aircraft The ceiling is basically achievable and has practical significance, while the maximum ceiling of the third-generation aircraft is relatively unrealistic, especially for the central lifting body type design.
So, according to the plan, this test flight will only proceed to the practical ceiling, which is 18,000 meters, and will be terminated.
However.
As mentioned above, if everything could be calculated accurately, there would be no need for test flights.
When Song Shangcai flew aircraft No. 1010 to an altitude of 16,000 meters, he discovered that the aircraft, which had become more and more comfortable in his hands, once again failed to obey orders...
And it was even worse than at the beginning. Much more serious.
Maintaining level flight is not stressful, but as long as you make a slightly larger movement, the aircraft will enter various strange postures.
Although it can be corrected later, this situation is obviously not suitable to continue...
So he immediately changed back to the original safe mode.
You even need to enter a password to disable safe mode, but you only need to press a key to switch back.
The aircraft's attitude quickly returned to normal.
Song Shangcai discovered that after restarting the integrated flight thrust control, the speed of the left engine suddenly dropped by nearly one-third from before...
In other words, at 16,000 meters At the altitude, the thrust of the turbofan 10 on the left is almost one-third higher than that of the other engine at the same throttle opening...
"Command Center, the 16,000-meter altitude envelope cannot be tested , The current judgment is that the thrust difference between the two engines is too big." After barely suppressing the shock in his heart, he took a deep breath and said on the radio.
During the test flight, no one can tell what will happen in the next second, so as long as the verification aircraft or prototype aircraft leaves the ground, it is the test pilot's greatest success.
Therefore, neither Chang Haonan nor He Ming can or will interfere with Song Shangcai's decision.
Not to mention the flight commander.
"Received, ready to return."
Although the original test subjects have not yet been carried out at two altitudes, as the first lift-off test of the new aircraft, it has obviously exceeded the task.
Furthermore, the failure to complete the two heights was not because the engine was not good, but because it was too powerful...
After a burst of cheers, a technician in charge of file paperwork quietly came together Go to Chang Haonan:
"Mr. Chang, how should I write this test flight log...?"
The latter was stunned and immediately understood what the other party meant.
In any case, this is considered an unexpected abort of a test flight.
Logically speaking, a problem has been discovered and a follow-up fault analysis meeting needs to be held.
But the situation this time... is obviously quite different from before.
“Just write it truthfully, but there is no need to be so rigid.”
After thinking for a while, Chang Haonan replied:
"Just state it after the situation and say that the reason for the suspension is that the performance of the test engine is too strong and it is difficult to maintain the balance of the verification machine."
There is quite a way of smashing a backboard in college and then saying that you can compensate, but The school must notify the criticism and publicize the déjà vu for one month.
The other party immediately understood, nodded, and stopped talking.
Although the test flight just now took a long time, it was actually hovering in the airspace around Shengjing and would not fly far, so it would actually be quick to return home.
Therefore, except for the necessary flight controllers, the rest quickly left the control center, preparing to greet the triumphant pilots as usual.
Luo Shida originally followed at the back, but when he saw He Ming not far away, he quickly stepped forward and came to the latter's side:
"I said Xiao He, this Comrade Haonan looks definitely old. Less than 40 years old, when this project is completed, he will probably become the youngest academician in our country, right?"
"Uh..."
The first half of this sentence is outrageous, But there was some reasonable judgment in the second half, and He Ming didn't know where to start for a while.
After a while he replied:
"Mr. Chang...I estimate that he will definitely be the youngest academician in our country."
"But now...he is only 25 years old. After completing the entire turbofan 10, he will definitely not exceed 30 years old. ..."
He originally wanted to say that it was possible to be an academician under the age of 40, but it was too outrageous to be an academician under the age of 30.
In the past two years, the things related to Chang Haonan were already outrageous, and this one was no exception, so he suppressed his firm words again.
Next to him, Luo Shida suddenly felt that something was not right——
Chang Haonan has been wearing old-fashioned work clothes these days, and he doesn't care much about trimming, so he always thinks that the other person is a young talent in his mid-thirties but with a young appearance.
It turns out that he is only twenty-five this year, and he is still considered a young genius...
That ten years ago, he was fifteen years old...
Obviously, his speculation just now seems to be true. Something went wrong.
"Comrade Haonan is twenty-five this year...so the current version of the turbofan 10 was originally...not his responsibility?"
Luo Shida asked with a strange expression.
He Ming shook his head directly:
"How is it possible? It was from the beginning."
Luo Shida was immediately shocked:
"Then he Wasn’t he just a kid when he first started taking charge of the project? ”
"Two and a half years ago...even if he was twenty-three, he wouldn't be considered a child, right?"
At this time, He Ming's attention was already on the plane in the distance that was constantly lowering its altitude, and he answered After finishing, he quickened his pace.
Luo Shida was left alone in the wind.
“It’s really only two and a half years...”
(End of this chapter)