As the test flight and transportation site of Shengfei Group, the scale of Beiling Airport is not large, after all, there is no daily take-off and landing pressure here.

As a result, within a few minutes, No. 1401 was at the end of the take-off runway, and its wings were readjusted to a more take-off 20° sweep angle.

"The area has been cleared, and the 1401 can take off."

Fu Guoxiang put on an oxygen mask, slowly pushed the throttle valve while maintaining the braking state, and watched as the pointer of the engine tachometer, which had been replaced by a Huaxia style, slowly turned to the right.

As a test pilot stationed at Field 112, this was his first exposure to the turbofan 9A.

In fact, at present, there are only three aircraft in the whole of China - the 01 and 02 prototypes of the J-7A, and the 1401 aircraft using the turbofan 9A.

However, the steady increase in revs still brings a lot of confidence.

It even reminded him of the situation of the J-8C after the test flight overhaul two years ago.

It is also the first two engines to be installed, and it is also such a stable speed.

After the engine reached take-off thrust and stabilized for a few seconds, Fu Guoxiang released the brakes, and the plane began to accelerate on the runway with a roar.

The feeling of pushing his back from behind him made Fu Guoxiang himself a little surprised.

In his opinion, such an aircraft with an empty weight of about 17.5 tons even after weight reduction seems to be relatively clumsy.

Compared with the J-11 he had flown before, the F14's greater weight and drag make the acceleration ability of this model not optimistic, which is a little delayed, but the excellent lift coefficient still allows this aircraft to reach take-off conditions at a distance of about one-tenth of the runway, that is, about 350 meters.

After all, the F14 is a relatively mature design, and the modified "first flight" is not exactly the same as the real first flight after all, and it is much more open in the setting of flight subjects.

After pulling up the plane, Fu Guoxiang put away the landing gear, then let the plane accumulate some speed a little, and then did a personal habitual large-angle climb action.

Almost as soon as the throttle valve was pushed to the bottom, the two engines spewed a pale blue tail flame with Mach rings downwards in mid-air, and the wings were adjusted to a 68° sweep angle with lower drag and better suitability for acceleration in less than seven seconds.

The two new engines with a lot of power at low altitude and low speed provide Fu Guoxiang with a fairly confident ability to climb, at least in his senses, the current climb process is close to 70 degrees, and there is almost no loss of speed.

Increasing the sweep angle significantly reduces the lift coefficient provided by the wing, but ......

Miracles are made vigorously.

On the other hand, this slightly wild action also set off a wave of exclamations in the command center of the tower.

From representatives of the Persian Air Force, of course.

Since there has been no formal means of importing spare parts for more than 20 years, in order to save the life of the body, they have rarely carried out such "wild" driving.

And, on the other hand, if the TF30 engine in the past dared to perform such a large-scale violent maneuver at low altitude, eighty percent would have entered a state of surge......

"The rate of climb this time is visibly higher than in the past......

A colonel standing next to the Persian general at the head stared for a moment, then estimated.

"Of course."

He Ming already had a basic idea of the performance of this aircraft, so he did not pay attention to the aircraft outside, and immediately explained after hearing the evaluation of the Persians:

"We have replaced the skin parts that do not involve the main load-bearing structure, which has reduced the empty weight by about 700kg, and the sea level thrust of the turbofan 9A engine has been increased by more than 17% compared to the past."

"In this way, the thrust-to-weight ratio of the whole aircraft can be increased by almost one-fifth during take-off, and the power performance is naturally completely different."

When he said this, He Ming even had a feeling of confusion-

The principle of Lida Brick Flying can be said from his mouth one day.

It's magical.

"Also."

He Ming's tone suddenly had a little suffocated laughter:

"I can assure you that the plane was refueled with a standard amount of fuel before the test flight, and there was absolutely no case of turning on the engine in advance to consume fuel, thereby reducing the take-off weight."

Hearing this, even the Persian general laughed directly:

"Well, we've been staring at it just now, and you guys really didn't play tricks on that......"

The two were talking about the events when Persia purchased US fighter jets.

At that time, the candidates were Grumman's F14 and McDonnell Douglas' F15.

Originally, the flight performance of the latter should be much better, but Grumman specially let McDonnell Douglas perform first, and his F14 kept the engine on the ground to consume fuel, thus making up for the disadvantage in thrust-to-weight ratio to a certain extent.

Although the authenticity of the story is no longer verifiable, the story has become one of the famous urban legends in the field of international arms sales.

After a short joke, He Ming quickly returned to the topic:

"To get back to business, in addition to the predominance of thrust at sea level, we have adopted active control technology for blade split flow in the design of the turbofan 9A engine, which can cope with very extreme intake distortion."

"Although the specific flight envelope data still needs to wait for our test pilots to fly the results, from a qualitative point of view, the improved F14 can allow pilots to perform unimaginable violent maneuvers in the past, such as ...... You've seen it anyway. ”

The F14A purchased by Persia is a technical version of an earlier batch, and the engine's sea-level afterburner thrust is only 8530kgf, while the turbofan 9A after some turbofan 10 technical improvements, this figure is above 10000kgf.

"If you look at it this way, the improved F14IC model can probably be equivalent to the level of the U.S. military F14D?"

Obviously, the Persian Air Force has always been concerned about the improvement of the Tomcats on the US side.

"So to speak."

He Ming nodded after a little hesitation:

"Although the sea-level thrust of the turbofan 9A is smaller than F110GE400 that of the F14D, the overall improvement ideas and the performance orientation of the improved model are similar."

Speaking of which, he suddenly remembered an interesting thing:

"Speaking of which, the total pressure ratio of the F110GE400 and turbofan 9A engines is exactly 30.7, which is 50% higher than that of the TF30 engine."

"Of course, as a price, the F14 after the reissue, whether it is our F14IC or the U.S. military's F14D, the high-speed performance and maximum flight speed have actually decreased."

"Oh?"

The Persian general, who had been holding a telescope, was also attracted to this topic about engines:

"You designed it with the F110 in mind?"

In fact, the reason why they decided to hand over the F14 to Huaxia for transformation is that half of them fancy the size, weight and performance of the 1493 radar can perfectly replace AWG9, and the other half is that when they visited the Pickaxe Fei Group, they found that the performance of the turbofan 9A engine was quite good.

"Not really."

He Ming shook his head:

"This is a complete coincidence, in fact, the turbofan 9A is a by-product made by one of our chief designer comrades in order to do technical verification, and it is impossible to bother to benchmark other models in this place of total pressure ratio."

This answer was originally just his truth, and there was no deep meaning to speak of, but the effect was surprisingly good.

"Wait, you mean, by-product...... Already has such good performance? ”

Now that the 1401 had flown away, it was impossible to see it even with a telescope, so the Persian general simply put it aside and asked with a shocked look on his face.

He Mingxin on the other side said that you don't know what Mr. Chang is preparing to do on the turbofan 10, but the content of the third-generation (actually 3.75 generation) turbofan engine is confidential, so he had to change a more traditional answer:

"Although it is a by-product, the technology used in it is the latest technology from the 90s and even for the next century."

"It can be said that although the turbofan 9A was born from the British's Spey, it has no direct relationship with Spey now......"

(End of chapter)