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

Since the Turbojet 14 is not a new aircraft, and the previous ground simulation tests conducted in 624 have been very complete, the aerial platform at the flight test institute only needs to undertake a few test flight subjects such as mid-air restart and thrust transient. That’s it.

The testing process went smoothly and didn't last too long.

So a week after Chang Haonan returned to the 601 Institute, the installation test flight of the improved turbojet 14 engine was finally about to officially begin.

Because it was already late October and there were only two weeks left before the opening of the first Xiangzhou Air Show, so after discussing with Yang Fenghata and others, he jointly came up with a quite radical test flight plan——

Let two aircraft No. 03 and No. 04 conduct flight tests at the same time.

As a prototype that was not in full condition due to being rolled off the production line too early and had no time to be replaced with a new wing, the No. 03 aircraft will remain in Shengjing and will be mainly responsible for verifying the matching degree between the inlet and the engine, as well as the aerodynamics. Overall stability.

In fact, this is also the last "stumbling block" facing the August 3rd Project.

The real full-state prototype No. 04 will complete one basic flight test at Beiling Airport and then go directly to Yanliang to continue the test subjects including avionics and fire control systems as planned.

According to the original plan, these contents should have been completed gradually in the past month, but it was delayed due to the accident of the No. 01 prototype.

This solution can ensure the flight test progress, but it puts forward higher requirements for the final assembly efficiency of Factory 112.

"Lao He, the two engines supporting the No. 04 prototype have been shipped to you from the 410 Factory."

Yang Fenghao looked at He Ming sitting across the conference table and asked in a serious tone:

"Under the premise of ensuring quality, please tell me, when will the final assembly of prototype No. 04 be completed at the earliest?"

He Ming held his chin with one hand, lowered his head and thought for a few seconds:

"The minimum is two days, the maximum is three days."

This answer made Yang Fenghata and Chang Haonan look at each other, and they both saw surprise in each other's eyes.

Although the last time the latter went to Factory 112, the No. 04 prototype in the assembly shop was already in a state where only the engine was not in place, but two days still sounds a bit exaggerated.

The design of the J-8 aircraft is fundamentally derived from the J-7, so it naturally inherits many of the latter's problems.

For example, if you want to disassemble the engine, you almost need to remove the rear half of the fuselage first.

Of course, compared to the J-7, the J-8 at least makes the rear fuselage into a whole composed of several large parts, but in general it is still a rather complicated task.

Especially as a prototype machine, after each process is completed, there is a more complicated inspection process than that of a mass-produced machine.

"That's right. In the process of connecting with the comrades in the digital design team, we also refined some relatively advanced quality control methods."

He Ming saw the concerns of the two people opposite him, so he opened the notebook in front of him and began to explain:

"Although we were limited by hardware conditions during the final assembly of the prototype and were unable to upgrade to digital methods, we still referred to the five-station quality control model."

“The first station is responsible for cable laying and installation, the second station is responsible for pipeline installation and cleaning, the third station is responsible for finished product installation and electromechanical debugging, the fourth station is responsible for engine installation and hydraulic debugging, and the fifth station is responsible for flight control debugging and finished product handover. .”

“Separate quality thresholds are set after each station to strengthen the process control of the final assembly process. The zero rate of receiving problems between stations is 100%. Delivery to the next station is not allowed until the processing is completed, so as to ensure that product quality is controlled. "

"So after receiving the two engines, we only need to complete the work of four or five more stations. Two to three days is enough."

"In that case, let's make this decision..."

Just when Yang Fenghao was about to make the final decision, a rapid knock on the door suddenly interrupted everyone's discussion.

"Mr. Yang, there is an urgent call from the security department of the Central Office of the Communist Party of China."

Several people in the conference room looked at each other.

This is not a unit that you often come into contact with.

"I'll pick it up."

After Yang Fenghao finished speaking, he stood up and left the conference room.

……

Soon the day was set for the test flight.

Chang Haonan, Yang Fenghao and He Ming stood at the door of the factory, watching two slender and graceful aircraft slowly passing in front of them.

Due to the sudden phone call, the aircraft responsible for this test flight was temporarily changed to No. 04.

Compared with the No. 03 prototype that was simply equipped with a new engine, the No. 04 prototype that underwent in-depth modifications has much stronger performance in all aspects.

The test pilot sitting in the cabin is still Fu Guoxiang.

There were still a few empty seats on the aircraft tractor in front, but none of the three people sat on them. Instead, they followed the plane on both sides and walked step by step to the end of the runway of Beiling Airport.

The taxiing test was completed yesterday, and all they have to do today is test flight.

Test flight in full condition!

This is the third time Fu Guoxiang has performed the "first flight" of this aircraft.

But this time the situation is a little different.

On the one hand, it is the test flight subjects he needs to complete, on the other hand...

Fu Guoxiang closed the cockpit cover and glanced at the tower not far from him.

A special leader will come to watch today.

"No. 04, prepare to take off."

He gathered his thoughts and focused on the dashboard in front of him.

"No. 04, permission to take off!"

A slightly unfamiliar voice came from the radio, speaking slower and with a slight Jianghuai accent.

The takeoff process has almost become instinctive for a senior test pilot like Fu Guoxiang.

Start the engine, push the lever, wait for the speed to stabilize and then release the brake.

But this time, he had already formed muscle memory and found that the tachometers of the two engines had stabilized at about 3/4 long before he released the brakes according to his past habit.

Obviously, the stability of the engine has been significantly improved compared to before.

What happened after releasing the brakes confirmed his suspicion.

If the last test flight showed that the aircraft was only "light" at low speeds, then this time Fu Guoxiang really felt "powerful".

To use a driving analogy, in the past, after the J-8-3 stepped on the accelerator, the gearbox had to react for two to three seconds before downshifting at a very slow speed.

After installing a new engine, once the accelerator is stepped on, the entire vehicle will quickly complete downshifting, fueling and acceleration operations in one go.

Therefore, although the total thrust of the two engines on paper has only increased by more than 1 ton, the response speed of the power has undergone earth-shaking changes.

Several routine low-altitude and low-speed test subjects were quickly completed, and Fu Guoxiang finally received a request for a supersonic flight test on the radio.