Because of this, Huaxia exchanged a number of J-6s for a MiG-21MF fighter from Egypt three years ago. Pen Fun Pavilion wWw. ｂiquge。 ｉｎfo

The MiG-21MF is the latest modification of the MiG-21 series, and its performance has been greatly improved compared with the earlier MiG-21, and it is widely equipped with the air forces of the Soviet Union, Eastern Europe, India and other countries.

The J-7III project is based on the MiG-21MF, with the aim of changing the shortcomings of the J-7 series such as short range, short radar range, and weak firepower.

It is a pity that the J-7III made in China cannot be said to be a successful work.

There are many reasons for this.

First of all, the maneuverability of the J-7III has decreased significantly compared to that of the J-7II.

Due to the increased weight of the airframe and the limited increase in engine thrust, the counterweight required to maintain the changed balance of the airframe alone amounted to 100 kg, as in the case of the MiG-21MF.

The enlargement of the shock cone leads to insufficient air intake during combat, which seriously affects maneuverability, and the diameter of the fuselage increases, which also increases drag.

Secondly, although the JL-7 radar detection range equipped with the J-7III reaches 26~28 kilometers, this value does not bring fundamental improvement to the operation, and it still depends on ground radar guidance.

What is even more fatal is that the above-mentioned model was successfully developed too late and no longer meets the needs of the operation at that time.

After the J-7III was put into trial in the troops, the troops generally opposed the equipment of this model.

This is also one of the reasons why our army did not massively adopt Type III.

As the chief designer and deputy chief designer of the J-7III project, Lu Yang and Chen Liangwei naturally do not know what the future fate of the J-7III project will be, and at this time, they are still worried about how to speed up the progress of the J-7III project.

"The Jinling Institute of Electronic Technology has completed the research and development of the KJ-11 autopilot and the ADS-1 air data computer, and the JL-7 single-pulse fire control radar and the AI-8D (HK-03D) optical shooting sight are also progressing relatively smoothly, and should be able to catch up with the first flight node at the end of next year. ”

"I'm not too worried about the piece you are responsible for, the key now is this improvement, the new parts account for almost 80%, the new materials account for 37 items, all parts have to be re-drawn and trial-produced, and all structural drawings and system drawings must be issued at the end of the year, according to the current progress, it is too late. ”

"There are already more than 50 people in the institute who have been involved in the project team, and even the college students who have just joined our unit this year have not let go. ”

"It's really not good, and I can only work overtime and increase the workload. Now there is less than a year and a half before the first flight node, and all structural drawings and system drawings must be issued within three months......"

……

Yang Weining listened to Lu Yang and Chen Liangwei discuss for a long time before he figured out the dilemma faced by the J-7III project.

According to the original plan of the Air Force, the J-7III should complete its first flight in 1980, finalize it in 1981, and reach an annual production of 1,000 aircraft by 1982.

However, when the trial production actually began, the first flight was delayed for various reasons, the biggest of which was the controversy over the reference design and the survey design.

It should be noted here that the so-called reference design is to replace the old parts of China's more advanced components on the basis of the reference machine and its shortcomings.

For example, in the design of the J-8, China used the wreckage of the American F-4 to learn a lot of things that the Soviet Union did not have, and its design concept and effect are much more scientific and reasonable than some Soviet-style designs.

For example, the manufacturing technology of rubber thin-walled soft fuel tanks with a thickness of only one millimeter, the use of fluoroplastic conduits in the internal pipelines, etc., were all technologies that the Soviet Union had not mastered at that time, and the J-8 had been used very maturely when it was designed.

The surveying and mapping design is completely based on the design and process of the MiG-21MF, without any improvement.

Comparatively speaking, the progress of the survey design is much faster than that of the reference design.

In this era, the Soviet Union was in its heyday, and once a war broke out, strategic bombers such as Tu-22 and Tu-95 could penetrate into China at any time, and China was facing great air defense pressure, and the military urgently needed an all-weather fighter.

Because of this, the top management was torn between reference design and survey design, which directly led to the project being delayed for two years.

It was not until the end of 1981 that the top leadership's judgment on the international situation (there was no major war in 30 years) was closed, and the controversy over the survey design and reference design was settled, and the reference design was finally victorious.

As a result, Lu Yang and Chen Liangwei served as the chief engineer and deputy chief designer of the J-7III project respectively, and Chen Liangwei served as the chief designer of the avionics and flight control subsystems at the same time.

In this way, the pressure on the two of them is great.

According to the plan, the J-7III project team must complete the overall design in December 1981, issue theoretical drawings, send all structural drawings and system drawings at the end of 1982, complete the first flight in October 1983, and finalize the design in December 1984.

The project team led by Lu Yang and Chen Liangwei had to work overtime, but even so, more than half a year later, less than 30 percent of the structural drawings and system drawings of the J-7III were completed.

If this continues, it will definitely not be possible to complete the originally planned tasks by the end of the year.

Lu Yang and Chen Liangwei can be described as under great pressure.

Yang Weining saw Lu Yang and Chen Liangwei's sad looks, and couldn't help but say: "Uncle Lu, are our current parts mechanical drawings all hand-drawn?"

Lu Yang said a little bitterly: "You don't need to draw by hand, so what kind of mapping can be used? Why, you didn't learn this in college?"

Yang Weining shook his head and said with a smile: "Mechanical drawing is a basic course in the freshman year, how could I not have studied it? By the way, Uncle Lu, our unit has a large computer, right?"

Lu Yang frowned and said, "Why are you asking this?"

Chen Liangwei seemed to see Yang Weining's thoughts, and said: "The computer must have it, Xiao Yang, if you have any ideas, you can say it directly." ”

Yang Weining showed a smile on his face and said, "I think I may have a way to speed up the process of drawing structural drawings and system drawings." ”

"Do you have a way?"

"What's the solution?"

Lu Yang and Chen Liangwei looked at each other, and some didn't believe that Yang Weining, a young man who had just graduated from college, could solve problems that no one in the whole institute could solve.

Yang Weining smiled: "Uncle Lu, Uncle Yang, I don't know if you have heard of CAD technology?"

“CAD？”