At the 14th Zhuhai Air Show not long ago, a number of Chinese fighter jets represented by J-20 appeared one after another. Their stunning appearance and excellent flight performance attracted countless fans at the air show.
The opening of this air show also made people truly realize that Chinese fighter jets are in a period of rising, and countless top models will inevitably appear in the future.
However, with the increase in the attention of fighter jets in the new era, many people suddenly noticed that although a fighter jet has condensed the highest level of military industry, its service time is often only more than ten years, and it is even worse than the service life of some family cars. What is the reason? Considerations for the development of
technology
First of all, we must understand that the formal service of fighter is an extremely difficult process, and it requires calling for a huge initial team including military consultants, designers, and veteran fighter pilots.
even needs to hire foreigners or consultants with combat experience to participate in certain special issues. This means that the initial team convening will take a lot of time and cannot be completed in just a few weeks.
Moreover, after the initial team completes the convening, it will take a lot of time to discuss, especially the positioning, performance and cost of the fighter. The entire team needs to discuss for months or even years. After
, after the original plan is determined, it needs to be reported layer by layer and handed over to various departments for approval, which will take a certain amount of time here.
If the initial design plan is not approved, it will involve rediscussion and design, which will inevitably consume a lot of time.
In addition, even if the plan can be approved at one time, the procurement of parts and the installation of production lines will require a huge amount of time.
It is worth mentioning that this must be based on my country's terrifying infrastructure capabilities. After all, whether it is the construction of factories or the construction of workers' dormitories, these essentially require strong infrastructure capabilities to ensure.
Finally, when everything is ready, the factory needs to carry out the first batch of production. In this process, engineers also need to spend time debugging the equipment, verify the factory parts, and participate in the assembly process.
If everything goes well, the new fighter can land, but at this moment, the new fighter is still in a long test period until it is in service.
It should be noted that accurate judgment cannot be made during the test period, because as soon as some fighter jets are launched, countless problems will be exposed, which may involve returning to the factory or redesign.
Therefore, the duration of a fighter from design to final service often exceeds ten years. What's more, such as India's glorious fighter, its research and development time once reached 30 years.
This long "implementation" process will lead to new problems, that is, there may be a mismatch between the design of fighter jets and the times.
To give a simple example, the design of a fighter jet may have been a cross-age model ten years ago, but after ten years of implementation, its technology may have become extremely ordinary, or even worth mentioning.
Therefore, as far as modern fighter jets are concerned, most of them will welcome new successors after several years of service, thus setting an alarm clock for their retirement.
material and engine shackles
In addition, fighter jets, as a carrier that undertakes high-strength flight, also consumes a great amount of material, which makes most fighter jets, even if they are not attacked, will change the strength of their materials when they reach a certain age.
Especially under the action of long-term cyclic force, the fighter is likely to experience metal fatigue , that is, permanent damage to the metal, and the degree of damage will continue to accumulate until a certain flight is subjected to force again, it will suddenly collapse, causing irreparable losses.
For example, the US Air Force's F15 fighter jet had a "dead head" due to metal fatigue, that is, the nose suddenly broke. Fortunately, the pilot responded in time, so it completed the parachuting self-rescue. From this, it is not difficult for us to see the importance of the life of the fighter jet material.
In addition, after removing the material limitations, the service life of the fighter engine is also a major constraint on the service of fighter jets.
According to the definition of engine life in the aircraft manufacturing industry, the life of a normal fighter engine generally needs to be higher than 3,000 hours. If converted into a specific time, it is about 125 days.
This sounds a bit short, but it is real data. However, it should be noted that these thousands of hours represent only flight time, not including the time limit of the fighter jets on land.
Simply put, it is only when the fighter starts to take off the engine and starts to calculate this time. According to relevant statistics from Europe and the United States, the annual flight time of a service fighter is generally in the range of 200 to 300 hours.
This means that the engine life of 3000 hours refers to the ten-year service life of the fighter.
Of course, the engine life of 3,000 hours can only be regarded as the threshold for the fifth-generation fighter to a certain extent. For example, the WS series engine used by my country's J-20 has a service life of 4,500 hours.
For example, the AL series engine used by the Russian Su57 has a higher service life, reaching 5,000 hours.
As for the longest-lasting fighter engine, it is the F119 engine equipped with the US F22. Its life span exceeded 8,000 hours, and it can be said to be the most "longest-lived" existence in the fifth-generation fighter .
expensive
However, the service life of F22 is not innate, it requires some "life-extending" operations.
In a simple way, if F22 wants to achieve a flight life of 8,000 hours, later maintenance and maintenance are essential. Moreover, this kind of maintenance is not conventional maintenance, but requires reinforcement of accessories, or even replacement of accessories.
This set of operations sounds very simple, but the specific implementation is difficult to achieve. First of all, the adaptation of parts will become a problem. Modern fighter jets can be understood as an electronics overall, and each part needs to be compatible with the switchboard.
However, the assembly of new parts will often cause power differences between new and old parts, which will affect the overall performance. If you want to completely solve this problem, you need to replace parts on a large scale. The production cost of
fighter parts is simply astronomical, and even the United States itself is difficult to support this maintenance expense, so that the US military will retire a batch of F22 fighter in 2023. The fundamental reason is that the maintenance cost is too high.
Of course, the United States is already lucky. At least the production line is in its own hands. If you want to maintain it, you only need to consider the funding issue. But for countries without the original fighter production line, the problem is obviously more complicated.
Let’s take Japan as an example. The country once imported F15 fighter jets in large quantities from the United States, but with the increase in service life, the life limit of these fighter jets has gradually come.
Unlike the United States, which is rich and powerful, Japan seems extremely hesitant about the retirement of the F15 fighter jets. In the end, in order to save procurement costs and to own their own fighter jets, they developed F15j and F15DJ fighters based on the F15 fighter jets. The two models of
are called the embodiment of Japanese technology. However, even so, the failure rate of the two fighter jets remains high, especially the F15DJ, and even parts have been dropped during flight, which is actually a manifestation of maintenance difficulties.
From this point of view, whether modern fighters consider the advanced technology, the service life of materials and engines, or weigh the cost of later maintenance, they all point to one point, that is, the service life of modern fighters cannot be too long.
Otherwise, the disconnection of technology and the infinite surge in costs will make fighters fall into infinite embarrassment. Just as the aforementioned Indian glorious fighter jets are now facing the situation of "eliminating when leaving the factory", which is just a laughing stock.
Reference:
"5000 hours vs. 14000 hours, why is the lifespan of China's aviation engine shorter than that of Western countries? 》-------- Phoenix.com
"The lifespan of a fighter is 3,000 hours, but why can it serve for decades? Here's the reason"--------- Sina.com
"Why the service life of a fighter engine is so short? 》--------- Zhihu
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-