The aircraft had just been invented shortly after catching up with a major war. War greatly advanced the speed at which aircraft evolved. Soon there were differences in the types of reconnaissance aircraft, bombers, fighters, and transport aircraft. However, all the early aircraft were purely mechanized flying machines. The driver transmits motion commands to the aircraft through mechanical force transmission components such as the steering lever and foot pedals. These commands are then controlled by mechanical devices such as connecting rod gears, especially steel wires, etc., and the movement of the moving surface of the wing. to complete the change of the aircraft's heading speed and pitch turn, to achieve manned flight. And as the plane gets bigger and bigger, it flies faster and faster. The reaction force of relying solely on machinery and steel wire to transmit the pilot's maneuvering force is also increasing, resulting in more and more difficulty for the pilot to control the aircraft. So the hydraulic booster was invented. Partial reduction of the operator's burden on pilots. Since then, various instruments, radio stations and other devices have been installed on the aircraft. At this time, the aircraft is no longer a pure flying machine. Instead, there is a part of the electronic equipment on the plane. However, most of the electronic equipment at that time had little to do with the flight operation itself.
In the later stages of the second-generation fighter and the emergence of the third-generation fighter, the first fly-by-wire control system appeared. That is to say, the various action moments of the pilot's operation of the aircraft are not transmitted to the engine and various aerodynamic surfaces of the aircraft through the wire wire or including the hydraulic assistance system, but the actions operated by the pilot are first turned into electrical signals, and then the pilot's control is judged by the computer whether the pilot's control is reasonable. If it is reasonable, it is enforced, and if it is unreasonable, it is not executed. Generally speaking, 4 computers vote at the same time, and 3 of the 4 computers agree or 4 all agree to implement; 2 to 2 or 1 to 3, or even 0 to 4 will not be implemented. For example, for passenger and transport aircraft. The computer system on the plane is strictly forbidden for pilots to suddenly pull the rod above 40 degrees. Because it is easy to raise the nose too high, it will cause a stall crash. It can be said that the aircraft operation at this time and later. Already the onboard computer and the pilot are performing together. Superpower air forces were the first to use the 1553B bus. The flight control, weapon control and engine control of the fighter are all integrated, and the integrated control of the flying fire push is realized. Therefore, the fighter jet after three generations, which looks like an airplane, has actually become a flying intelligent robot.
As a result, electronic systems and software account for an increasing proportion of the cost of modern aircraft, especially advanced fighter jets. The cost of electronics and software in the third and a half generations is already as high as more than 60%, and after the fifth generation, it may account for 65% to 70% of the cost. Then for modern aircraft are "smart machines", software and hardware are equally important. Moreover, the operation software of modern aircraft is to integrate flight control, weapon fire control, and engine control into complete intelligence. Therefore, the more modern the fighter, the larger the scale of its software. For example, the F22A software is written in 8 years. By the time F35 included a certain 20, it would take more than 10 years. For overseas users who do not participate in the writing of software, it may not be successful to crack the source code of these aircraft in 50 years. Therefore, it is more important to have the entire source code of a certain fighter than to master part of the hardware of a certain aircraft. For example, the F35 has a lot of advanced subsystems, and the accessories are available in seven or eight countries. Including the irreplaceable critical component of the lift fan provided by Rolls-Royce. However, the source code of the F35 machine is still completely mastered by Loma. Other overseas users are not licensed with the source code of Loma. You can't hang a missile or a bomb.
Thus, including the source code of warplanes and missile systems, it has become the latest "remote control key" for weapons exporters to control overseas users. So what is the source code? The source code itself is not unusual. Any software, such as the Windows operating system of a personal computer, has its source code. Source code, also known as source programs, refers to uncompiled text files written in accordance with certain programming language specifications, which are a series of human-readable computer language instructions. To put it bluntly, source code is the most basic computer program. For advanced weapon systems such as warplanes and missiles, their source code is also constantly evolving. The source code of the early fighter flight control software was generally written in C+ language. Later, the ADA language was used more often. The ADA language is a high-level computer language suitable for the management and control of weapons systems. The overall requirements for programmers who write source code are quite high. Non-general level code farmers can operate. The source code for F35 is written in the ADA language, and a certain 20 is also considered to be basically the same.