Chapter 294

1981, December 12.

Capital, Aviation Industry System, conference room.

"Leaders, our Institute 601's third-generation fighter project is still the earlier J-13, but it has undergone a major upgrade; for example, Ha Gong Da will help us solve the problem of onboard avionics equipment, so we will also install an advanced pulse-Doppler radar on this aircraft, giving it medium-range interception capability."

Liu Jianshe of Institute 601 stood on the stage and introduced to everyone.

"In terms of engines, we will also rely on the M53 measurement and imitation task supported by Ha Gong Da; currently, this engine has been officially given the designation Turbofan Ten by the Air Force. Although it has a single-rotor structure, its high-altitude, high-speed performance is top-notch. We believe this will allow our J-13 fighter to better accomplish air defense interception missions..."

On the presidium, Lao Lin looked at the person beside him.

"San Shui, what do you think of this aircraft?"

"Lao Lin... I'm not with the Air Force, nor with the Aviation Industry System, I... I'm not in a position to comment."

"That's why I'm letting you speak now; later, I'll repeat your words."

"Well then, I have many questions about this aircraft..."

One hour, two hours, three hours......

Liu Jianshe talked for a full three hours; seeing this continue, the entire morning had completely passed.

"Cough cough, let me interrupt." Lao Lin said: "You just introduced a lot, but I found that many things I wanted to hear were not mentioned; may I ask a few questions now?"

"Lao Lin, please go ahead."

"First, does this aircraft use fly-by-wire?"

"Well, we think there is currently no fly-by-wire aircraft domestically; for now, hydraulic operation is the most mature and reliable, we cannot risk trying these new technologies; the step is too big, it's easy to... cough cough."

The earliest aircraft used cable control; the pilot's control stick was connected to cables, which drove the tail surfaces. As the aircraft grew larger, the force needed on the cables increased, to the point where even a weightlifting champion might not be able to manage it.

Thus, during World War II, aircraft began using hydraulic drive; the control stick connected to a hydraulic cylinder, where the hydraulic fluid under pressure made moving the control surfaces much easier.

To this day, many aircraft still use hydraulic drive, for example, the MiG-29 recently put into service by the Russians.

However, looking at the Western world, fly-by-wire is already the most common method; the pilot's control stick connects to a sensor, transmitting an electrical signal via a data bus to an electric actuator, which then drives the control surfaces.

The Russians first used fly-by-wire on the Su-27, but because their electronic technology was poor, they still used an analog system, whereas the West had already transitioned to the digital era.

At the same time, aircraft operation must absolutely not fail; this fly-by-wire system also cannot have only a single loop.

At a minimum, there must be three loops; thus, if one loop fails, the other two remain normal, and following the principle of minority subordinate to majority, the aircraft's operation will still follow the pilot's input—this is triple-redundant digital fly-by-wire.

To further improve reliability, allowing for a second error, that is quadruple-redundant digital fly-by-wire.

The East lacks this technology; using it rashly would be too risky.

"Since they use hydraulic control, they certainly don't have a statically unstable design, do they?"

When the pilot releases the control stick and the aircraft can automatically return to equilibrium, that is a static-stable layout; such flight is very safe, but it also means the aircraft lacks agility.

Advanced third-generation fighters are all statically unstable designs; a slight movement of the control stick causes the jet to change attitude dramatically, giving high maneuverability, but aircraft control becomes very difficult; without fly-by-wire control, it cannot be controlled at all.

"Yes."

"In other words, although this aircraft looks like an F-16 on the outside, it's actually just a second-generation airframe with a superficial makeover, lacking any third-generation characteristics, right?"

What is a third-generation fighter? It's not about outward appearance, but substance!

Fly-by-wire, static instability, leading-edge extensions, wing-body blending... having these technologies makes a true third-generation fighter!

Initially, in the U. S. lightweight third-generation fighter competition, the YF-16 and YF-17 won first, while the losing projects, such as Lockheed's X-27 and Ford's V-, were merely second-generation airframes with minor improvements, entered as third-generation fighters, and were eliminated in the first round!

Lao Lin looked at Liu Jianshe: "Engineer Liu, in the future we will face opponents like the MiG-29 and Su-27, and possibly later the F-16 and Mirage 2000; do you think our J-13 can contend with these opponents?"

The conference room fell into silence.

It was obvious the Air Force was dissatisfied with the J-13!

"I think we'll wrap up the morning meeting here; you all should think carefully about how we can make our Air Force win future wars."

The meeting adjourned, and the people from Institute 601 were dumbfounded.

"What MiG-29, F-16—these aircraft's performance is naturally advanced, but... this is completely beyond our current industrial base."

"Exactly; we have absolutely no foundation for fly-by-wire at all!"

"Everyone, I heard that Ha Gong Da is researching..."

Everyone was shocked: "Ha Gong Da still has fly-by-wire technology? If that's the case... let's go find Qin Miao now!"

After lunch, he could rest a bit, but Qin Miao had just lain down on a makeshift bed made of three chairs when he was awakened by noise.

"Comrade Qin Miao, is Ha Gong Da developing a fly-by-wire system?"

Qin Miao rubbed his eyes, sat up, saw Gu Lao's expectant gaze, and nodded: "Yes!"

"Can it be matched with our J-13?"

"We can provide the hardware, but the hardest part of fly-by-wire control is writing the flight control laws; this depends on the designer's mastery of the aerodynamic shape. As far as I know, the giants of military aircraft development worldwide have crashed planes due to software bugs; you..."

"No diamond drill, no porcelain work!"

"Even if we install fly-by-wire, we still need top-notch software! An unstable layout is like an untamed wild horse; a slight flaw in the program will make it impossible to tame!"

"Comrade Qin Miao, can Ha Gong Da help us write the flight control program? We can provide R&D funding..."

"No." Qin Miao refused on the spot: "Flight control is the core of an aircraft; if you outsource even that, what are you developing aircraft for?"

"Well, I heard that the parts from that F-16 have all been obtained; does it possibly contain the F-16's flight program?"

Qin Miao's eyelids twitched wildly; you really...

"No, certainly not! Now we need to develop a third-generation fighter, not copy! Even if the aerodynamic shape is slightly modified, the flight control program must change accordingly; direct copying... that would be a crime!"