In 1978, I was admitted to Harbin Institute of Technology

Chapter 295 The first test pilot of Master Shi, a genius who has flown 22 types of aircraft in 23 years, can't afford to have any problems!
This problem doesn't seem that difficult to understand.

It's just that we don't see these big shots in China as often anymore.

Even though the improved PL-4 did not encounter this problem, the J-7 still had this problem after the introduction and test firing of the Python-3: the missile engine thrust was greater than the fighter jet engine thrust, which caused the fighter jet to deflect after the missile was launched. During the pilot's trim process, the fighter jet's air intake also inhaled a large amount of the exhaust gas from the missile just after launch, which caused the engine to shut down!
"Let's go to the technical discussion room."

Xie Wei knew that it would be difficult for everyone to understand just by talking.

Upon arriving at the technical discussion room at the test firing range, Xie Wei made no attempt to be polite. He walked to the blackboard, picked up a piece of chalk, and drew a simplified diagram of the J-7 on the blackboard, also marking the positions of the air-to-air missiles.

"This is a diagram of a J-7 carrying a PL-4 air-to-air missile in the air. When launching the missile, the direction of the force acting on the aircraft is like this..."

Xie Wei drew a simplified diagram of the forces acting on a fighter jet when it launches a missile, and made thorough annotations.

Mechanics is a fundamental course for aerospace-related majors. If you don't even know the basic force structure of an aircraft during flight, what's the point of designing an aircraft?

Only the test pilots present had relatively little professional knowledge in this area.

However, because of their long-term contact and the detailed drawings by Xie Wei, he immediately understood the meaning just by looking at the force diagram on the blackboard showing the fighter jet launching a missile.

"The thrust of a fighter jet's engine must maintain the aircraft's balance in the air. Missiles are launched directly from the pylon. At this time, the instantaneous thrust generated by the missile engine is applied to the fighter jet in a balanced flight state. If the thrust margin provided by the fighter jet's engine is less than the thrust at the time of missile launch, a diagonal torque is generated, which causes the fighter jet's flight direction to deflect..."

A force diagram is easy to draw and understand.

There's no need for further explanation.

"But the problem now is that the engine has stalled!"

"That's what one of the pilots said."

If the aircraft only deflects when launching a missile, the pilot can simply adjust the flight attitude using manual controls.

The key problem is that the engine stalled!
If the engine cannot be restarted after it is shut down, the only result will be a crash!
Even experienced test pilots are prone to problems, let alone air force pilots who may not even fly for an hour a week.

If several crashes occur, not only will the Air Force despise the J-7 even more, which it already dislikes, but it will also be detrimental to national defense.

"After the balance is achieved, the fighter jet's flight direction is the same as the missile's flight direction, which means it is actually following behind the missile... However, the air-to-air missiles launched at the beginning do not burn their solid fuel completely, and a large amount of exhaust gas and fuel residue are sucked into the air intake, which causes a significant reduction in the oxygen content entering the fighter jet's engine, resulting in engine shutdown!"

Xie Wei's explanation made everything clear to everyone.

Yes!

The J-7 has an air intake in the nose.

The air intake itself is not very large.

In the oxygen-deficient environment at high altitudes, the intake of a large amount of missile exhaust gas and incompletely burned waste into the engine causes a sudden drop in the oxygen content in the engine's combustion chamber.

It would be strange if the engine didn't shut off!

"So, even if the J-8 doesn't deflect when launching the improved PL-4 missile, it will still face the problem of engine shutdown?"

Liu Zhimin asked Xie Wei with a serious expression.

"Correct!"

Xie Wei nodded affirmatively.

Although the J-8 has two engines, it also has a nose air intake.

The air intake is already small.

Following the missile's flight path, the ingestion of a large amount of missile exhaust gas can lead to insufficient oxygen content in the engine's combustion chamber, causing the engine to shut down.

"This……"

Liu Zhimin frowned immediately. "Does that mean only the J-8II can use the PL-4? But if two or more are fired in quick succession, it could easily cause both engines to shut down..."

The biggest improvement in the J-8II's appearance was the change from the J-8's nose air intake to side air intakes. This not only provided more space for the airborne radar but also enlarged the air intake channels, allowing more oxygen to be supplied to the combustion chamber, increasing the combustion chamber temperature, and thus improving the fighter's flight performance.

If two missiles are launched simultaneously, and exhaust gases are drawn into both air intakes, the same problem will still occur.

"Such problems are actually easy to solve. They can be avoided without modifying the fighter jets!"

Xie Wei said calmly.

Not a big deal.

The reason for this problem is that there is too little experience in this area in China.

The People's Republic of China had only been established for 30 years. Its first high-subsonic jet fighter, the J-5, and its first supersonic jet fighter, the J-6, were primarily armed with cannons for air combat, and had no matching air-to-air missiles.

It wasn't until the Soviet Union provided China with the complete technology transfer for the MiG-21 and its matching K-13 air-to-air missile that the Chinese Air Force's combat weapons began to move from machine guns to missiles.

The reason the Soviet Union gave China the K-13 was definitely not out of any brotherly friendship. Rather, the K-13 was because China provided an unexploded AIM-9 Sidewinder air-to-air missile sample that had been dropped by a Kuomintang Air Force F-86 Sabre fighter jet. The Soviets then reverse-engineered the K-13.

The J-7 is a copy of the MiG-21, while the J-8 is a twin-engine MiG-21.

In this context, it is perfectly normal that the R&D personnel did not encounter any instances where missile launches caused the fighter jet's engine to shut down.

"How to deal with it?"

That's what you said!

Not only the people from Institute 601, but even the test pilots present wanted to slap Xie Wei twice to tell him to stop keeping them in suspense.

"Change flight attitude immediately after launch!"

Xie Wei proposed the simplest solution, which did not require modifications to the fighter jet's air intake or the missile's launch method.

He needs to test the performance of the improved PL-4 as soon as possible to secure an Air Force order and prevent the introduction of the Python-3 air-to-air missile, which is inferior to the improved PL-4.

1500 sets, that's $5 million!

The unit price exceeds $33, and of course, this includes the production technology.

The domestically produced improved PL-4 only costs tens of thousands of yuan to produce. Even if it is sold to the Air Force for 15 yuan each, it would be a worthwhile deal for both sides.

The profits generated from orders of thousands of units can not only fund the manufacturing plant's technology upgrades, but also provide the R&D team with continuous R&D funding.

"Change flight attitude?"

A test pilot frowned. "Correcting the launch deflection is never easy..."

"What if we use the deflection direction to maneuver to the side directly based on the deflection torque?"

Xie Wei directly drew the other direction of force on the stress structure, "Wouldn't the fighter jet be easier to control in this way? And it also avoids the nose air intake from sucking in a lot of exhaust gas."

"What if two shots are fired in quick succession? In aerial combat, such a situation is not uncommon, but it is not rare either."

A test pilot in his early forties looked worried.

Dogfighting between fighter jets is a compulsory subject for all pilots, and close-range dogfighting is currently the main training content for fighter pilots.

"A steep ascent..."

Xie Wei drew another force structure diagram and looked at the pilots, saying, "While climbing, we need to balance the fighter jet, so the operation is a bit more difficult."

Xie Wei is not a pilot, but he is now familiar with the relevant technologies of fighter jets and missiles, and he also frequently participates in the research of quadruple redundancy fly-by-wire control systems.

They have a very clear understanding of the fighter jet's maneuverability in the air and how to operate it.

After listening, the test pilots did not raise any further questions.

"Is that so? The J-8 is much heavier than the J-7, which makes its maneuverability in the air..." Liu Zhimin frowned.

The J-8 is a twin-engine aircraft with a maximum takeoff weight of nearly 20 tons, which naturally makes it much more difficult to control.

To make operation more difficult in order to equip it with air-to-air missiles?

"Changing the flight attitude is only one aspect. The best solution is to improve the launch method. Next, we will improve the launch method of PL-4, changing from the current orbital launch to an off-orbit launch, so that the engine will ignite after the missile has been separated from the weapon pylon for a certain distance."

Xie Wei's gaze swept across everyone's faces, taking in all their reactions.

Non-orbital launch is mainly used for air-launching missiles with longer ranges and greater weight.

This type of missile has a more powerful engine thrust, and the solid fuel propellant burns rapidly during launch, producing a strong exhaust flame.

With the greater thrust of medium- and long-range rocket engines, the fighter jet deflects more sharply.

By first detaching the missile from the pylon and then igniting the engine, the impact on the fighter jet is greatly reduced.

Besides, stealth fighters have their missiles inside their bomb bays!
After a moment of silence, he said, "The improved PL-4 prototype needs to be test-fired!"

The test pilots' expressions changed drastically in an instant.

Especially the test pilots of the J-7.

Even though they were experienced and had a very strong reaction capability, no one was willing to test-fire this air-to-air missile, which had repeatedly caused the engine to shut down, from the J-7 during its test flight.

Even though Xie Wei analyzed the causes of the problem in great detail and his proposed solutions were accepted by them.

It's not that I'm worried about it affecting my future.

Rather, they were worried about causing losses to national property. Losing a J-7 could mean losing millions of dollars, and no pilot could bear such a result.

"I come!"

The technical conference room fell silent, as no test pilot was willing to fly the J-7 into the air to test fire the PL-4 again. A test pilot, about twenty-seven or twenty-eight years old, stepped forward with a determined look on his face.

"Lei Qiang, are you sure?"

Lai Guichang frowned as he looked at the other test pilots who were turning their heads to look in other directions, before seriously asking Lei Qiang.

Lei Qiang?

Lei Qiang, the first test pilot of the J-10 fighter jet, is an "Air Force-level test pilot" who has been engaged in test flights for 23 years and has flown 22 types of aircraft.

How did such an amazing person end up here?

Moreover, Lei Qiang was originally a pilot. After Project No. 10 was launched, he was selected along with 17 other pilots to receive training and screening in Chengdu.

When did history change?

Moreover, Lei Qiang truly distinguished himself during the air test launch of the Python 3 missile carried by the J-7. It was during this test launch that Lei Qiang successfully launched the Python 3, preventing the engine from stalling after the fighter jet failed to launch and leaving the test team at a loss. This allowed the test team to understand the cause of the situation – the missile engine thrust was greater than the fighter jet engine thrust!
It has to be him!
"Professor Lai, when I chose to become a test pilot, I was already fully prepared mentally!"

Lei Qiang said with a determined look, "Although I haven't been a test pilot for long and my experience isn't extensive..."

"Okay, you're the one! Get ready, the test is tomorrow!"

Xie Wei spoke up.

"Xie Wei!"

Lai Guichang became anxious.

Xie Wei was unaware of the situation. Lei Qiang was the youngest test pilot, but his experience was not as rich as that of the other test pilots. He was still in the training stage, and new test pilots would not be assigned to difficult or dangerous test flight missions.

He was worried that Xie Wei might not understand the situation, and under the current circumstances, an experienced test pilot would definitely be a safer choice.

This is a responsibility to the future of the project, and also a responsibility to the lives of the pilots.

"Professor Lai, let's leave it at that! PL-4 can't wait any longer."

Xie Wei knew what Professor Lai wanted to say, and turned to Lei Qiang, saying, "During the test launch, if an accident occurs and the fighter jet cannot be saved, I hope you will prioritize your life. As for the crashed fighter jet, we will compensate for it! If you cannot do this, then you don't need to carry out this mission."

"what?"

Everyone was stunned.

Everyone knows how valuable fighter jets are.
Before the mission even began, Xie Wei demanded that the test pilots prioritize their personal lives.

Under the current circumstances, everyone believes that pilot training is easy, but fighter jets are more valuable!
Lei Qiang panicked.

Fighter jets are so valuable!
How can an individual's life take precedence over the interests of the nation?
“Every pilot is the nation’s most valuable asset! Fighter jets can be rebuilt if they crash, as long as there’s money. Pilots with hundreds or thousands of hours of flight experience are far more valuable than fighter jets! Not to mention test pilots? Who here hasn’t lost a few engines? Have you ever calculated how much an engine costs?”

Xie Wei's voice wasn't loud, but it went straight to the heart.

These days, nobody's bothered to do the math.

Just because they're poor.

"So, you can consider it. I think that as long as someone is willing to cover the costs, factories 132, 112, 601, and 611 will not refuse to crash a few fighter jets!"

As Xie Wei spoke, his gaze swept over everyone again.

After saying that, he walked outside without waiting for anyone's reaction.

Lai Guichang quickly caught up with him: "You're not confident about another test launch? How about we wait a bit longer and change the tracked launch to a separate launch..."

"No one is 100% certain. A pilot's life is even more precious."

Xie Wei emphasized this.

Theoretically, there is no problem.

But in reality, when accidents happen, no one can control them.

As the first test pilot of the J-10, Xie Wei was able to fly 22 different aircraft types during 23 years of test flights. Such a talented person would be a sinner to the entire country if an accident were to happen to him!

"Switching to non-orbital launch would indeed be safer, but we really don't have time. The Air Force is already in contact with Israel, preparing to acquire the Python-3!"

Xie Wei told Lai Guichang that PL-4 must be tested as soon as possible.

It can be successfully launched, and then live-fire target practice will be conducted.

If the PL-4 can shoot down targets at a distance of 20 kilometers, and the Air Force does not place orders, Li Rui will have no way to stop the PL-4 from being sold on the international market.

"Shouldn't we invite the military leaders to visit?"

Lai Guichang also knew that PL-4 was in a very dangerous situation and that the Air Force could no longer wait.

The fighter jets are not advanced enough, lagging behind the international standards by a whole generation or even more; the supporting missiles are also not advanced enough, as others can launch missiles beyond visual range, and if a real war breaks out, there will be no chance to fight back.

"No need for an invitation. Let's complete the fighter jet separation test first, and only proceed to the next step after ensuring there are no problems. Once this is settled, we can invite the military leaders to visit."

Whether or not military leaders are invited to visit is not important at this time.

Xie Wei just wanted to know as soon as possible whether the Air Force would place an order with him.

The day of Yitzhak's departure is drawing ever closer.

(End of this chapter)