Chapter 172 The God of Death lowers his eyes! He changes his fate against the will of heaven! (Please subscribe!)

"Actively relieve pressure?" Tan Heling looked at Xu Cang incredibly: "You mean to manually relieve pressure after wiping the tail of the aircraft? What if the aircraft exceeds 10,000 feet?"

"Then follow the pressure relief procedure." Xu Cang was paying attention to the status of the plane while answering Tan Heling's questions.

Although the situation is quite dangerous this time, the situation has finally been controlled so far. The restricted pitch and manipulation has caused certain difficulties, but for Xu Cang's side, this problem is still acceptable.

The real fatal problem is the damage to the tail of the machine. Fortunately, there is no ductility problem now. What Xu Cang pays more attention to is whether the damage to the tail of the machine will further lead to pitch control.

The most terrifying thing now is that the elevator has completely failed. After all, some of it has been separated in the control report. If more parts are separated, the consequences will be unimaginable.

In turn operations, some additional means can be used to complete, such as ailerons, such as rudders. However, the rudder is mainly used for yaw operations, and in turn, the rudder only plays an auxiliary role.

However, if there is aileron problem, the rudder can still complete the plane's turn to some extent. However, the efficiency is far lower than that of the aileron.

However, it is difficult to have backups in pitch operation, that is, if the elevator fails, the pilot will not be able to assist in pitch control through the movement of other rudder surfaces. The only feasible solution is to increase or decrease the thrust.

However, the method of increasing and decreasing thrust is difficult to accurately control pitch, and this is the same even if Xu Cang does it.

The only thing that is thankful is that although it seems very dangerous, no danger occurs. If this state continues, it will not be very difficult for the plane to land.

It is precisely based on such a stable mentality that Xu Cang has the energy to talk to Tan Heling to be related to the issue of actively relieving pressure.

"You mean that even if the plane does not release pressure, we have to open all the outflow valves directly. Once the plane rises to more than 10,000 feet, isn't that the incident that caused the plane to release pressure?" Tan Heling still couldn't understand Xu Cang's logic. Isn't this causing trouble for himself?

However, Xu Cang was not shaken at all: "The two harms are only about the minority. In the case of possible damage to the fuselage, the existence of the supercharged system will aggravate the degree of damage to the fuselage, so this danger must be removed."

"Even if it is artificially caused to relieve pressure?" Tan Heling asked back.

Xu Cang's eyes drooped slightly: "The Boeing 737 does not have damage detection of the fuselage structure. As long as there is doubt, it must be regarded as having occurred. The risk generated by prepared pressure relief is less than the damage to the fuselage."

Tan Heling was speechless for a moment. He felt that Xu Cang said something seemed to make sense. However, this also had an unavoidable problem.

"However, there is no relevant active pressure relief program operation in the machine tail program. You are violating the standard program."

Xu Cang's eyes shone with a bright light, which contained in them with great firmness: "So Boeing's operating manual needs to be changed."

Tan Heling and Mo Shangyun were both shocked. Xu Cang's words clearly pointed out that Boeing's standard operating procedures were flawed. In this era, whether from bureaus, airlines, or to the lowest-level pilots, although they sneered at Boeing's commercial practices, they never denied their professionalism and regarded their operating procedures as the standard. How could Xu Cang say that the Boeing manual needs to be changed?

"Xu Cang, are you telling the truth?" Tan Heling still couldn't believe that Xu Cang dared to say that. Not to mention that Xu Cang is now a second-level co-pilot, even the chief pilot of the Civil Aviation Administration would not dare to say this.

However, Xu Cang did not answer Tan Heling's words directly, but said softly: "Don't worry, you won't have any problems. It's because there are problems with the program, not because you have problems."

Tan Heling's body trembled, and Xu Cang clearly saw through his little thoughts. He asked so persistently that he was afraid that he would transfer the booster method to the artificial station under the inspection order just now, and then completely closed the outflow valve.

Judging from Xu Cang's meaning, the plane explosion was directly related to his manual closing of the outflow valve, which was what Tan Heling was the most uneasy. But Xu Cang now said that Tan Heling had no problem.

Even though Tan Heling knew that the final result was decided by the bureau, he was relieved when Xu Cang said this and said, "Thank you."

"Okay, prepare for approaching." Xu Cang adjusted his mood and continued: "It is not difficult to land this time. The problem of limited pitch operation is still concentrated on the nose of the aircraft. Therefore, during approaching operation, try to be careful not to generate too sufficient aircraft energy. Others are not big problems."

Now the wheel is suppressed so that you can only push forward or pull back for a short period of travel, but this does not mean that the difficulty of lowering your head and raising your head is the same.

Since the stability surface matching has been pushed forward to the end, the most direct way to use the aircraft to lower its head is to hold the wheel, but this method is limited.

On the contrary, if you want to raise the plane, although pulling the wheel backwards is also limited, you can assist in lifting the plane by tying the stability surface to help lift the plane, and this method has been unlimited so far.

Therefore, given the inconsistent difficulty of lowering the head and raising the head of the aircraft, Xu Cang needs to try his best to avoid possible situations where the aircraft head is destined to bend downwards at a large extent, which means that Xu Cang said that the aircraft energy is too sufficient.

When the energy is too sufficient and full, the pilot has to rely on uninterrupted pole pushing to maintain the aircraft's trajectory always on the correct glide path, which is obviously inconsistent with the current difficulties of the aircraft.

"I will enter the field with a relatively small energy state, and there may be low altitudes of three reds and one whites or four red lights on the runway. As long as the aircraft status data deviation is not particularly large, don't call for re-flight. Our pitch operation is now limited. If possible, try not to re-flight."

It can be seen that Xu Cang is still prepared for the upcoming approach process. Generally speaking, under the reference of the PAPI lamp, two reds and two whites are naturally the most standard downward trajectory.

However, in actual flight, at low altitudes, such as when you are about to enter the runway, if you still follow the two red and two white standards, then it is very likely that you will not fall into the "big white block", that is, the standard connection area.

This is because the standard downward trajectory is indeed in the docking area, but the downward trajectory of the aircraft cannot objectively achieve a straight line, mainly because the aircraft has a flattened curve at the end.

If the aircraft is always in the opposite direction, once the leveling is finally done, the actual effect will almost certainly pass the receiving area. Therefore, in actual flight, the pilot will perform some additional operations, such as when it is about to land, artificially put the aircraft downwards and deliberately lower the trajectory of the aircraft, so that the aircraft can fall to the receiving area as soon as it is leveled.

Also, move the timing of this action forward, that is, when entering the runway, abandon the standard downward track and enter the field at a low altitude of three reds and one whites. The subsequent operation is normal and you can detach the aircraft without any need, so the grounding point will be standard.

Xu Cang undoubtedly wanted to choose the latter method because given the restricted state of pitch and manipulation, he might not be able to complete the action of descending the plane at the last moment. So, all he had to do was change the entry height and enter the field at a lower height.

Anyway, he can accept low energy and low altitude, but cannot accept high energy and high altitude landing.

With Xu Cang's skills, it is logical that PAPI lights can be entered in three reds and one whites, but avoid some unexpected situations, such as the low entry height causing four red lights. Xu Cang still needs to explain to Tan Heling and Mo Shangyun in advance, so as not to let the two people shout for refly because of the entry height.

It’s not that the plane cannot fly again now, it’s just that it’s a bit troublesome. As long as it’s not a forced one, Xu Cang doesn’t want to fly again. Moreover, the state of large thrust and high elevation angle for the plane has a large aerodynamic load, which may not deteriorate the damage to the plane. This is the most fatal thing.

"Don't you care about the four red lights?" Tan Heling asked.

Xu Cang shook his head: "Don't worry! It's easy to correct if it's flying low, but it's difficult to correct if it's flying high. If it's flying into four white lights, then it's better to fly again."

Since Xu Cang said so, Tan Heling and Mo Shangyun had no objection, and they could understand Xu Cang's idea, which was considered to be the same as the three of them.

"Make a get-to-face preparation." Xu Cang ordered.

"Okay!" Tan Heling immediately made preparations for approaching. This preparation is not complicated. The course and blind landing frequency were adjusted before taking off, and the determination altitude was the same. Tan Heling only needs to select automatic brakes. However, when the automatic brake is selected to three, the automatic brake release preset light is always on.

"Hmm?" Tan Heling turned the automatic brake knob back to the close position. After waiting for three or four seconds, he chose the gear of automatic brake three again. After waiting for a few seconds, the automatic brake release preset light illuminated again.

Tan Heling tried again, but the result was still the same.

Xu Cang was still paying attention to the aircraft's control. After Tan Heling tried to set up automatic brakes several times but failed, he finally noticed them and asked casually: "Is there any problem with automatic brakes?"

"It seems that I can't set it up." Tan Heling set up the automatic brake in front of Xu Cang again, but the preset light still lit up stubbornly.

Xu Cang tried it himself, but the result was still the same, so he simply ignored it: "Forget it, I use artificial brakes as well."

"Oh, then you're ready." Tan Heling quickly scanned the lower panel from top to bottom and confirmed that the settings were completed: "Then I'll make a quick Jian Ling?"

Just as Xu Cang was about to agree, Mo Shangyun sat behind him and spoke: "Xu Cang, how do you think the pole strength now?"

"Room power? No." Xu Cang raised his eyebrows and soon realized what Mo Shangyun said. He quickly let out his right hand, pressed the SYS button, and immediately displayed the hydraulic information on the lower DU that originally displayed the engine data.

When the hydraulic page appeared, Xu Cang's eyelids twitched.

"The hydraulic pressure is lowering?" Tan Heling, who was next to him, came closer: "It dropped so quickly! Teacher, is it because the hydraulic pressure is lowered that the automatic brake cannot be pre-positioned?"

"The pressure of the system B is directly related to automatic braking. However, this is not the biggest problem." Mo Shangyun's tone was still normal: "This is not the hydraulic pressure being reduced, but the hydraulic oil being leaking out."

Xu Cang cursed inwardly, and Tan Heling also reacted: "Is the tail of the machine broken and connected to the hydraulic pipeline?"

"Otherwise?" Mo Shangyun sighed: "Broken fuselage will cause so many problems."

Whether it is hydraulic pipelines, fuel pipelines or electrical pipelines, they are distributed in the fuselage structure. As long as there is physical damage, it will inevitably extend the damage to other systems, rather than just a problem of boosting.

With the explosion not long ago, any normal person could understand that the damage to the fuselage structure would be extremely serious, and the damage would spread beyond imagination.

Tan Heling watched as the pressure on the AB system was decreasing rapidly, and couldn't help but worry: "Xu Cang, do you still have difficulties in manipulating it?"

The rudder surface control of the Boeing 737 uses hydraulic pressure to eliminate excess rod force. Once the hydraulic system fails, the pilot must directly control the rudder surface through the mechanical structure, and the required force is very large.

Xu Cang moved the driving wheel a little and felt that the situation was still good: "It's okay, let's land as soon as possible. Who knows if there will be any other faults?"

In Xu Cang's idea, the failure of the hydraulic system is not difficult to deal with. Even if the AB system is completely invalid, it will be impossible to manually resume flights.

The difficulty of artificial recovery of flight is never technical, but the pilot's strength is not enough. That's right, once it enters the artificial recovery state, the pilot basically directly controls the flight rudder surface with the help of lack of hydraulic pressure. Under the action of aerodynamic load, the joystick force will be very strong. At that time, the aircraft was a real "air gym".

However, now that the plane is about to land, it is necessary to exercise, and the duration will not be very long. Even with Xu Cang's body, it can still withstand it.

What Xu Cang was worried about was those unknown faults, such as the deterioration of pitch and tilt manipulation, so it was the most important to land as soon as possible.

At this moment, Director Liu's voice came from the tower control frequency: "Xu Cang, is the plane in good condition?"

"There are some minor problems with the hydraulic pressure, and the overall situation is still controllable."

"Okay!" Director Liu breathed a sigh of relief when he heard that everything was normal: "Then you can continue to reach a height of 1,500 meters."

One thousand five hundred meters is the height of the final approach positioning point of the blind landing of Runway 05. According to the procedure, the downhill passage should be intercepted at this height.

"Okay." Xu Cang didn't even do the finished recitation. His eyes scanned the dashboard for a moment, and finally positioned it on the supercharged panel.

At this moment, the cabin is already connected with the outside world, so the height outside is as high as the cockpit. However, the altitude of the aircraft is now below 10,000 feet, but the cabin height warning light is still on.

Tan Heling noticed that Xu Cang was looking at the cabin height warning light and asked: "The height should be less than 10,000 yuan. Do you want to take off the oxygen mask? This warning light is a bit delayed."

"Let's wait." Xu Cang of course knew that there would be a delay in the extinguishing of the cockpit height warning light. The reason why he had not taken off the oxygen mask was mainly because he had begun to feel the hysteresis rod force.

"Damn it!" Just now, Xu Cang took the driving wheel a little back, but just two or three minutes ago, he felt smoothly that he now became like moving forward in the mud, and he could only show extremely subtle reactions.

Xu Cang knew that this was not a jammed again, but the hydraulic pressure had dropped to a limit, so he began to control the rudder surface directly through the mechanical structure of the steel cable.

If this problem is not available, Xu Cang would probably remove the oxygen mask as soon as the plane reaches less than 10,000 feet, but now it's better to wait.

At this height, the air is still thin, and he still hopes to ensure a relatively good condition.

"Xu Cang, the hydraulic pressure is gone. Be careful when doing artificial brakes later and don't light the brakes." Mo Shangyun reminded from behind.

Although there is no hydraulic pressure, brakes are theoretically unusable. But in fact, due to the existence of the pressure storage bottle, it can still provide a limited number of artificial brake pressures.

It is precisely because of the limit of the number of brakes that Mo Shangyun reminded Xu Cang not to light the brakes, because this will quickly consume the pressure of the aircraft pressure storage bottle. Continuous braking is the correct way to deal with it.

"I know." Xu Cang nodded.

He looked at the altimeter that was less than 8,000 feet, and the cockpit height light under the delay was also turned off. Xu Cang saw that it was almost done and pointed at Tan Heling: "I will take off the oxygen mask first and hand over the control."

Tan Heling immediately put the plate in both hands: "Receive the manipulation!"

Seeing that Tan Heling was ready, Xu Cang took off the oxygen mask with both hands, sorted out his messy hair slightly, put on the headphones again, switched back to the MASK electric gate, and then said to Tan Heling: "Receive the manipulation! Take it off!"

Xu Cang grabbed the driving wheel with his left hand. When Tan Heling took off his oxygen mask, he conducted a passenger broadcast: "The plane is about to return to Jianchuan within five minutes. You can take off your oxygen mask. Please fasten your seat belt."
To be continued...