Return to 2000: Captain of the Great Powers

Before the final approach fix on the fifth side of runway 28 of Qitai Airport, a Boeing 737 was already in level flight, preparing to join the glideslope after the final approach fix.

Chen Guoli and an instructor from National University Airlines teamed up to verify the single-engine procedure on runway 28 of Qitai Airport.Only one side of Qitai Airport has ILS, and the other side has no instrument landing system.

There is no instrument landing system on the other side of the runway, just because the opposite runway is just facing the Tianshan Mountains, and there is basically no space for approach.

Qitai Airport had no civilian purpose at the beginning of its construction. Moreover, due to the poor location of the airport, all kinds of navigation facilities at the airport are the most basic. In addition, Qitai Airport is often windy and snowy, so it can often be completed in a short time The pavement is covered inside, making it difficult to obtain visual references.

The general captain of this kind of airport can't handle it at all, and even the younger instructors can't do what they want. Only the top part of the people have the possibility of landing safely.Therefore, this verification is destined to be only a final backup plan for some special cases.

Chen Guoli and Chen Guoli took off from Shule Airport, and they could see the entire Tianshan Mountains as soon as they took off. After turning over a gap in the mountains, they had already arrived at Qitai Airport.

The straight-line distance between the two is very short, and the voyage is only half an hour. The only obstacle is the Tianshan Mountains.

Since Qitai Airport is close to the Tianshan Mountains, the terrain conditions in its approach area are extremely complicated.The initial approach fix point is just after the top of the Tianshan Mountains. Therefore, after passing the initial approach fix point, the altitude cannot be lowered immediately, and the altitude needs to be maintained all the time.However, due to the need to delay the timing of the descent, the final stage has to maintain a descent rate of [-] to [-] feet per minute until the fourth turn.

Descent rates below [-] ft/min make it impossible to intercept the glideslope normally at the final approach fix, and rates above [-] ft/min can easily cause terrain warnings, especially cuts After four sides, a terrain warning is almost certain to be triggered.

However, due to the reminder from the technical department and the extreme caution of Chen Guoli and the others, the situation was good until the moment of the slide.

"There is an obstacle that needs to be paid attention to at five miles and six nautical miles. According to the feedback from Qitai Airport, the blind landing slideway is unstable, so why don't we press the APP for a while?" NUS teacher asked.

The instability of the blind landing signal at Qitai Airport is not the cause of the equipment, which has been concluded after many inspections.The only explanation is environmental factors, such as wind and snow.

But in fact, even in the case of heavy snowfall, there are few problems affecting the ILS signal at other airports. This statement is actually not very convincing.However, fortunately, the instability of the blind landing signal at Qitai Airport is relatively small, and in view of the special situation of Qitai Airport, in the end, this matter was turned a blind eye and acquiesced .

If it is at Pingyuan Airport, it is not a big deal if the blind landing is occasionally unstable.However, given the complex terrain of Qitai Airport, one must be careful.Unstable blind landing signals may lead the aircraft to a sudden descent rate. Once it hits the terrain on the fifth side, the risk factor is a bit too high.

Therefore, in the face of this situation, not pressing the APP mentioned by the instructors of National University Airlines is a solution.

The most threatening thing in the final descent stage of Qitai Airport is a mountain peak in six nautical miles. Basically, after passing this peak, even if there is a sudden and large descent rate later, it will not really cause too much danger.

And according to the feedback from the airport, at low altitudes, the ILS signal is more stable.Therefore, as long as you pass the six-nautical-mile hill, you will be much safer behind.

Since there are obvious IDS instability from the final approach fix point to five sides and six nautical miles, and they are mainly concentrated on the glideslope, then the G/S method is not used, but the manual V/S is used to follow a rough descent trajectory .

Blind landing signals, especially unstable glideslope signals, usually manifest as a sudden twitch of the glideslope signal point, sometimes below, then the autopilot will think that the aircraft is higher than the standard glideslope, and a large descent rate will be generated in anticipation To catch up with what it considers to be the standard glideslope, resulting in an unexpected large descent rate of the aircraft, causing terrain effects.

However, the twitching usually only lasts for a moment and does not last for a long time.Thus, the crew can manually push out a steady rate of descent with roughly reference to the glideslope signal.In this way, even if the glideslope signal becomes nervous for a short time, the aircraft will still descend at the previously set descent rate without the G/S and AP connected, and there will be no steep descent.

However, this only applies to brief glideslope instability.If the time is too long, the pilot will not know whether he is still on the standard glideslope.After all, the speed of the aircraft is constantly changing slightly, and there is also the influence of airflow. If you want to always stay on the standard glideslope, it is impossible to meet it all the way with a constant descent rate.

In a short period of time, even if there is a deviation, the gap will not be very large. After the glideslope signal is stabilized again, the descent rate can be corrected.However, if the glideslope signal is unstable for too long and the pilot has no reference, it is more dangerous.After all, not everyone can calculate the real-time descent rate based on the ground speed like Xu Cang.

The final approach fix of runway 28 of Qitai Airport is about [-] nautical miles away from the runway head. This is a relatively long final descent stage, and usually this length should be kept at about [-] nautical miles.

The height of the intercepted glideslope is 900 meters.Chen Guoli had done a good job before. After cutting into the fifth edge, he maintained a level flight for a short time, so the workload was relatively small.

"Well, let's establish the shape first. After passing the FAF point, I will push the descent rate." Chen Guoli looked at the airspeed indicator: "The speed is less than 170, and the flaps are 25."

This time the model is not a 737-800, but a smaller 700 model.Therefore, when the flaps are released, after the fifteenth flap, the flap 25 should be released as a transition, while on the 800 model, after the fifteenth flap, the flap thirty can be directly placed.

The NUS instructor looked at the airspeed indicator to confirm that the speed was correct, and then put the flap handle to the 25 position.

Chen Guoli immediately began to slow down, and when the flap indicator reached the position of 25, Chen Guoli barely paused, and directly ordered: "The speed is less than 165, and the flaps are thirty."

The NUS instructors put the flap handle to the last [-] positions as promised.

"21 meters against the wind." The NUS teacher reminded Chen Guoli when he saw Chen Guoli making the final speed adjustment.

As soon as Chen Guoli touched the speed knob, he couldn't help being stunned: "Where's the crosswind?"

"14 meters, positive crosswind. The good news is that you don't need to include it in the wind correction. The bad news is that you have reached the limit of crosswind volume." The teacher of NUS has a serious expression on his face: "Teacher, I'm afraid it's not very easy to fly. what."

At Chen Guoli's age, even this NUS teacher should call him teacher.However, this does not mean that this young NUS instructor is inexperienced. On the contrary, this pilot who can convince everyone in an airline like NUS Airlines is absolutely excellent.

For nothing else, the headwind is 21 meters, and the sidewind is 14 meters. This is quite a headache airflow environment no matter where it is placed.

"Runway braking effect?"

The NUS instructors seem to be well prepared: "Just now there are 4 in the report, but now it is estimated that it is only 3, and it is still snowing outside. Teacher, according to the calculation of the QRH landing distance table, plus a margin of 15.00%, it is just in line with the airport. The length of runway 28 is the same. Instructor, you can’t take the float anymore. If the float is a little longer, the plane may not be able to stop.”

The runway braking effect is an indicator for judging the friction coefficient of the runway surface. It is from 0 to 6. The larger the number, the higher the friction coefficient.Generally speaking, 5 and 6 are better, and runway braking effect 6 generally refers to dry runways.And if the runway braking effect is 0 or 1, it is basically not allowed to take off and land.

It rains and snows all year round at Qitai Airport, so there is basically no dry runway.Runway braking effect 3 or 4 is a normal situation, but it is not Chen Guoli's bad luck.However, the runway at Qitai Airport is inherently short, so if this is done, the stopping distance of the plane will be more dangerous.

However, the five-sided airflow and the stopping distance all gave Chen Guoli unprecedented challenges.No wonder, Bi Lin only wanted to let Xu Cang do it.This is still in the case of two engines. If it is flying with one engine, the difficulty will increase. This is a bit unreasonable, and even Chen Guoli is not sure.

In the end, Chen Guoli set the wind correction to [-]. If it is too large, it will be difficult to control the subsequent approach speed, and it is too close to the bottom of the red and black speed belt, and it is too easy to overspeed.After a while it started to descend, the air flow must be quite unstable, and the wind correction is set too high, and he has almost no room to maneuver.

However, if it is really set according to the headwind, the wind correction of [-] knots must be low, and it is estimated that you should be more cautious about closing the throttle in the future.Otherwise, if it is a little early or fast, the plane will definitely fall down unstoppably.

At the altitude of Qitai Airport, once the plane starts to sink a lot, even if you put on the gas, it will not be very easy to save it.

Seeing Chen Guoli's dignified profile, the NUS teacher suddenly made a suggestion: "Teacher, do you want to use the flaps to land forty?"

In theory, both flap [-] and flap [-] are normal landing configurations.However, most people are not very good at using flap forty, and there are many reasons involved.However, the most intuitive change when using flap [-] is that it can effectively reduce the approach speed, which undoubtedly greatly helps shorten the braking distance.

However, if flaps [-] are used, the speed range will be reduced, which further reduces Chen Guoli's control space.Under the low-altitude turbulence behind, Chen Guoli needs to maintain the airspeed more accurately, otherwise it is easy to cause overspeed or stall.

Chen Guoli could understand the intention of the NUS faculty, but after thinking about it, he finally refused.He wasn't confident that he could really maintain accurate airspeed at low altitude.

At 0.2 nautical miles before the FAF, Chen Guoli launched a descent rate of 950 feet per minute with reference to the ground speed.At such a height, the ground speed is relatively large, so that the standard rate of descent will be relatively large.However, the descent rate of 950 feet per minute in a normal configuration is really outrageous. It can be seen that Qitai Airport really cannot be measured by common sense.

The reason for the advance is that it takes a certain amount of time for the aircraft to establish its descent rate from level flight. If it really waits until it passes the final approach fix, then the timing will be too late.

However, in fact, 0.2 nautical miles ahead is also a bit late.At least when the plane passed the final approach fix, the plane's descent rate was just over seven hundred feet per minute.This is also the reason why Chen Guoli's initial decline rate is relatively large.

About five seconds after the descent rate of 950 feet per minute was actually formed, it was clear that according to the glideslope signal, the plane was on the standard glideslope, but Chen Guoli reduced the descent rate to [-] feet per minute in advance.

Pilots should not only pay attention to the glideslope signal, but should adjust the descent rate in time after referring to the ground speed change and all advances, so that the aircraft can obtain a soft and consistent glide path.

In fact, if the required navigation performance technology is popularized and matured, the computer can calculate the specific value of the aircraft's deviation from the standard glide path on the fourth page of the progress page, and even provide a reference descent rate value.

However, this glideslope is calculated by GPS signal, which is slightly different from the signal provided by the ISA, especially when the temperature deviates too much from the ISA, the greater the deviation, the greater the gap between the two glideslopes .

According to the temperature of Qitai Airport, there is indeed a gap between the two, but there is still a certain reference value.

This manual operation of chasing the glideslope is not too difficult for an instructor of Chen Guoli's level. It is no stranger to occasionally need to use this technique when flying to some complex airports.

However, due to the turbulent airflow on the final side, Chen Guoli needs to always correct the throttle in order to keep the airspeed within a relatively stable range.

After passing six nautical miles, Chen Guoli pressed the APP button, the aircraft intercepted the glideslope, the value of the descent rate window disappeared, and the autopilot began to automatically correct the descent rate according to the blind landing signal.

"Control Tower, 1533, No. 28 has landed blindly."

Since this is not a commercial flight, the call sign is only replaced by the aircraft number.

"1533, now the surface wind is 310/16, the gust is 18, the runway is wet with light snow, and the sea pressure is corrected to 1031, you can land, pay attention to the airflow from all sides."

"Corrected sea pressure 1031, runway 28, can land, 1533."

As soon as the NUS teacher finished repeating the recitation, Chen Guoli cursed secretly, and the wind became stronger and stronger.The autopilot just barely keeps up, but the autothrottle just can't keep up.

Comparing the automatic throttle of the Boeing 737 with the 320, it is almost like a mental retardation, so that Chen Guoli needs to constantly intervene in the throttle.When it was about a thousand feet above the ground, Chen Guoli couldn't take it anymore, so he directly disconnected the auto accelerator, and controlled the accelerator by himself.

However, the moment the auto throttle was disconnected, the autopilot could no longer withstand the influence of the airflow and disconnected by itself.

At the sound of the alarm that the automatic driving was disconnected, Chen Guoli immediately took hold of the steering wheel with his left hand.Regarding this point, Chen Guoli was somewhat prepared, so even when the autopilot was turned on, his left hand never left the steering wheel, which made it possible for him to take over the plane immediately when the autopilot was suddenly turned off.

However, as he flew manually, Chen Guoli couldn't help but see cold sweat on his forehead.The plane is like a small boat on the top of the waves, bumping up and down, left and right, violently and irregularly.He has set the wind correction value relatively small, but the airspeed is still close to the bottom of the red-black speed band from time to time, sometimes it is lower than the Vref speed, and close to the yellow zone speed.

"What the hell is this!"

Chen Guoli cursed involuntarily while concentrating all his energy on controlling the plane.He has been flying civil aviation aircraft for more than 20 years, and this is the first time he has encountered such a chaotic airflow. No wonder the autopilot can no longer maintain it.

However, Chen Guoli really has real kung fu.Even if the airspeed is flying up and down, every time it is overspeeding or stalling, but it always stops at the last moment, and the speed is always changing within the specified range. This is also very good.

After passing through [-] feet, the strength of the airflow increased instead of decreasing, and Chen Guoli almost couldn't hold it anymore.Moreover, due to the extremely strong crosswind, the nose of the plane was not facing the runway, but approached sideways at an exaggerated angle of almost thirty degrees.

"One hundred is decisive." NUS teacher felt sweaty palms even watching from the sidelines: "It's about to hit the ground, let's hold on for a while teacher!"

At this moment, the barometric altitude is three hundred feet above the altitude of the airport, and it is close to landing.

"Hold!"

Chen Guoli was going crazy, but he still gritted his teeth and tried his best to bring the plane down.The only reason for the two of them to go down is that no matter the speed, course, or glide path are within the deviation limit, according to the regulations, they can continue to go down.

I have to say that Chen Guoli really has solid skills.

At a height of one hundred feet, the turbulence finally became smaller.

Chen Guoli yelled: "Go-fly listens to my password, monitors the missing items, and takes action decisively when necessary!"

In such an environment, even if it is Chen Guoli, even though he has already reached a height of [-] feet, he is still not sure whether he can land, and he must be ready for a go-around at any time.Moreover, what's even more terrible is that in the low-altitude environment, the turbulence is smaller, but the crosswind volume has increased strangely.

Originally, the drift angle was very large, but now the direction of the nose of the plane and the center line of the runway produced an angle of more than [-] degrees, which was simply terrifying.

However, Chen Guoli was also skilled. Before the plane's radio altimeter reported ten feet and was about to land, he kicked the left rudder and straightened the nose in the air.This kick alone is a hard work.

Many pilots, even the captain, dare not push the rudder in the air, but wait for one wheel to touch down first, and then straighten the plane before the other wheel touches down. How can there be Chen Guoli who is so straight in the air?
Even the NUS teacher on the right seat saw Chen Guoli's rudder operation, his eyes lit up, and he couldn't help admiring: "It's amazing!"

Chen Guoli had already done a good job, he almost straightened the plane with one kick, but he was not Xu Cang after all, he couldn't push the nose of the plane perfectly.In normal times, this slight difference is harmless, but for a slippery runway like Qitai Airport, this slight deviation is fatal.

The left landing gear of the aircraft touched down slightly earlier than the right landing gear because it was not fully pedaled.One-wheel touchdown is a common situation in strong crosswinds, but as soon as the left landing gear hit the ground, it failed to catch the road surface, but produced a very obvious sideslip.

In the cockpit, after feeling an obvious sense of grounding, Chen Guoli can rely on the centerline of the road surface as a reference, and he can already see the subtle flaws he corrected.He was about to straighten the plane completely, but suddenly, the entire fuselage of the plane slid sideways to the left.

Chen Guoli turned pale with fright, without even thinking about it, but fortunately he didn't pull the reverse jet, he filled up the gas pedal, and shouted: "Let's go!"

"It took four tries before it fell?"

At the door of the preparation room, Xu Cang listened in disbelief to Lu Jinghua's description of what happened at Qitai Airport.

After Chen Guoli's go-around, he tried again, but the second time he didn't even break through the decision height, so he went around because of the large deviation of the plane's state.After turning around again, Chen Guoli asked the teachers of the National University of China to try again, but it was also unsuccessful.For the fourth time, Chen Guoli was allowed to come, and finally he was barely able to fall.

For a pilot of Chen Guoli's level, it was rare for him to go around so many times before landing.

"I heard that after Teacher Chen came down, his shirt was soaked. You know, Qitai Airport is more than ten degrees below zero. The teacher from the National University turned pale." Lu Jinghua also found it incredible, because he still knew the National University The teacher, who is not an idiot, but a real capable person, can be frightened like this.

"Is it so difficult to fly?" Xu Cang knew that Qitai Airport was difficult to fly, but he didn't expect that it would be so difficult to fly and put so much pressure on the two teachers.

"It seems that the teacher from the National University of China refused the subsequent single-shot verification after landing." Lu Jinghua said.

According to the plan, after the aircraft flew to Qitai Airport, it will undergo a single-engine verification after minor repairs.However, both of them fly so frightenedly, how can they fly with only one, isn't that courting death?
Based on this idea, the faculty members of NUS directly refused to take off.As a result, the crew is short of one person, which is difficult to handle.

Xu Cang sighed: "Are you scared out of your wits?"

It is estimated that this teacher will have a psychological shadow on Qitai Airport in the future.

Suddenly, Lu Jinghua said, "What about you?"

"Me? What's wrong with me?" Xu Cang was taken aback for a moment, and immediately thought of the previous agreement with Bi Lin, and suddenly felt that something was wrong.The moment Xu Cang thought of it, his cell phone rang suddenly.

Xu Cang looked at the vibrating phone, gritted his teeth, and connected it anyway.Before he could speak, Di Qingquan's voice came from the opposite side: "Xu Cang, do you know about the Qitai Airport?"

"Understood." Xu Cang said in a low voice.

Di Qingquan's tone was extremely dignified: "If it's convenient, come to Shule as soon as possible, it seems that you have to go out!"