Xu Qing's front foot was still reviewing the procedures for qi source initiation and cross-infusion qi initiation, but he felt that as far as his eyes could see, it was slightly darker. Because the sun has risen at this time, it will not make the cockpit press down all at once, but the change in light is still relatively obvious.

He keenly caught the slightest hint of a switch jumping open in his ears. This is very slight, but Xu Qingqing has heard all kinds of warnings, and he is extremely sensitive to the slightest abnormal noise on the plane, so he immediately put down the electronic manual and turned his head to look at the panel.

This is the habit of pilots, as soon as there is any problem, first look for the panel to see if there is an indicator, the panel can not be found, and then look for the P6 board and P18 board behind the jump switch pop up.

Zhang Qijun was also startled by the sudden darkness of the cockpit, and subconsciously looked for the fault indicator on the panel like Xu Qing.

In fact, Xu Qing and Zhang Qijun can't be regarded as directly going to the panel to find the fault indicator. At first glance, both of them focused on the system signal board, which was next to the main warning light and the fire alarm light, with three indicators lined up side by side.

Unlike the main fire lights, which only have a single function to indicate the fire alarm condition, the system signal board can only cover most of the aircraft's systems, including the flight control system, electrical system, navigation system, APU failure, fuel system, overheat detection system, anti-icing system, power system, hydraulic system, rear roof indicator, cabin door, pressurization and air conditioning system, etc.

When one of the system indicators of this system signal board is on, it indicates that it is on the front roof panel, rear roof or overheated/fireproof panel. An amber light associated with the illuminated system signal has come on.

As long as the system signal sign is on, the main warning light will also be lit to remind the pilot that the two lights are linked. The main reason is that the indication of the system signal board is too small and may be ignored, so a more obvious main warning light is additional.

Generally speaking, the system signal board will only show the amber light outside the pilot's line of sight under normal conditions, and not the one within the line of sight. For example, the airbrake in front of the pilot's line of sight sticks out of the light, but it will not cause the system signal to light up, even if the airbrake sticks out of the light, it is also an amber light.

There are too many indicators in the cockpit, and the pilot can't monitor every indicator all the time, so if the indicator light is on outside the normal line of sight, there will be a system signal board and the main warning light to remind the pilot. Boeing did have a hand in designing airplanes, taking into account the physiology of pilots.

Some people may wonder why the pilot is afraid that the pilot will miss some fault indicators, why not set the alarm sound in the cockpit once the amber indicator light appears, just like the fire alarm, the electric bell is easier to attract attention than the indicator light.

But we have to distinguish why there is such a thing as an alarm, why there is an alarm for a fire, there is an alarm for overspeeding, there is an alarm for stalling, there is an alarm for take-off form, and there is an alarm if the landing gear is not set correctly? However, many other faults have only one indicator?

Failure is a priority, fire alarm this urgent need to deal with the special situation, needless to say, overspeed will cause damage to the body structure, stall is easy to let the aircraft into an abnormal flight state, take-off form alarm indicates that the take-off form is wrong, once forcibly take off, may pose a serious threat to flight safety, not to mention the landing gear warning, to land the landing gear has not all been released, can land?

These are all direct threats to flight safety and need to be dealt with immediately, not only necessary, but also urgent. Conversely, many other faults need to be dealt with, but are less urgent.

If all the failures can trigger an aircraft alarm, it will only increase the psychological stress of the pilot indefinitely. Just the special situation of engine separation will cause the fault indicator light of the electrical system, hydraulic system, flight control system, power system and other aspects to be on, and the alarm is estimated to be uninterrupted when the pilot deals with the special situation.

Another example is during take-off, perhaps due to the relatively small amount of fuel in the central fuel tank, the low-pressure light of the central fuel pump is flashing, and the low-pressure light of the oil pump is also an amber light. What if the pilot interrupts the takeoff because of this? Does the central fuel tank low pressure light shine and need to interrupt the takeoff?

No, you don't!

Therefore, it is necessary to distinguish priorities!

Xu Qing and Zhang Qijun first looked at the system signal panel, but when they saw that the system signal board did not react, the main warning light was also in a state of extinguishment.

Habitually, Xu Qing and the two glanced at the indicator light in front of them, but after looking at it, they remembered that this was not an area for the electrical system.

Boeing's panel arrangement is not random, but each system has its own area, and the area of the electrical system should be on the front roof, and then the two look up at the front roof.

Xu Qing and both of them knew where the electrical panel was, but they didn't find an amber light when they glanced over.

At this time, Xu Qing moved the meter indicator to the position of the ground power supply, and sure enough, judging from the indicator, there was no current coming in from the ground power supply.

"Having a problem with the ground power?" Zhang Qijun also reacted when he saw Xu Qing's movements, and what happened.

Zhang Qijun turned his gaze to the ground power supply available lamp, which was in a dim state at this time. Note that the available light for the ground power supply is blue, not amber, so whether the light is on or not will not cause a reaction from the system signal board.

When the ground power available light is bright blue, the ground power supply is connected and meets the aircraft power quality standards, but now the light is dim, indicating that the aircraft is not connected to the ground power supply.

Now the ground power supply is the only power source of the aircraft, and as soon as the ground power supply is disconnected, the aircraft will naturally run out of power.

The following aircraft will definitely not disconnect the ground power without authorization, as long as they also take into account the pilot's report. Zhang Qijun figured out what was going on in a flash.

"This." Zhang Qijun scolded in his heart, stood up slightly, and looked out. Because the interface of the ground power supply is on the right side, that is, Xu Qing's side, the ground power supply car is also on Xu Qing's side, and Zhang Qijun needs to stand up slightly to see it.

As soon as Zhang Qijun looked at the ground power truck, he saw that there was a person who was surrounding the ground power truck, and one of the maintenance personnel found that the captain was watching them, and immediately ran to the side window of the captain.

Zhang Qijun: "What's going on?" The power is out! ”

Zhang Qijun's tone was slightly angry, originally the plane did not have air conditioning, and the passengers had great opinions on this, but now the power was suddenly cut off, and the passengers were afraid that they would doubt the safety of the plane.

Hearing the unkindness in the captain's tone, the maintenance was a little embarrassed: "There seems to be a problem with the output of electricity." ”

Just now, Zhang Qijun saw a group of people gathered next to the ground power supply truck, and he knew that there must be a problem with the ground power supply truck, and he also had to say that the maintenance of the machine? ”

The electricity used in the 737 aircraft needs to meet certain standards, and not all kinds of power sources can supply power to the aircraft. The power output of the maintenance is problematic, which means that the power output of the ground power supply vehicle does not meet the requirements of the aircraft, so it cannot be connected, even if the ground power supply vehicle is still running.

"You can't do it!" Zhang Qijun complained casually, there are really few things that go well today.

The maintenance was suddenly unhappy, which estimated his dignity as a man, and immediately retorted: "We must be able to do it, but we can't stand the power supply car, and it's not me who generates electricity, if we can generate electricity, ensure that the voltage is stable." ”

Zhang Qijun was stunned by the maintenance, this mouth is so poor that there is no one, is the maintenance of W City Airport so "able to speak"?

Thinking that it was really rude to ask a man if he was okay just now, he didn't care about the poor mouth of the aircraft attendant, and waved his hand impatiently: "Forget it, hurry up and get it done, our company is about to be scolded by passengers." ”

"It's okay, it's okay, they'll get it again, and it'll be fine in a while. Captain, don't worry! The maintenance was still persuading Zhang Qijun to rest assured, coupled with a bright smile and a full optimistic family.

Xu is really not a big deal, this machine maintenance looks like the old god is there, but his mouth is chattering: "Our ground power supply car has not been used for a long time, otherwise how can there be voltage instability, accidents." However, your luck is too bad, and you only know that the APU is broken when you stop at a remote position, what kind of luck is this! ”

Normal airlines know that there is a problem with the APU of the aircraft, and will try their best to arrange a bridge location, so that the power supply and air conditioning of the bridge are very convenient.

Ouch! Will you taunt in reverse?

Zhang Qijun really served these machines, and the machine maintenance in his hometown was dragged one by one, and the machine maintenance here was poor, is it really impossible for one side to raise one side of the people?

Zhang Qijun had a pain in his head when talking to this aircraft attendant, and made a gesture to the aircraft attendant to let him get busy by himself, retracted into the cockpit by himself, and poured a sip of water violently, it was too hot to talk to these poor-mouthed people.

"How?" Xu Qing saw that Zhang Qijun's negotiation was completed and asked with concern.

Zhang Qijun replied weakly: "It's just a broken machine, the voltage is unstable, they should be able to pinch it." ”

"Hurry up and leave, I really can't stand it here." Zhang Qijun also added.

Xu Qing was confused by Zhang Qijun's words, but the green tendons on Zhang Qijun's head showed that his mood didn't seem to be so good.

Xu Qing didn't want to touch Zhang Qijun's moldy head, so he simply shut up and stopped talking, but the noise in the cabin behind him became louder and louder, and Zhang Qijun's face became colder and colder.

It's no wonder that the passenger shouted, if he is a person who doesn't understand airplanes, and sees that a plane doesn't even have air conditioning, and he comes to cut off the power with one hand, it's a bit unacceptable.

Zhang Qijun estimated that it was too fierce to see the trouble behind, in case someone suddenly decided to terminate the trip at this time, then they were afraid that they would not be able to catch up with the take-off time, so they directly made a passenger broadcast.

This broadcast is not long, the main thing is to apologize for the failure of the air conditioner, and then throw all the power outages to the airport, of course, it is not their responsibility, this pot is originally the airport to bear.

In the end, Zhang Qijun also said that the plane was about to be pushed away, and asked the passengers to return to their original positions.

I have to say that the captain's words are still better than the flight attendants, and the news that it will take off soon is interrupted, the passengers who were originally shouting suddenly stopped a lot, and the shouts of the passengers in the cockpit were also much quieter.

Not long after Zhang Qijun finished the passenger broadcast, the ground power supply available lights were back on, Zhang Qijun took advantage of the situation to connect, and at this time the release notice came down: "Xingfei 8342, you can launch and drive!" ”

Xu Qing looked at the time, it was a little earlier than expected, and hurriedly replied: "Our APU has a problem, please start it on the spot first." ”

"You can start it on the spot, and it's good to start!"

"Start on the spot, start and get started! Xingfei 8342! ”

When Xu Qing was talking to Fang Xing, Zhang Qijun contacted the purser through the internal phone: "Okay?" ”

"That's it!"

Zhang Qijun hurriedly ordered: "Hurry up and close the hatch, you can go!" ”

"Okay, okay!" The purser didn't expect the take-off time to be a little earlier, so he was happy and quickly closed the cabin door, and at the same time asked some flight attendants who were still dealing with baggage problems to move faster.

When the front hatch was closed, Xu Qing hurriedly turned on the anti-collision light, turned on the fuel pump, turned off the A hydraulic system, and began to make a pre-start checklist. Although the time was tight, the order was not wrong, and the pre-start checklist needed to be done before starting the engine.

Although Zhang Qijun was in a hurry to leave, the rules were still in a hurry, so he endured his temperament and obediently made the pre-start checklist.

When Xu Qing turned on the anti-collision lights, the maintenance staff received the information, but they knew that they needed to start on the spot first, so they did not rush to hang the trailer, but beckoned the ground air source truck to come over.

When the pre-start checklist was just completed, the maintenance took the lead in contacting the cockpit.

"Captain, the ground air source car is ready, and it can start at any time." Said the maintenance officer.

Zhang Qijun saw that the pre-start checklist was completed, and hurriedly replied: "Then start a shot." ”

Xu Qing confirmed that the APU bleed air valve was in the closed position, and at the same time confirmed that after the pipeline pressure rose, he started the No. 1 engine first according to the normal starting procedure.

At this time, the aircraft uses the electricity of the ground power supply vehicle and the pressurized air source of the ground air source vehicle, and the No. 1 engine starts normally, and after stabilization, Zhang Qijun connects the generator driven by the No. 1 engine, and the aircraft can use the No. 1 generator for power supply.

When he turned on the generator driven by an engine, Zhang Qijun licked his lips meaningfully, and happened to be seen by Xu Qing, it seems that Zhang Qijun is also under some psychological pressure. However, the problem with the fault record is the No. 2 generator, which starts the second engine after a while, and then connects to the No. 2 generator, and that is when you really need to pray.

"As soon as the engine starts normally, you can remove the power supply car and the gas source car." Zhang Qijun informed the maintenance road.

Maintenance: "I have removed the power and gas supply, and the trailer has been hung up for you." ”

Xu Qing saw that the start was normal, and immediately contacted the release: "Xingfei 8342, as soon as the start is completed, I request to launch and drive." ”

"You can launch and drive, Xingfei 8342!"