Why does Malaysia Airlines lose contact depends on the answer?

Why did the passenger plane lose contact?

(1) The loss of Malaysia Airlines Flight MH370 and the global search action it triggered attracted worldwide attention and touched people's hearts. Under the condition of modern science and technology, why did an advanced passenger opportunity suddenly lose contact? To understand why, we should start with how the plane keeps in touch with the ground.

Under normal circumstances, the plane will keep in touch with the ground through various radio communication systems. Take Boeing 777 as an example. This advanced passenger plane has three independent radio communication systems to keep in touch with the ground. Among them, the high-frequency communication system is a long-distance communication system, and the communication distance can reach several Qian Qian meters. Very high frequency (VHF) communication system with short distance is most commonly used, and its operating distance is 74 kilometers at an altitude of 300 meters. Because the take-off and landing periods are the most frequent contact periods between the aircraft and the ground, and also the most prone to accidents in flight, in order to ensure the high reliability of VHF communication systems, civil aircraft are generally equipped with more than one radio communication system.

⑶ Ground control radar is also one of the ways for controllers to obtain aircraft position information. Control radar is divided into primary surveillance radar and secondary surveillance radar. The surveillance radar obtains the echo through scanning, and the small light spot displayed on the screen is the plane in the air. The secondary surveillance radar will send an interrogation pulse to the plane in the air. After receiving the interrogation pulse, the airborne transponder will compile the transponder code, altitude, speed and other information into a response pulse and send it back to the ground. The information obtained by the secondary radar is combined with the aircraft position information obtained by the primary surveillance radar, which constitutes the comprehensive information finally displayed on the ground controller terminal, and keeps in touch with the aircraft through these information.

⑶ In addition to radio communication system and ground control radar, the aircraft will also keep in touch with the ground through ACARS system. ACARS system is the most important means to monitor the flight state of aircraft on the ground, and the ground control center can know the engine, altitude, heading and other data of aircraft at any time.

5] If an airplane cannot be called by VHF radio, scanned by primary surveillance radar, answered by secondary radar, or even the ACARS system is turned off, then the airplane will completely lose its ground control system.

[6] From a technical point of view, the loss of Malaysia Airlines passenger plane is closely related to the fact that the existing air traffic control technology mainly relies on ground radar is difficult to grasp the actual position of the aircraft. ADS-B air traffic control technology, which is known as the next generation air traffic control technology, was actually developed as early as 10 years ago. The delay in popularization is not due to technical reasons, but to the need to update the ground and air equipment of all current air traffic control systems, and all air traffic control personnel and pilots need retraining. The difficulty can be imagined. I wonder if the loss of Malaysia Airlines can become a booster for the new generation of air traffic control technology to go to the foreground?

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29. What is the function of paragraph (1) of the selected text? (3 points)

30. The underlined sentence in paragraph (2) "Take Boeing 777 as an example. This advanced passenger plane has three independent radio communication systems to keep in touch with the ground. " What explanation methods are used? What is the function? (4 points)

3 1. Can the word "one" added in paragraph (3) be deleted? Why? (3 points)

Read paragraph (4) of the text and find out three ways for the plane to keep in touch with the ground. (3 points)

33. Please talk about whether the loss of Malaysia Airlines can become a booster for the emergence of a new generation of air traffic control technology in combination with the contents in paragraph [6] of the selected text. (2 points)

29. Stimulate readers' interest in reading; (1) leads to (or explains) the object of this article; (1) leads to the following explanation. ( 1)

30. Examples and figures. (2 points) Specifically and accurately explain that under normal circumstances, the aircraft will keep in touch with the ground through various radio communication systems. (2 points)

32. Radio communication system, ground control radar, ACARS system. (3 points)

33. You can speak fluently if you make sense. (2 points)

Example 1: No, because the promotion of the new generation of air traffic control technology requires all the ground and air equipment of the current air traffic control system)

3 1. cannot be deleted. (1) "one" plays a restrictive role, indicating that ground control radar is a way for controllers to obtain aircraft position information, not the only way. (1) is not practical after deletion, which reflects the scientificity, accuracy and rigor of the interpretation language. (1) update, all air traffic controllers and pilots need retraining, and the difficulty can be imagined.

Ex. 2: Yes, a new generation of air traffic control technology was developed as early as 65,438+00 years ago. Although its popularization has encountered difficulties, the loss of Malaysia Airlines will certainly arouse people's vigilance and push the new generation of air traffic control technology to the forefront.