Why do you need to turn off your mobile phone when flying?

Question 1: Do I have to turn off my mobile phone when flying? Why? Never use portable electronic devices such as mobile phones on airplanes?

In recent years, with the increasing popularity of portable electronic devices, especially mobile phones, the use of mobile phones and other electronic devices on civil aircraft has also increased, posing a threat to flight safety. A large amount of evidence shows that the use of portable electronic devices such as mobile phones on aircraft will produce electromagnetic interference, causing aircraft navigation equipment and autopilot systems to malfunction, thereby seriously endangering aviation safety. Especially during the take-off, climb, approach and landing stages of aircraft radio navigation and communication systems, since the aircraft is at a low altitude, any electromagnetic interference may cause aircraft crashes and fatalities. This issue has attracted widespread attention from all walks of life. In 1991, shortly after taking off from Bangkok, a British airline's Boeing 767-300 aircraft suddenly activated its thrust reverser on a computer, causing the aircraft to crash and killing all 233 people on board. The investigation results showed that a laptop computer, camcorder or mobile phone directly caused this serious air crash, because the most likely cause of the sudden loss of control of the computer on board was that the aircraft was subject to severe electronic interference. The air crashes in Brazil in 1996 and in Taiwan in 1998 were also related to the use of mobile phones. In addition, there are also some situations that do not cause serious accidents but are close to the edge of accidents. On July 11, 1999, when a flight was preparing to land at Guangzhou Baiyun Airport, its track deviated by about 8 degrees. After the captain discovered this situation, he immediately notified the flight attendant to check the cabin and found that there were 4 or 5 passengers. Using a mobile phone. After the flight attendant stepped forward to stop it, the plane returned to its normal trajectory before landing. On January 8, 2000, shortly after a flight took off from Zhanjiang Airport, the captain suddenly discovered that there was a serious deviation between the aircraft compass indication and the aircraft route. The computer system showed that the aircraft deviated by 10 nautical miles. The captain immediately notified the flight attendant to conduct a check and found that a passenger was using a mobile phone. On February 13, 2000, during the approach of a flight to Zhengzhou Airport, the navigation signal was abnormal due to passengers using mobile phones on board, and the flight was unable to land normally. The flight crew stopped the flight before landing. The consequences of the above-mentioned dangerous situations would have been disastrous if the crew had not been experienced and handled them properly. So how can portable electronic devices such as mobile phones interfere with navigation systems? Devices that can cause electromagnetic interference to navigation systems include active and non-active signal transmitting devices, of which active signal transmitting devices, such as mobile phones, have a significant impact. According to international conventions, the current navigation system channels are 1200 MHz, 110 MHz, and 75 MHz, and other generators are not allowed to use these channels. However, the current channels of mobile phones, such as the GSM system is 800 MHz, the CDMA system is 900-1000 MHz, and the PCS system is 1800 MHz, which are very close to the navigation system. Once the mobile phone frequency changes, it is very dangerous to use the same frequency as the electronic equipment on board. Other non-active signal-emitting devices such as laptop computers, electronic game consoles, cameras, and tape recorders can also cause interference due to the use of high-frequency clock oscillators. In addition, for laser discs and CD-ROM devices, when the laser sensor reads information from the disc, it will generate a short voltage pulse, which is enough to interfere with the electronic system under the cabin floor. Furthermore, even if the electromagnetic interference signal is very weak, if the user sits at the front of the aircraft or there is nothing blocking it in front, it will directly affect the navigation system. Internationally, civil aviation authorities and airlines in many countries, including the United States, Canada, the European Joint Aviation Authority, and New Zealand, have successively formulated relevant regulations and procedures on restricting the use of portable electronic devices. The Civil Aviation Administration of China has also formulated relevant regulations, requiring airlines to broadcast reminders to passengers to turn off their mobile phones before taking off. However, there are still some passengers who lack safety awareness and legal concepts and are indifferent to the crew's broadcasts. They intentionally or unintentionally cause many dangers, some of which are close to the edge of accidents, seriously endangering the safety of other people's lives and property.

To this end, the Civil Aviation Administration of China has begun to formulate regulations on restricting the use of portable electronic devices such as mobile phones on aircraft, based on international practices and my country's actual conditions. This regulation will be reported to the State Council as an administrative regulation for issuance and implementation. The new regulations increase the intensity of penalties on the basis of further improving the legislation. According to Article 88 of the "People's Republic of China and Civil Aviation Law": "Radio stations and other instruments and devices used by any unit or individual must not interfere with civil aviation...gt;gt ;

Question 2: Why should you turn off your mobile phone before taking off? Navigation systems flying at high altitudes.

1. Scientific evidence also shows that using mobile phones on board is indeed potentially dangerous. The greater the difference between the frequency of electrical appliances and the frequency of some aircraft, the smaller the interference caused. to the lowest point, or completely uninterrupted. In addition to the intensity of the electrical signals transmitted by mobile phones, computers, radios, etc., which will affect the aircraft, if the frequency they transmit happens to be the same or similar to the frequency of the aircraft, plus the amplitude (or amplitude), It will cause the greatest damage and lead to dangerous situations.

2. On the aircraft, mobile phones in use will interfere with the aircraft's communication, navigation, and control systems, which is a killer that threatens the safety of the entire aircraft. During the flight, the aircraft has used airborne radio navigation equipment to maintain real-time contact with the ground navigation station to control the flight route. When visibility is low, the instrument landing system needs to be activated for landing, that is, the blind landing platform on the runway is used to guide the aircraft. The mobile phone emits electromagnetic wave signals to determine the runway location. The mobile phone not only emits electromagnetic wave signals during the call or answer process, but also continuously contacts the ground base station during its search process. The time is very short, but it has strong continuity, so the electromagnetic waves emitted by mobile phones will cause interference to the aircraft navigation system.

Question 3: Why should you turn off your mobile phone before taking off? Mobile phones are used to ensure a smooth flight and the safety of the aircraft and passengers.

When used, mobile phones will produce electromagnetic waves. Such signals may affect the sensitive computers and navigation systems on the aircraft, disrupting the normal operation of the flight system. Work is a threat to flight safety, especially when taking off, climbing and landing. At this time, the mobile phone will search for signals after being turned on. Not only will it emit electromagnetic wave signals during the process of making or receiving calls, but it will also continuously communicate with the ground in standby mode. Base station contact. During the search process, although the time of each signal transmission is very short, it has strong continuity. The frequency used by the mobile phone and the electromagnetic wave frequency used by the aircraft to contact the tower may be similar or even superimposed. It is regarded as a command signal from the tower, causing misoperation. In addition, when visibility is low, the aircraft needs to activate the instrument landing system to land, which means using the blind landing platform on the runway to transmit electromagnetic wave signals to the aircraft to determine the runway location. . The electromagnetic waves emitted by mobile phones are likely to cause interference to the aircraft’s signal receiving system.

Therefore, for safety reasons, it is better to turn off the phone on the aircraft.

Problem. Four: Is it necessary to turn off the mobile phone when flying? Yes, it is the best choice for passengers to turn off the mobile phone during the entire flight

The flight mode of the mobile phone means that the communication module of the mobile phone is turned off. You cannot make calls or send text messages, and there is no signal with the base station. Contact, you can use other functions such as calculator, stopwatch, clock, etc. at this time. This is an "anti-interference" state, and it is also the original meaning of "airplane mode". It means that the mobile phone will not interfere with it like flying on an airplane, but it does not mean that the mobile phone will not interfere with the takeoff and landing of the plane. The mobile phones currently used by people use frequency hopping pulses to transmit signals, and there will be a certain amount of electromagnetic radiation, so many secondary waves of different frequencies will be generated.

Although these secondary radio waves are very weak, airborne communication equipment is very sensitive, and the flight mode effect of most mobile phones is not stable. Therefore, in the absence of certainty whether there is obvious harm, in order to protect the hundreds of people on board, From the starting point of being responsible for the safety of passengers, it is the best choice for passengers to turn off their mobile phones during the entire flight.

Question 5: When do you need to turn off your mobile phone on an airplane? The person upstairs is wrong

In fact, mobile phones have no impact on the aircraft at all now, and it was the same in the past.

I am a student pilot of Air China, and the instructor was the instructor when we were on the training plane. Sometimes I bring my mobile phone with me, but it has nothing to do with it. So far, no laboratory can prove that mobile phones can affect any electronic equipment used in flying.

However, safety is the first priority in civil aviation. In order to be foolproof, I would rather choose It is prohibited to use mobile phones and anything else that emits electromagnetic waves.

Many airlines have already planned to allow the free use of mobile phones during flights.

In addition, although it is not allowed to use mobile phones during flights, It will affect flight, but it will also affect ground mobile base stations. Because of the fast flight speed, mobile phones will switch between different base stations at high speed, which will affect billing and even cause the device to crash. Compared with affecting airborne equipment, this impact is more practical. Of course, At around cruising altitude (11000), it is impossible for ordinary mobile phones to have a signal, so they cannot be used even if they are turned on.

Question 6: Why do you need to turn off your mobile phone when flying? The mobile phone network will affect the aircraft radio system.

Question 7: Why should you turn off your mobile phone when flying? Hello friends, because the aircraft communicates with the tower through radio during flight. If you turn on your mobile phone, the signals received and emitted by the mobile phone will interfere with and affect the normal flight of the aircraft. You must know that mobile phones are also radio emission sources

Question 8: Why do mobile phones need to be turned off when flying? Under the current circumstances, in order to prevent the radio waves emitted by passengers’ wireless devices from interfering with the operation of the aircraft, relevant authorities stipulate that users must turn off mobile phones and other devices when flying.

In fact, it is only the radio waves emitted by users' wireless devices that may cause interference to aircraft flights, while other functions such as games will not actually have any adverse effects. The project set up by the Consumer Electronics Association on the 2nd U.S. time is to develop a simple method to determine that the radio transmission function of a user's device has been disabled, so that users can continue to use their mobile phones without affecting aircraft flight. Other functions.

Question 9: Why should you turn off your mobile phone on an airplane? 1. Reasons why you cannot use your mobile phone:

The radio waves emitted by mobile phones may also cause explosions or affect the operation of passenger planes at 9500 A navigation system that flies at an altitude of one meter.

1. Scientific evidence also shows that using mobile phones on board is indeed potentially dangerous. The greater the difference between the frequency of electrical appliances and the frequency of some aircraft, the interference caused will be minimized or not interfered at all. In addition to the intensity of the electrical signals transmitted by mobile phones, computers, radios, etc., which will affect the aircraft, if the frequency they transmit happens to be the same or similar to the frequency of the aircraft, plus the amplitude (or amplitude), it will cause maximum damage and dangerous situations. situation.

2. On an airplane, mobile phones in use will interfere with the aircraft’s communication, navigation, and control systems, which is a killer that threatens flight safety. Throughout the flight, the aircraft used airborne radio navigation equipment to maintain real-time contact with the ground navigation station and control the flight route. When visibility is low, the instrument landing system needs to be activated for landing, that is, the blind landing platform on the runway is used to transmit electromagnetic wave signals to the aircraft to determine the runway position. The mobile phone not only emits electromagnetic wave signals during the process of making or receiving calls, but also constantly contacts the ground base station in standby mode. During its search process, although the time of each signal transmission is very short, it has strong continuity. Therefore, the electromagnetic waves emitted by mobile phones will cause interference to the aircraft navigation system.

2. The prohibition of using mobile phones on airplanes has become a thing of the past:

1. Since 2000, the dream of using mobile phones on airplanes has been realized. In the UK, Virgin Airlines Passengers on a flight from Shanghai to London became the first to be allowed to use their mobile phones to make calls during the flight, a first for a global airline.

This latest in-flight phone service The technology is equipped with an on-board mobile communication system developed by British Telecom. This system allows passengers to make mobile phone calls freely on the aircraft, and the call charges will be automatically transferred to the user's Global Mobile account. Passengers only need to make phone calls after boarding the plane. The SIM card is placed on the mobile phone specially provided on the aircraft, and the registration number can be entered to communicate freely.

2. People's Daily Online-Jiangnan Times, August 14, 2004: China Mobile and China Unicom are two major operators The "level" of the Shang Zhizhi is rising higher and higher, from the ground to the sky! China Unicom was the first to reveal that it will soon launch commercial CDMA wireless phone services in the air, and the inability to use mobile phones on airplanes will become a thing of the past.

According to the relevant person in charge of China Unicom, to achieve the purpose of using mobile phones on airplanes, one only needs to install a built-in CDMA base station on the airplane. The base station can use communication satellites to achieve contact with the ground, and then Access to global terrestrial CDMA networks. Once this device is installed on the aircraft, passengers can freely use their mobile phones to make calls or send short messages during the flight.