On July 22, 2020, Ethiopian Airlines (hereinafter referred to as Ethiopian Aviation), a Boeing 777 full cargo aircraft that performs international freight flights, completed the cargo loading of cargo in Shanghai Pudong Airport No. 306, and the door closure and waiting for departure. The crew found a fire alarm in the cargo cabin, and the smoke appeared on the main cargo cabin and a bright fire appeared. Then the unit announced the highest danger signal "Mayday" on the ground on the ground. After nearly three hours of rescue, this Boeing 777F full-cargo aircraft numbered ET-ARH was extinguished. The relevant news became the focus of major media attention on the same day.
On January 7, the air accident survey report obtained by the upstream journalists showed that the reason for the fire of the Ethiopian Airlines cargo is not the aircraft appliance failure of the public opinion, the fire -containing battery cargo, etc. The reason is that the spontaneous combustion of chlorine dioxide disinfection tablets loaded in the main cargo cabin caused the fire in high temperature and humid environment, which directly led to the total price of the total price of about 2.3 billion yuan in this market.
▲ Ethiopian aircraft is severely damaged
The aircraft worth 2.3 billion yuan fire before taking off
The 777-200 model launched by Boeing is the first model among the Boeing 777 family. The first machine was released in 1990. The Ethiopian Airlines B77-200LR is a long-range model of Boeing 777-200. When it was put into use in 2006, it was the longest-range passenger aircraft in the world at that time. The range reached more than 17,500 kilometers and could fly continuously for 18 hours. Based on the price of an order in Emirates and Boeing in recent years, the price of a single Boeing 777-200LR cargo aircraft is US $ 340 million, which is about RMB 2.3 billion.
On July 22, 2020, ET-ARH, Ethiopian Airlines' Boeing B777-200LR full cargo aircraft, performed a shipping position at Pudong Airport 306 after the freight flights from Brussels, Belgium to Shanghai. During the short stop of the aircraft, after completing the unloading and loading work and replacing 5 crew members, it is ready to perform the next section of ET3739 flight from Shanghai Pudong via Chongqing to the Siyababa of the capital of Ethiopia. The flight is expected to be in Beijing. Take off at 14:30 on the same day. Because of the loading of the cargo, the ET3739 flight was completed and closed the cargo cabin door at about 15 o'clock on the same day. The aircraft was loaded with 69.3 tons of goods collected from all over the country. No abnormalities occur during the loading process.
At 15:14 and 04 seconds on the same day, the danger began to appear. The ET3739 units reported the frequency of the aircraft's main cargo hold of the aircraft to the Pudong Airport in English and needed fire vehicles. At 15:19 after 5 minutes, the unit contacted the ground control again, urging the fire truck to come as soon as possible. At 15:21:32, Ethiopian Airlines ET3739 flight crew issued the highest -level call -for -rescue signal "Mayday" on the ground on Pudong Airport, saying that fire rescue was required for aircraft fires. At 15:25, the fire truck at Pudong Airport reached 306 aircraft, but no smoke or bright fire was found at the fire report site. The aircraft's left front door and the cargo compartment door were then opened. The unit also evacuated the aircraft. At 15:35, the aircraft's main cargo cabin appeared on a bright fire.
In Ethiopian Airlines, during the fire rescue of the cargo aircraft, not only did Pudong Airport's fire fighting participating in fire extinguishing rescue work, the Shanghai Fire Rescue Corps took the police, the Pudong Detachment Qinqin Headquarters, and Chuansha, Zhuqiao, Sichuan Exhibition, Golden Bridge In 20 fire stations including Longyang, 38 vehicles and more than 200 firefighters such as operations, commands, and communications are disposable for various types of operations, commands, and communication. Three hours later at 18:14, the fire was controlled at the scene.
Upstream journalists noticed that during the entire rescue period, the busy Shanghai Pudong Airport announced its closure at 16:40. It was only 18:30 in the past two hours to resume operation. 34 flight delays.
▲ Ethiopian cargo aircraft in the burning
Fire lithium batteries such as aircraft faults and other reasons are excluded
After the on -site emergency response, the Ethiopian air freight machine's fire was immediately transferred to the accident investigation. According to the authorization of the Civil Aviation Administration of China, the Eastern Bureau of the East China Bureau of Civil Aviation is responsible for the specific investigation of the matter. The survey team's on-site investigation found that the aircraft overfire area was limited to the Ethiopian Airlines B777-200LR/ET -RH machine. The upper half of the fuselage was burned and worn, and the main cargo cabin was severely burned. The structure and equipment of the lower half of the fuselage have too many cigarettes. Although the appearance remains intact, there may be heat damage. No significant overfire and smoke were seen on the fuselage area of the outer wing area, the engine area, and the landing rack area.
During the survey, the investigation team first surveyed the Boeing 777-200LR full-cargo aircraft ET-ARH. As of the incident, the cargo aircraft leaned out in September 2014 completed a total of 4286 flights and falls. The total flight time was 26740 hours. Before the flight took off, the random aircraft personnel of Ethiopia had completed a short stop inspection of the aircraft. As a result, there were no failure faults. The regular inspections completed about one month before the aircraft incident were normal. On the day of the incident, the live video surveillance of Pudong Airport showed that during the main cargo cabin fire alarm to the main cargo cabin door, there was no smoke overflowing from the fuselage related components. The crew also reported that no other warning or failure information was found except the smoke alarm, and the suspicion of spontaneous combustion caused by the aircraft's own failure was excluded.
Upstream journalists noticed that in recent years, there have been many lithium batteries at home and abroad that causes fire alarms in the aircraft. After the Ethiopian air fire incident, some public opinion questioned whether it was because the cargo aircraft containing lithium batteries carried spontaneously combust the cargo cargo that had spontaneous combustion. Essence When investigating the loading of the cargo in the investigation team, the information of the freight warehouse receipt shows that there are nearly 70 tons of goods on the Ethiopian air -starting passenger aircraft, which mainly loads epidemic prevention materials such as masks, thermometers, and protective clothing. Among them, 4 votes contain lithium battery electronic products. There is no application for other dangerous goods.
The investigation team found that 4 votes contain lithium batteries. After the on -site investigation, the 50 mesh -type atomizers and the 15th sea letter receiving machines found at the scene were consistent with the name, quantity and location of the transportation order. The staff also found that the mesh -type atomizer was basically intact after inspection of each device, and only some of the outer packaging plastic boxes were melted; only 2 of the 15th sea letter receiving machines were severe, and the metal shell was dismantled. The discoloration is light and inside, and the internal circuit board is basically intact. Lithium battery -related items and other items are confirmed to be caused by external fires. Lithium batteries caught fire caused by the spontaneous combustion of the aircraft.
The eyes of the investigation team returned to the scene again. First of all, the problem that needed to be solved was the determination of the aircraft fire position. On -site exploration shows that the cargo of the PR position of the main cargo compartment of the aircraft is the most serious. The structure corresponding to the body shells corresponding to the position of the position is the lowest. Essence Investigators combined with the earliest faulty areas displayed by the earliest color change parts and cargo cabin smoke detection controllers, the investigators comprehensively determined that the fire point was located at the PR position on the right side of the main cargo cabin.
The investigation team further investigated found that the goods loaded in the PR position include a total of 6 votes. The goods recorded in the shipping order include the antibody detection kit, the collection machine containing lithium batteries, the nano -mild release and cleaning materials containing chlorine oxide Flower tea and so on. After excluding the suspicion of the lithium battery receipt machine, it has become the focus of the survey.
Where does the chlorine nano -nano -release material come from?
▲ The report believes that the biggest fire is the spontaneous combustion of chlorine dioxide products
The materials obtained by the upstream journalist show that the cargo containing chlorine dioxide is purchased and consigned by Xu from Xu in Zhejiang. The goods are mainly used for epidemic prevention and disinfection. On June 22, 2020, the owner Xu signed the domestic supplier and signed the chlorine dioxide disinfection machine and the "disinfection shield" of the "disinfection shield" containing chlorine dioxide, and then entrusted others to pay the payment. The method is sent to the consignee. Aviation cargo transportation statistics show that there are 96 boxes of cargo involving chlorine dioxide, including a total of 10,000 small bags of disinfection powder and 100 bags of chlorine dioxide disinfection tablets.
The cargo appraisal certificate made by the Shanghai Chemical Research Institute provided by the cargo owner shows that the nano -most -release materials involved (including 1%chlorine dioxide adsorbed on the nanomal material) were "non -restricted goods", nano -mitigation and cleaning materials (powder lattice Granules) are "dangerous goods", and the risk is "oxidant (main), corrosive (times)".
After the investigation team confirmed the information of the fire, the fire point and other information, the exclusion method surveyed the human destruction, the fire type, the lithium battery fire, the aircraft electrical fire, etc. In the status, the goods loaded on the fire point were investigated, and the suspicious goods were verified, and the fire was determined to be a chlorine disinfection tablets.
Why does the chlorine dioxide used for epidemic prevention and disinfection caught fire in the aircraft cargo compartment? Investigators found that the meteorological data of Pudong Airport showed that the temperature in Shanghai on the day of the incident was up to 34 degrees, and the open -air stacking method was generally used in domestic air cargo stations. The chlorine dioxide disinfection tablets found at the fire point PR cargo panels are dangerous for spontaneous combustion under high temperature and moisture.
The root simulation experiments conducted by investigators confirmed that under the weather conditions similar to the day of the incident on July 22, 2020, the temperature inside the stack was much higher than the ambient temperature, and the phenomenon of knotting will appear on the inside of the film. At the same time, because the heat dissipation was unfavorable, With sufficient conditions for spontaneous combustion. The investigation team judged that the biggest possibility of the fire on the ground on the ground was due to the spontaneous combustion of the chlorine dioxide disinfection tablets of the airborne.
▲ Simulation experiments have confirmed that the internal temperature of the goods stacked in the open -air can reach 80 degrees Celsius
Logistics consignment and concealment many factors superimposed and eventually causing a big disaster
Upstream news reporters found that the spontaneous combustion of chlorine dioxide on the Ethiopian air cargo was identified by professional institutions as "dangerous goods" before consignment, but why did it be free to send it to the plane?
The survey shows that during the consignment process, the goods provided by the cargo owner to the consignment unit Zhejiang Jetong were called "Smart Spray Machine, Chlorotharics Disinfection Shield, Chloride Disinfection Origin, Packaging Bags and Sealing Machines". The chemicals contained in this ticket have two appraisal certificates, and the appraisal conclusions are "non -restricted goods" and "dangerous goods". After communicating with the owner of the cargo owner, Jettong decided to use the appraisal conclusion as the conclusion as the conclusion as the identification conclusion. The sample name of "Non -restricted goods" "nano -mitter -release cleaning material (including 1%chlorine dioxide adsorb on nano -material)" carried out follow -up commission business, only declared the goods named "nano -mittering cleaning materials (including 1%1%, including 1% "Chlorine dioxide is adsorbed on nanomaterials)", and did not realize the actual dangerous product disinfection powder and chlorine disinfection tablets in the cargo. "The behavior was suspected of concealing the name of the goods and checked the dangerous goods by non -dangerous goods. "
The investigation team further discovered that the maximum possible spontaneous combustion and chlorine dioxide products were performed in a security inspection two days before the incident, and the security inspection personnel were paying attention to the granular substances of suspected chemicals in the goods, and accordingly, the boxer was also opened to the boxer. A instructions are issued to check the chemical transportation documents. The out -of -the -box security inspection personnel then checked the outer packaging of the goods and the transportation documents, and confirmed that the name of the goods was consistent with the transportation documents. After checking the crickets, images, and transportation files, the security inspection personnel were released on the box of the goods.
Regarding whether the work of Pudong Airport's freight security inspection involves illegal regulations, the investigation team checked the image containing the chlorine oxide cargo through the X -ray machine. The image shows that related suspicious areas and the nano -mitter -release cleaning material "Appraisal of Cargo Transportation Conditions" "Sample appearance appearance appearance" sample appearance appearance "The granularity described by the column is in line with the operation of the airport's cargo security inspection.
After a complete and detailed work, the investigation team found that the most likely cause of the Ethiopian Boeing 777 Pudong Airport Fire accident was that the chlorine dioxide disinfection tablets loaded in the main cargo cabin spontaneously ignited in high temperature and humid environments, causing fires. There are no disaster consequences such as the explosion of fuel tank, disintegration of aircraft, and casualties. In addition, there are also Pudong Airport's apron control staff in the incident that did not accurately and complete the emergency state, cargo cabin fire, etc., and the Ethiopian aviation units did not follow the handbook door and did not perform emergency evacuation emotions. Risk risk hazards.
According to the relevant conclusions, the investigation report is recommended to further study and refine the conditions for aviation transportation conditions for chlorine dioxide disinfection supplies for different contents. It is recommended that Pudong Airport further strengthen the training of standard terms in the process of information transmission to ensure accurate and smooth emergency handling information. For Ethiopia Airlines, the investigation report recommends that the company improves the emergency response capabilities to ensure that the flight unit operating manual and the company's operating manuals can be completed correctly.
The upstream news learned that the Civil Aviation Administration and Ethiopian Airlines had not disclosed relevant information on the Civil Aviation Administration and Ethiopian aviation in response to the loss of the loss of the loss of Ethiopian Aviation Boeing 777 cargo aircraft.