中国民用航空局3月20日发布《关于“3·21”东航MU5735航空器飞行事故调查进展情况的通报》。通报显示，由于本起事故非常复杂、极为罕见，调查还在持续深入进行中。
The Civil Aviation Administration of China (CAAC) said Monday that its investigation into flight MU5735 that crashed a year ago is still in progress as the case is "very complex and extremely rare."
通报说，2022年3月21日，东方航空云南有限公司波音737-800型客机（注册号B-1791），执行MU5735昆明长水机场至广州白云机场国内定期客运航班。13时16分飞机从昆明长水机场起飞，64分钟后偏离巡航高度8900米快速下降，坠毁于广西壮族自治区梧州市藤县埌南镇莫埌村附近。机上123名旅客、9名机组成员全部遇难。
The China Eastern Airlines Boeing 737 aircraft, which departed from Kunming in Yunnan province bound for Guangzhou in Guangdong province, crashed into a mountainous area near the village of Molang in Tengxian, in the county of Wuzhou, in South China's Guangxi Zhuang autonomous region on March 21, 2022. All 123 passengers and nine crew members died in the crash.
中国民用航空局依据中国民航规章《民用航空器事件技术调查规定》（CCAR-395）和《国际民用航空公约》附件13《航空器事故和事故征候调查》的有关规定，会同有关部门对事故开展了深入、细致、严谨的技术调查工作。
In the past year, the CAAC has strictly followed related regulations and conducted an in-depth, meticulous and rigorous investigation into the accident along with related departments.
一年来，技术调查组对飞机残骸进行详细检查，确定坠地前飞机关键操纵部件可能的工作状态，对100余件重要残骸进行实验，分析损坏原因；对机组成员的资质能力、航班运行、飞机适航维修、航空公司组织管理等情况开展调查；对空中交通管制服务，机场地面保障，旅客、行李、货邮的安检和装载，危险品载运等情况开展调查；结合相关数据对飞机最后阶段飞行状态进行分析，使用飞行模拟机和真机开展模拟验证。
Over the past year, the technical investigation team conducted a detailed inspection of the aircraft wreckage to determine the possible working state of the aircraft's key control components before the crash, and carried out experiments on more than 100 important pieces of debris to analyze the causes of damage. The team also carried out inspections into the qualifications and abilities of crew members, flight operation, airworthiness maintenance of aircraft, as well as the airline company's management. Other investigations have also been carried out including air traffic control services, airport ground support, and the security check of passengers, luggage and cargoes. Combined with the relevant data, the flight state of the aircraft in the final stage was analyzed, and the flight simulator and real aircraft were used for simulation and verification.
截至目前，技术调查组开展了现场勘查、资料检查、人员访谈、实验分析等大量工作，但由于本起事故非常复杂、极为罕见，调查还在持续深入进行中。后续，技术调查组将在前期工作基础上继续开展原因分析及实验验证等工作，并根据调查进展情况及时发布相关信息。
However, due to the complexity of the accident, investigation work must continue. The investigation team will continue to carry out cause analysis and experimental verification based on the previous work, and timely release relevant information according to the progress of the investigation, the administration said.
相关通报引发公众广泛关注，新华社记者就相关问题采访了南京航空航天大学民航学院副院长邵荃和中航技进出口有限责任公司客户服务部训练与飞安办主任高俊，以下为采访节选：
为何在此时发布此次调查进展情况通报
南京航空航天大学民航学院副院长邵荃：
运输航空事故往往社会影响大，公众关注度高。在事发周年向公众披露有关调查进展信息是国际民航业界的通行要求和做法。
一般来说，大型运输航空事故调查的周期往往都超过一年，这主要是由于调查所面临的技术复杂性和不确定性，很多技术疑点、难点都需要反复论证，一些关键结论还需要得到工程实验的验证支撑，这都要耗费大量时间。统计表明，过去30年全球民航所发生的千余起商业航空事故中，在一年内发布最终报告的仅占25%。因此，国际民航组织对于航空器事故调查报告的公布时限做出了原则性和灵活性相结合的制度安排，我国民航规章在这方面与国际规则保持了一致性。
从历史上看，法航AF447、埃塞航B737MAX等事故在该阶段都发布过中期报告或中期声明，对调查进展情况进行介绍，回应遇难者家属及社会关切。
Disclosing information on the progress of an investigation to the public at the one-year mark is a common practice and requirement in the international civil aviation industry, Shao Quan, a professor at the Nanjing University of Aeronautics and Astronautics, told Xinhua.
Investigations into large aircraft crashes generally last more than a year as they face technical complexities and uncertainties, and many doubts and technical difficulties need to be repeatedly scrutinized, which is time-consuming, Shao said, explaining why the investigation is not yet complete.
Over the past 30 years, only 25 percent of civil aviation aircraft accident investigations in the world published final reports within a year, Shao added.
如何理解“本起事故非常复杂、极为罕见”
中航技进出口有限责任公司客户服务部训练与飞安办主任高俊：
航空器事故调查是一项复杂的系统工程，通常需要从人员资质及操作、航空器适航状态、天气环境、地面保障、空管指挥、公司组织管理等多方面开展全面深入的调查。
从目前了解的情况看，此次事故与以往存在很大差异。飞机高速坠地后几乎完全解体，残骸琐碎且分布较散，这都极大增加了现场搜寻勘查和残骸取证工作的难度。按照事故调查程序，调查组需要对所有寻获的残骸进行辨识，对重要残骸进行详细检查和实验分析，以便确定失效机理和最后阶段的工作状态，为后续调查分析提供证据，这些都是非常复杂专业的工作。还有通报中所提及的对飞机适航维修等情况开展调查，一般来讲，这个调查工作量也很大，需要调查飞机全生命周期的适航维修情况，如航线和定检、各类修理改装、适航指令及服务通告执行等工作记录，涉及的资料可能达成千上万份，需要耗费大量人力和时间，这些都反映出本次调查工作的技术复杂性。当然，除了残骸分析验证和飞机适航维修调查，事故调查涉及的其他方方面面同样纷繁复杂，都需要调查组严谨细致、客观深入地开展工作，确保最终调查结论经得起历史检验。
Gao Jun, an official of the China National Aero-Technology Import and Export Corporation, said that investigations into aircraft crashes are complex processes, which usually require inspections of the qualifications and abilities of crew members, their operations, the airworthiness status of aircraft, weather conditions and airline management, among others.
Judging from what we currently know, the case is quite different from any seen in the past, as the aircraft almost completely disintegrated after falling to the ground at a high speed and the wreckage was scattered, which greatly increased the difficulty of on-site search and remains collection work and added to technical complexities, Gao said.
综合来源：新华网，中国日报网，民航局网站
