The highly anticipated domestic aircraft C919 has once again ushered in a landmark event. According to Xinhua News Agency, on September 28th, China Eastern Airlines, the global first user of the domestically produced large passenger aircraft C919, signed a purchase agreement with COMAC again in 2021, adding 100 aircraft to the first batch of 5 C919 aircraft. This is the largest single order for C919. China Eastern Airlines, as the world's largest user of the C919, has fully launched large-scale commercial operations of domestic large passenger aircraft and large fleets. Regarding this, Hong Yong, Associate Researcher at the E-commerce Institute of the Research Institute of the Ministry of Commerce, stated: This is an important milestone in the development of domestic civil aircraft manufacturing industry, and also another successful practice of COMAC's self-developed C919 large passenger aircraft entering the market. This fully demonstrates that domestic civil aircraft meet market demand, have received market recognition and customer trust, and also proves that domestic large aircraft have good competitiveness. This is beneficial for promoting the development of China's civil aviation industry and improving the core competitiveness of China's manufacturing industry The significance is significant With the continuous delivery of orders, the C919 large aircraft will carry more and more passengers to further destinations. Professor Zou Jianjun from China Civil Aviation Management Cadre College said, "After mass production and delivery, the C919 large passenger aircraft will inevitably embark on a path of large-scale operation, and the domestic capacity supply of the C919 will gradually expand." In the future, delivery is expected to accelerate. Apart from China Eastern Airlines, other large airlines also hold a positive attitude towards the C919 large passenger aircraft. At the annual report performance briefing held by the listed airline earlier, Air China stated that in 2010, the company signed a purchase agreement with COMAC for 20 C919 aircraft and continued to monitor the progress of the C919. China Southern Airlines also stated that it maintains a high level of attention to the C919 aircraft, maintains close communication with COMAC, and will proceed with subsequent work in accordance with relevant procedures. From the delivery situation, COMAC has already delivered two C919 large passenger aircraft. According to the aforementioned purchase agreement, the C919 aircraft purchased by China Eastern Airlines will be delivered in batches from 2024 to 2031. Among them, 5 aircraft are planned to be delivered in 2024, 10 aircraft are planned to be delivered annually from 2025 to 2027, 15 aircraft are planned to be delivered annually from 2028 to 2030, and 20 aircraft are planned to be delivered in 2031. From the perspective of international precedent, the early delivery of any new aircraft is relatively slow. In the future, the delivery of C919 large aircraft is expected to accelerate. As the flight routes of C919 aircraft gradually increase, more passengers will be able to travel on the C919 aircraft. "Qi Qi, an expert at the China Civil Aviation High Quality Development Research Center, told reporters. Qi Qi believes that the current coordination of the large aircraft industry chain can support the sustained or even accelerated delivery of C919 aircraft. However, it should be noted that there is currently a high demand for improving the localization rate of the large aircraft industry chain, and there is still uncertainty about the cooperation of foreign suppliers. Domestic suppliers still need to further increase their technological innovation. The market prospects are broad. Currently, COMAC is developing in the direction expected by the industry. On the one hand, the landing of the largest single order means that COMAC is expanding its market share, and the gradual acceleration of delivery speed also means that