A comprehensive review of the development of China's large aircraft

May 5, 2017, Shanghai Pudong Airport. This is one of the busiest civil aviation airports in China. On normal days, an average of one plane takes off every minute. However, today, the airport is exceptionally quiet. At 2 p.m., a passenger plane with a blue stripe on the tail and a green tail slowly taxied to the end of the runway and began to accelerate forward with the roar of two turbofan engines.

The plane that is taking off is the C919, the latest large civil airliner developed by my country. This is its maiden flight. As the plane takes off, the enthusiasm of the audience also rises. Among them, a white-haired old man in a suit and tie stands out in the crowd. The wind at the airport makes his white hair a little messy, but it does not dry the tears in his eyes. A plane flying into the sky is his dream. Looking at the fluttering silver wings, perhaps his thoughts go back to more than 70 years ago.

At that time, the planes flying in the sky were not angels carrying dreams, but demons bringing death. A young boy hid in a ditch in the field. Through the branches above his head, he saw a plane with a red sun painted on its fuselage dropping evil bombs, and the loud explosions rang out everywhere. The boy's name was Cheng Bushi. At that time, perhaps he did not expect that he would be accompanied by planes all his life, turning him into an angel carrying dreams.

An Eagle Without Wings: The Difficult Start of China's Civil Aviation Industry

During the Anti-Japanese War, since Japan had completely occupied the southeastern front, almost all the supplies for the war came from a route from India to southwest China. This route crossed the Himalayas and had to cross mountains and ridges. The route was up and down, so it was also called the Hump Route. Most of the planes flying on this route were transport planes. Unlike the planes with red suns painted on their fuselages, these planes brought hope for victory in the war of resistance. Therefore, the bigger the plane, the greater the hope.

One of the earliest profitable civil aircraft in the world was the DC-3 that flew over the Hump Route. After the end of World War II, a large number of DC-3s used in the war flooded into the civil aviation market, allowing the civil aviation industry to flourish. Airplanes shortened the distance between people and made the world smaller. Air routes are like blood vessels connecting the world, bringing new vitality to civilization on Earth.

The civil aviation of New China originated from the Two Airlines Uprising. In 1949, employees of the two largest airlines in old China, Central Airlines and China Airlines, took off from Hong Kong with 12 passenger planes, abandoned the dark and joined the construction of New China. The earliest civil aviation industry of the Republic started. Since then, more and more civil airliners have been flying over China, from piston propeller DC-3 and CV240 to turboprop Il-18 purchased from the Soviet Union, and then to the jet airliner Trident purchased from the United Kingdom. By the 1970s, China's civil aviation had more than 100 aircraft of various types, and the operation had begun to take shape. But for a big country with a land area of ​​9.6 million square kilometers and hundreds of millions of people, this scale is far from enough. One of the major constraints is the development of civil aircraft.

After World War II, Britain and the United States successively developed large jet civil airliners, with faster speeds and more comfortable cabin environments, which gave air travel a new experience. In particular, the Boeing 707 passenger aircraft developed by Boeing in the United States set the design template for modern civil airliners, so that most of the successful civil airliners after that had a similar layout. The Boeing 707 is the world's first commercially successful jet civil airliner. Commercial success means that both the manufacturer of the aircraft and the airline operating the aircraft can make money through it. To achieve this goal, the aircraft needs to be safe and economical enough. To this day, there are still many people in the world who think that flying is not safe, and an aircraft that often encounters accidents will inevitably be disliked by passengers and airlines, thus ruining his career. Economy is an essential attribute of commercial operation. Whether the cost of the aircraft itself is too high, the fuel consumption of the aircraft is too high, or the maintenance is difficult, it is difficult to succeed in business. The Boeing 707, a nearly perfect civil airliner at the time, came to China for the first time in 1972 when US President Nixon visited China as the ice-breaking of Sino-US relations.

For the first time, the Chinese people really came into contact with this advanced civil airliner. Cheng Bushi, the young man who hid in the ditch to avoid the bombing of Japanese planes, also saw this plane from the overwhelming reports. At this time, he was already the deputy chief designer of China's first jet civil airliner. Looking at this elegant and even gorgeous plane, Cheng Bushi's mood was very complicated. As an aircraft designer, it was hard not to like such a work. But such an airplane did not belong to the Chinese. In that era, Chinese leaders could only take propeller planes rented from abroad when they visited abroad. In this regard, the European media commented: "China is an eagle without wings." This makes the work in front of Cheng Bushi more important.

The dream was once within reach: the regret of Y-10 and the breakthrough of ARJ-21

Large aircraft directly reflect the overall level of a country's civil aviation industry and even the entire industrial system. Without it, China will always be looked down upon by the West.

Cheng Bushi and a group of aerospace people thought and hoped. Finally, on August 21, 1970, the state issued a document to start the development of large aircraft. The "708 Project" was officially established and the aircraft was officially named "Yun 10".

It was the third year after the Y-10 project, China's first civil jet airliner, was approved, and the general appearance of the aircraft had just been determined. The layout was based on modern civil jet airliners such as the Boeing 707. The cylindrical fuselage is more suitable for high-altitude cabin pressurization, and hanging the engine under the wing is more conducive to maintenance than hanging it on the tail like the Trident or placing it inside the fuselage like the H-6. This is more advantageous for a passenger aircraft that needs to continue commercial flights. Therefore, Chinese aviation people gave up the initial plan to transform the passenger aircraft based on the H-6 and aimed at the world's most advanced level. Who knew that this aim would take 8 years.

At that time, the largest aircraft in China was the H-6, with a wingspan of 33 meters and a maximum take-off weight of 79 tons. This aircraft was a copy of the Soviet Tu-16 bomber, and all its designs were based on evidence. The wingspan of the Y-10 is 10 meters larger than that of the H-6, and its maximum take-off weight reaches 110 tons. Without any design data reference, the difficulty can be imagined. Researchers from aviation design institutes across the country conducted research day and night, drew and distributed 143,000 pages of drawings, and finally sent my country's first jet civil airliner, the Y-10, into the sky in 1980. Subsequently, more than four years of test flights were carried out, and even 7 flights to Lhasa, Tibet, were made. During the test flights, a large amount of materials were transported to Tibet. The excellent flight performance of the Y-10 made the then president of Boeing sigh: You have graduated, and we have only graduated a few years earlier than you. Just as this large aircraft carrying the dreams of the nation's aviation people and the glory of the nation's people was proudly soaring in the blue sky, the project came to an abrupt end, the Y-10 was discontinued, and the dreams of aviation people were shattered.

Some people say that the Y-10 was cancelled because of lack of money, while others say that it was caused by Western interference. However, if we look back at the design and test flight data of the Y-10 at that time, we will find that among the problems of the project at that time, one of the most difficult was how to meet the airworthiness requirements. Airworthiness, although unfamiliar, these two words that seem easy to understand have become a shackle that binds China's civil aircraft, and this shackle has lasted for more than 20 years.

Airworthiness literally means suitable for navigation. Navigation here refers to flights on civil routes. Unlike military aircraft, civil airliners have high requirements for safety and reliability due to their large passenger capacity and frequent flights. The US military high-altitude and high-speed reconnaissance aircraft SR-71 Blackbird fell down more than one-third of the time due to reliability issues during test flights and service, but this did not prevent it from becoming a famous aircraft of the generation and going down in history because of its outstanding high-altitude and high-speed performance. However, McDonnell Douglas' DC-10 passenger aircraft had 15 accidents out of a total of less than 400 aircraft. This passenger aircraft was called the "king of air crashes" and the "cursed aircraft", while the Concorde passenger aircraft only crashed once, causing it to withdraw from the market. Civil airliners have zero tolerance for safety defects. To this end, countries with an early start in the civil aviation industry have formulated strict and detailed airworthiness standards, covering everything from the structural strength of the aircraft, engine reliability, deformation in the face of a crash, and the reaction after being hit by a bird, to the arrangement of seats, the location of emergency exits, the color of control buttons and handles, and the size of seat belts. Almost every item in the airworthiness standards is derived from accident cases in real route transportation.

SR-71 Blackbird, picture from Tuchong.com

It can be said that Western countries crashed planes, summarized their experiences, and formulated rules. Such rules are constantly being updated, becoming more and more stringent and detailed, and the entry threshold for civil aviation passenger aircraft is getting higher and higher. If we do not challenge this rule, even if the Y-10 is built, it will only be used for viewing and cannot be put into operation. Standards can be used as a reference, but whether the aircraft meets the standards requires a lot of tests and test flights. However, such work was not mature at the stage of Y-10 research and development. For example, many parameters of the Y-10 flight do not have accurate and reliable measurement methods that meet international standards. Such primitive test flight methods and technologies cannot support the development of modern passenger aircraft.

Grievances and unwillingness did not extinguish the dreams of Chinese aviation engineers. As long as there is a spring breeze and a spring rain, this dream will grow again.

In 2002, the State Council approved the development of the domestically produced regional jet ARJ21. The backbone of the Y-10 project was re-equipped and a new generation of aviation personnel who grew up in the spring breeze of reform and opening up also joined the team. The red flag was planted again, and a new battle began. This time, we directly aimed at the world's most advanced civil aircraft airworthiness standards.

Whether an aircraft is airworthy is evaluated by the civil aviation management department. In China, it is the Civil Aviation Administration of China, and in the United States, it is the Federal Aviation Administration (FAA). These departments will strictly supervise and inspect the development, production and test flight process of the aircraft. After meeting the standards, a type certificate will be issued for the aircraft. The type certificate is a symbolic document of the airworthiness of an aircraft. The FAA is almost the originator of civil aviation airworthiness certification, so it has higher effectiveness internationally. With the FAA certification, the passenger aircraft can be put into operation almost all over the world. Although the airworthiness standards of the Civil Aviation Administration of China for civil aviation passenger aircraft are derived from the FAA, there is no experience in the airworthiness certification process. For this reason, China cooperates with the United States to let the FAA supervise and review the entire process of the Civil Aviation Administration of China's review of ARJ-21, which is equivalent to inviting a referee to judge whether our own referee's judgment is accurate. This is a shadow review. If it passes, the FAA will determine that the airworthiness certification of the Civil Aviation Administration of China also meets their standards, so there is no need to review it again. The two countries recognize each other's airworthiness certification work, which is bilateral airworthiness.

ARJ-21 attempted to conduct shadow review and bilateral airworthiness, which could help it learn advanced Western airworthiness test flight technology and lay the foundation for the development of subsequent passenger aircraft. Although ARJ-21 is a relatively small regional airliner, its test flight has been full of twists and turns. It took three years from the first flight to the start of certification test flight. After entering the certification test flight, it was even more difficult. The biggest problem encountered was the lack of experience in test flight.

Practice is the only criterion for testing truth. The test and test flight of passenger aircraft is to simulate various abnormal situations that may occur in route operation under the premise of ensuring safety. As long as it is a simulation, there will be a gap with reality, and what the test personnel have to do is to minimize this gap. The airworthiness management department also supervises whether these tests can accurately represent the true reflection of the aircraft when facing these situations. For example, whether the indication of the flight speed instrument on the aircraft is accurate requires a calibrated standard measuring tool that is not affected by the airflow on the surface of the aircraft. In previous military aircraft test flights, we generally install a longer pitot tube at the front of the aircraft to measure the standard airspeed. This method can avoid the interference of the fuselage on the pitot tube when measuring small aircraft, but for large aircraft, its results may be inaccurate.

In the FAA's airworthiness test, most of the airspeed is measured by the drag cone extending from the tail. This technology is still blank in my country, and we need to start from scratch to explore and select or even design standard measuring tools. Although China and the United States have signed shadow verification and bilateral airworthiness agreements, perhaps from the beginning, the Americans never thought about letting China, the new student who had just transferred in, pass the exam. They still adopted a blockade attitude towards test flight technology. I will supervise the exam, but you have to solve the review materials yourself. In this way, from the establishment of the project in 2002 to the acquisition of the type certificate from the Civil Aviation Administration of China in 2014, in 12 years, the ARJ21 stumbled through the entire process from design to airworthiness certification. Although the US shadow review was eventually abandoned for various reasons, the airworthiness standards have not been lowered. The most important thing is that in this process, Chinese aviation engineers have accumulated experience in airworthiness certification. It is time to sprint to higher peaks.

Soaring into the blue sky: The construction process of C919

In fact, as early as 2006, in the National Medium- and Long-Term Science and Technology Development Plan Outline released by the state, large aircraft were listed as major projects. In 2008, China established a company dedicated to the development and production of large civil passenger aircraft - Commercial Aircraft Corporation of China, Ltd. In 2009, COMAC's aircraft was officially named C-919, and the dream in the hearts of Chinese aviation people has a new name. If the Y-10 is a set of test questions to test the design and manufacturing level of aircraft, and the ARJ-21 is a set of simulation questions to test the design and test certification of civil aircraft, then this time, what is placed in front of Chinese aviation people is a formal test. This aircraft must not only meet the standards and be absolutely safe, but more importantly, it must be commercially operated, which simply means being able to make money. At this time, the international commercial passenger aircraft market has been monopolized by Airbus and Boeing. Almost all large commercial passenger aircraft flying in the sky are products of these two companies. The aircraft that China is going to build this time is at the same level as the world's most numerous medium- and short-haul passenger aircraft Boeing 737 and Airbus A320. To survive in the fierce competition, my country must take a path that our country has never taken before. Therefore, COMAC must not only aim at the world's advanced level, but also leave enough time to be ahead of the world's advanced level. Only in this way can it have an advantage in future market competition.

The aviation engineer team that was trained in the development process of ARJ-21 began to climb to a new peak. The leader of this team of engineers was the second chief designer of ARJ-21: Wu Guanghui. He knew deeply that the task at hand was not only the development of a new aircraft, but also a pursuit of the world's advanced level. If you don't advance, you will retreat, which is the unchanging truth in the pursuit. In order to race against time, Wu Guanghui led the team to implement the 611 and 724 work systems: 611 means working six days a week and 11 hours a day, while the 724 work system during the critical period of tackling key problems means working seven days a week, 24 hours a day, and the staff took turns to rest. Even so, the difficulty of developing large aircraft exceeded their expectations.

Technical solution demonstration is the beginning of an aircraft design. Its main goal is to determine the layout and shape of the aircraft and the main design parameters. These design parameters are equivalent to setting a goal for the subsequent design, which directly determines the final performance of the product. The technical solution demonstration of C-919 lasted for half a year. Participants included 465 experts from 47 units in the aerospace, electronics, metallurgical materials and other industries and universities in 13 provinces and cities across the country, as well as a consulting group composed of 20 academicians. This is unprecedented in the history of China's civil aircraft development.

Ultimately, the C-919's goal is to be a single-aisle, 150-seat medium- and short-haul mainline passenger aircraft with a basic range of 4,075 kilometers and an extended range of 5,555 kilometers. At the same time, in order to meet market and customer needs and not be defeated in the competition, this aircraft needs to reduce flight resistance, gravity, and carbon emissions. It must be better than competing products in all aspects, and the cost of use must be reduced by more than 10%. In terms of airworthiness standards, the C-919 predicts the development direction of international airworthiness standards and sets many requirements that are higher than international airworthiness standards. In terms of customer experience, from the design stage, the design team first visited a number of airlines to listen to the requirements and opinions of future customers.

As the first customer of C-919, the team of China Eastern Airlines would come to COMAC R&D Center every two weeks to discuss the safety, advancement and comfort of the aircraft and give suggestions on every detail. In order to have a better understanding of flying and understand the aircraft designed by himself from the perspective of a pilot, so that pilots love to fly and passengers love to ride, Wu Guanghui, who is already in his 50s, decided to start pilot training and got a pilot's license. It can be said that this is a commercial passenger aircraft customized by customer needs.

Higher overall design goals put forward higher requirements for each system. In order to meet the indicators, new technologies were widely adopted in the development process of C-919. In aerodynamic design, C-919 adopts advanced supercritical airfoils, which can allow the aircraft to fly at higher speeds with lower resistance. Even ten years later, its aerodynamic efficiency can still be competitive in the market. In terms of structural design, a large number of new aluminum-lithium alloys and composite materials are used to reduce weight. In the selection of fly-by-wire control systems and avionics systems, the world's most advanced technologies are also used, and these technologies come from the world's top manufacturers.

Perhaps, when we open the skin of C-919 to appreciate its airborne systems, we will see the trademarks of manufacturers from all over the world. For this reason, some people will say that the domestically produced part of C-919 is just a shell. However, we should be clear that the development of commercial passenger aircraft is completely different from that of military aircraft. As a civilian product, the most important task of commercial passenger aircraft is to create value in operation. For this reason, civil aircraft manufacturers in various countries have adopted international cooperation to develop and manufacture their own products. Even on Boeing aircraft, there are parts and equipment from Chinese suppliers, not to mention Airbus aircraft, which was originally jointly developed by European countries. The development and service of China's large military transport aircraft have announced to the world China's ability to independently produce and manufacture large aircraft, but in the commercial field, due to the differences in certification systems and usage requirements, using domestically produced equipment is not the optimal solution in business. Suppliers from all over the world cannot be used as a basis for underestimating the design level of C-919. Instead, it is a sign that my country's commercial aircraft industry is in line with the world and moving towards an advanced level. Only in this way can C-919 become an excellent product that "raises the strength of the whole country and gathers the wisdom of the world". As the then vice president of Boeing said: If people could assemble and fly the purchased parts, there would not be only two large civil aircraft manufacturers in the world.

In fact, in the selection and testing of new structural materials, the materials used in C-919 have been tested on more than 2,500 test pieces, and a material specification system and a design performance data system have been gradually established. The selection of this new material can reduce the weight of aircraft-related parts by more than 6%. It is precisely because of the new material specification system and the accuracy of the design performance data that the structural design of C-919 can be carried out very accurately.

The static test of the ultimate load of the full-aircraft maneuvering balance condition is a big test for the aircraft body structure. In this test, the load that the aircraft has to bear is 150% of the load it is allowed to bear during flight, and the extra 50% is called the safety margin. If the aircraft is damaged before loading to 150% load, it means that the structural design strength is insufficient. If the load is far more than 150% but many aircraft are still not damaged, it means that although the aircraft is very strong, the strength is excessive, the design is wasteful, and the structural weight can be further reduced. On the afternoon of July 12, 2018, witnessed by the representative of the Civil Aviation Administration of China, the C-919 was put on the ground test bench, 60%...80%...100%...150%, three seconds of load maintenance, three, two, one. The C-919 successfully passed the maximum load test, and the structural strength met the requirements. In the subsequent static damage test, the C-919 suffered structural damage when the load reached 160%, which was completely in line with the calculation during the design. Accurate structural calculation is the basis of large aircraft design, which also reflects my country's strong aircraft design capabilities. In aircraft design, such tests and calculations are just the tip of the iceberg. Even for products from foreign suppliers, COMAC needs to put forward precise and reasonable requirements and closely integrate and organically blend with the aircraft system. Many of these tasks are being carried out in my country for the first time.

2011, C919, picture from Tuchong.com

On May 5, 2017, the C-919 made its maiden flight. The gray-haired Cheng Bushi was the honorary chief designer of the C-919 and a member of the aircraft design advisory group of COMAC. Facing the large aircraft taking off into the sky, I believe he also knows that the maiden flight is just the beginning, and greater tests are still to come. In addition to the structural tests mentioned above, there are hundreds of airworthiness verification tests and flight test projects that need to be carried out. The ARJ-21 of that year took 300 tests, 528 flight test subjects, 2,942 take-offs and landings, and 5,257 hours of flight to complete the airworthiness verification. The larger, more complex and more advanced C-919 will inevitably face new challenges.

Stall, minimum takeoff speed and natural icing test are called the "three major battles" in the C-919 certification test flight. Stall is a forbidden zone that civil aircraft pilots cannot touch during flight. Once they fly into a deep stall state, the aircraft will be out of control and difficult to recover, and eventually the aircraft will be destroyed and the pilots will die. Stall test flight requires the test pilot to constantly test the boundary of the aircraft's stall state, and test the stall boundary of the aircraft at different speeds and angles of attack. This boundary is like a red line, which will be drawn on the pilot's flight manual in the future to keep the pilot away. The stall parachute is the last straw to pull the test aircraft back once it enters a deep stall state and loses control. This technology was blank in my country in the past, but in the test flight of the C-919, my country completed the test flight of this technology for the first time, which provided a guarantee for the subsequent exploration of the restricted area. The excellent large-slope rolling performance is also an important condition for the aircraft to recover from the stall state. Usually, the rolling slope of civil airliners will not exceed 60 degrees, but in the test flight of the C-919, this data reached 105 degrees. When the aircraft wings are completely perpendicular to the ground, it is still controllable, which also brings full confidence to the test pilots.

The minimum takeoff speed test is to test the minimum speed at which the aircraft can take off. In order to test this speed, the aircraft must taxi on the ground at the maximum nose-up attitude, at which point the tail of the aircraft will rub against the ground. In order to test this performance, a tail skid needs to be installed at the tail of the aircraft to prevent damage. The test pilot needs to gently lift the nose of the aircraft, keep the tail skid rubbing against the ground, and keep the aircraft's attitude stable when the runway is almost invisible to obtain flight data. If the nose is lifted too high, the tail skid will not be able to protect the aircraft and the structure will be damaged. If the nose is not lifted enough, the tail skid will not be able to touch the ground and accurate data cannot be obtained. As the tail skid rubbed against the ground, sparks flew all the way, and the test flight team conquered the test, and the C-919 obtained an accurate minimum takeoff speed, drawing a precise boundary for future safe operations.

In 2006, an KJ-200 crashed in Anhui. In addition to the crew members, there were 34 of China's top early warning aircraft technicians on board, including two generals. This tragic accident was caused by icing on the wings. When flying in areas with extremely low temperatures and high humidity, water vapor will freeze on the surface of the wings. Although the ice looks inconspicuous to the naked eye, it will have a great impact on the aerodynamic shape of the aircraft, causing a sudden drop in lift and an increase in drag, leading to accidents. The natural icing test is to specifically find such an environment to test the flight performance of the aircraft under icing conditions, and whether the de-icing and anti-icing equipment on the aircraft can withstand such an icing environment.

During the test flight of the ARJ-21, in order to find a suitable icing environment, it even flew to the Great Lakes region of North America. However, China has a land area of ​​9.6 million square kilometers. Is it possible that there is no sky suitable for icing tests in such a large land area? In December 2020, under the leadership of the Aviation Industry Flight Test Center, Chinese aviation personnel sounded the clarion call for the C-919 natural icing test flight. In the field where aeronautics and meteorology meet, experts and scholars specialize in using meteorological aircraft to search for icing environments across the country, and have initially mastered the icing resources in Shaanxi, Xinjiang and surrounding provinces, forming icing predictions and real-time detection methods for icing meteorology, and establishing an icing resource database. Yes, the environment that aircraft avoid in normal navigation has become a resource in test flights.

Finally, in 2022, the aircraft fully completed the natural icing test. At the slats of the aircraft, three inches of ice were seen as expected, and the whole process of ice falling off after the aircraft's de-icing device was turned on was recorded. Du Yijie is one of the flight engineers involved in the aircraft icing test. After the plane landed, there was still a large piece of ice on the nose of the aircraft. The maintenance cleaned it up, and it fell to the ground and broke into several pieces. Du Yijie picked up a piece, took it home, and gave it to her son. In the circle of friends, her son held the piece of ice with a bright smile, but he seemed unable to fully understand the deep meaning. And Du Yijie wrote that the gift a mother who came home late gave to her child was a piece of ice that fell from the nose of the aircraft. That's right, this piece of ice is the best gift condensed from the courage, wisdom and hard work of Chinese aviation personnel.

The C-919 successfully completed 729 test flights, including flutter, airspeed calibration, load, control stability, high temperature and high cold test flight, lightning indirect effect test, splash test, and full aircraft emergency evacuation demonstration test. In September 2022, it completed all airworthiness certification work, obtained the type certificate issued by the Civil Aviation Administration of China, and was delivered to China Eastern Airlines at the end of 2022. Chinese passengers will soon be able to take their own large aircraft and travel the sky.

As the C919 took off, along with the cheers, there were also many controversies.

"It is better to buy than to make, and it is better to rent than to buy"; "It is better not to make if it is not domestically produced"... Such statements are widely circulated on the Internet. However, they ignore the major changes that C919 will bring.

In the past, when the development of large aircraft in China was suspended for decades, American and European aircraft took the opportunity to fill China's blue skies and made a lot of money. We have all heard the story of "exporting 1 billion pairs of socks in exchange for an aircraft", but the American story in contrast is "exporting a Boeing 747 can offset the trade deficit caused by importing 12,000 cars."

According to statistics from COMAC, there are 20,563 passenger aircraft in the world in 2021, of which 3,695 are in the Chinese fleet, accounting for 18%. This proportion may increase to 21.1% in the next 200 years!

High demand and weak production will inevitably lead to huge procurement costs!

Buying airplanes is not like buying cabbages. If even a portion of the hundreds of billions of purchase orders were transferred to China, how much domestic demand would be stimulated? How many jobs would be created?

Of course, we must admit that my country currently does not have the ability to produce some key components, such as engines. However, only with large aircraft can we have a platform and demand, which can drive the development of the civil aviation engine industry.

In the past, we used airplanes made by foreign manufacturers and were controlled by them in every way. If a light bulb on the airplane broke, the manufacturer asked you to replace the entire assembly, and you could only swallow your anger. China can't produce engines, so can't it even produce a light bulb? Not really, this is a monopoly, and aircraft manufacturers can use safety as an excuse to refuse to install any parts produced by Chinese companies on the airplane. But now, as a manufacturer ourselves, we have our own large aircraft with independent intellectual property rights, and have passed the airworthiness certification. We have the right to decide on the licensed production of parts, which will break the long-standing monopoly of Europe and the United States and gradually build China's own aviation industry industry chain.

More importantly, the success of C919 means significant progress for China's aviation industry, and will surely attract more and more students to join the aviation profession. We no longer have to worry about a gap in aviation talent or a shortage of manpower. This is the foundation for the continued growth of China's aviation industry in the future!

The launch of C919 will not only benefit the present, but also future generations! There will be more and more domestically-made aircraft flying in the sky; there will be more and more young people who will firmly and confidently devote themselves to China's aviation industry; there will be more and more Chinese people who will board our own large aircraft, travel across the beautiful mountains and rivers of the motherland, and step into every corner of the world.

C919 is just the beginning. For China’s aviation industry to take off, we don’t know how many difficulties it will have to overcome, how many doubts it will have to face, and how much more people’s youth and passion will have to be invested... But we firmly believe that this great goal will be achieved one day!

At the COMAC manufacturing base, there is a Y-10 prototype parked. On the red stone tablet next to the prototype, there are four large characters engraved. They are the firm belief that generations of aviation people have passed down for decades - never give up!

This year, Mr. Cheng Bushi is already 93 years old. Perhaps, Mr. Cheng Bushi will also take this familiar plane and fly across the sky. The sky is still the same one he looked at through the branches decades ago, but the world under this sky is a new world. In this world, his beloved things and his hopes will bring happiness to thousands of people, bring people closer together, and make this world a better place.

This article is a work supported by Science Popularization China Starry Sky Project

Author: Mr. Gou Sheng

Reviewer: Dai Yuting (Professor of Aircraft Department, Beijing University of Aeronautics and Astronautics)

Produced by: China Association for Science and Technology Department of Science Popularization

Producer: China Science and Technology Press Co., Ltd., Beijing Zhongke Xinghe Culture Media Co., Ltd.