Rebirth of science and technology academic master

Chapter 297 Transport Aircraft Review (22)

Chapter 298 Transport Aircraft Review (2/2)

Strategic transport aircraft are divided into three grades, 600-ton class, 400-ton class and 200-ton class!

There is only one 600-ton class, and that is the An-225 ‘Dream’ transport aircraft. The aircraft has a take-off weight of 640 tons and a load capacity of more than 300 tons.

There are two 400-ton strategic transport aircraft, namely the American C-5 Galaxy transport aircraft and the An-124. The C-5 Galaxy transport aircraft has a maximum take-off weight of 379 tons and a load capacity of 129.3 tons. The An-124 ‘Ruslan’ transport aircraft has a maximum take-off weight of 405 tons and a load capacity of 150 tons.

China's Y-9 transport aircraft cannot actually be called a strategic transport aircraft. Its maximum take-off weight is only 65 tons and its load capacity is only 20 tons. It is a medium-sized medium-range transport aircraft with a load capacity of 20 tons.

China's real strategic transport aircraft is actually only the Y-20. The Y-20 has a maximum takeoff weight of 220 tons and a load capacity of 60 tons. This transport aircraft first flew in 2013 and is not yet in service.

The Y-20 also had an ill-fated fate. As early as 1993, XAC began the preliminary demonstration of a large transport aircraft and invested 3 billion in preparations. In 1997, XAC proposed to the military a plan to develop a large military transport aircraft. In 2001, it proposed the construction of a large transport aircraft. XAC's strategic plan is to develop and produce 200-ton large aircraft as its goal, significantly improve aviation manufacturing technology and processing capabilities, and achieve a major leap in the development and production of 100-ton to 200-ton aircraft.

From the premise demonstration in 1993 to the successful first flight in 2013, the Y-20 took 20 years to develop, with more than 30 billion yuan invested in research and development, and the aerospace engine had to be from Russia.

Nowadays, the Y-30 transport aircraft that Qin Yuanqing has come up with is still 200 tons, but its load capacity has been greatly increased. It is almost twice as big as the Y-20, and its range is also twice as long. It is also a model with independent property rights. The transport aircraft, including a series of core technologies such as aero-engines, are all of its own.

If strategic transport aircraft were not divided into 200-ton, 400-ton, and 600-ton classes, it would actually be most appropriate for the Y-30 to be classified into the 300-ton class, rather than the 200-ton class with the Y-20.

The aircraft engine successfully passed the review, and next came the structural part of the Y-30 transport aircraft. Qin Yuanqing personally participated in the review.

"The Y-30 adopts the conventional layout of a large transport aircraft. The wing is a cantilevered single wing with a leading edge sweep angle of 25 degrees. The NASA winglet is 2.90 meters high and a cantilevered T-shaped tail. The connection between the vertical stabilizer and the fuselage is forward. There is a small dorsal fin extending, the embedded rudder is divided into upper and lower sections, and the elevator is divided into two sections. The vertical tail has a special design, and there is a tunnel-shaped space inside, which allows a maintenance personnel to climb through to perform overhead operations. Maintenance of horizontal tail. Hydraulic retractable tricycle landing gear, reliable gravity emergency free lowering. The front landing gear has two wheels, and the main landing gear has 6 wheels. The front landing gear is retracted forward into the fuselage, and the main landing gear rotates 90° It is retracted into the fairings on both sides of the fuselage and can be used on paved or unpaved runways. The landing gear is equipped with a carbon brake device." Qin Yuanqing pointed to the aircraft model, then turned on the computer, and a very clear three-dimensional diagram appeared on the computer. and animation simulation.

Compared with aircraft design in the 20th century, which relied on manual drawing, or computer-assisted and hand-drawing as the mainstay, industrial software has been developed to this day. Whether it is calculation of structural mechanics or drawing, the time required has been greatly reduced. workload and improved R\u0026D progress.

Why in the past, the data involved in aircraft design were just a few train skins? It was because there were too many drawings and data involved, but it is different now. A few train skins data may be 1G or 2G drawings when worked on the computer. .

"If necessary, the Y-30 can make a short-term emergency landing on unmaintained roads. It is for this reason that the landing gear design indicators are very high, extremely strong and earthquake-resistant! In addition to the traditional shock-absorbing struts of the main landing gear In addition to the hydro-pneumatic shock absorber, it also adopts a front and rear double strut configuration. Each pillar is equipped with three main wheels. When landing, the three main wheels of the rear longer shock absorber strut land first. When the pressure reaches 90 degrees, the front shock absorber The three main wheels of the earthquake props will land again." Qin Yuanqing said.

Others gasped, not expecting Y-30 to have such considerations.

Strategic transport aircraft are different from civilian passenger aircraft. Civilian large passenger aircraft pursue safety, comfort, and economy, while strategic transport aircraft require durability and meet the special battlefield environmental requirements.

The reason why the Il-76 and C-17 Globemaster are famous all over the world is because these two strategic transport aircraft are very durable. Even if there is no runway, they can land in deserts and grasslands in emergencies.

On the battlefield, there is often no time to properly build a runway, nor are there the conditions.

In fact, compared with the original C-17 Globemaster, the current Y-30 transport aircraft has a fuselage structure that uses a large amount of alloy materials and review materials. The weight of the aircraft is reduced by 30%, but the structural strength of the aircraft is Much higher.

This is the advantage of latecomers. With the development of the times, materials have made rapid progress, resulting in the application of new materials, which can improve the performance of the fuselage. For example, the performance of the landing gear has improved a lot. It is based on this that we can significantly improve the performance of the fuselage. Increase load capacity.

After Qin Yuanqing finished his introduction, the experts asked questions one by one. For some simple questions, Qin Yuanqing directly ignored them and let them check the calculations by themselves. For some valuable questions, Qin Yuanqing answered them one by one.

The entire fuselage structure review lasted for a whole day, and was basically led by Qin Yuanqing, supplemented by Harbin Institute of Technology and Beihang University.

The following is the review of the avionics system. In the cabin, three medium-sized LCD displays are spliced ​​together to form a large LCD display. After being synthesized with a special algorithm, the three displays can jointly display large dynamic images. It can be said that this is also the era. The advantages of development, after all, at this time, display technology is far from comparable to that of the 1980s and 1990s. Today's display technology is too advanced.

Through the integration of computers, one can monitor the dynamics of the aircraft in real time, including engine status, flight speed, etc., and will immediately alert if there is a problem with any part. And there is one difference, that is, the Beidou navigation system has been introduced, and Beidou can be used for navigation.

For example, the shared integrated processor on the Y-20 has an operation speed of 100 billion times per second, which is also a very big reform and innovation.

Some people may think that 100 billion times/second is very low, but you must know that this is for military use. All process standards of military computer chips are higher than those for civilian use, and they even use sapphire substrates. It must be resistant to high temperatures, low temperatures, rapid temperature changes, and radiation resistance.

Military computers have an obvious feature, which is durability. Ordinary civilian computers cannot compare with military computers.

Otherwise, when the aircraft is flying at a very fast speed at an altitude of 10,000 meters, its avionics system suddenly crashes, which is simply very fatal.

In this regard, it can be said that it has adopted China's most advanced avionics system design. The avionics system alone is much higher than that of fourth-generation aircraft.

In this regard, many experts have put forward conservative opinions. For example, regarding the use of displays, they feel that mature military displays can be used. Displays like the Y-30 are brand-new technologies and cannot be guaranteed in application.

However, Qin Yuanqing argued that if everything was conservative, many new technologies would not be applied or verified, and they would not even have the courage to try, so how to promote the development of technology.

The last thing is the carrying design. The huge space allows the Y-30 to carry two 96 main battle tanks at the same time for battlefield delivery. It can also carry 250 infantrymen at the same time, and can directly project the force of two companies.

Moreover, the Y-30 adheres to the characteristics of the C-17 Global Dominator. It can transport and unload materials in the middle and rear cabins at the same time, and various air-lifted vehicles can be driven directly into the cabin. There is a parachute hatch on both sides of the tail of the fuselage, and there are two water landing emergency exits on the top of the tail fuselage and on the top of the fuselage in front of the wings.

There is one thing that Y-30 is better than Y-20, that is, the engine power is greater, but the fuel consumption is about the same. The original engine fuel consumption is too high, twice that of Y-20. Nowadays, new technologies have reduced fuel consumption, making the use cost of Y-30 slightly higher than that of Y-20.

The cost of use is also a cost that transport aircraft have to consider.

"According to our budget, the cost of each Y-30 is 800 million yuan, which is approximately US$130 million!" An estimate was also given regarding the cost of the Y-30.

The Y-30 uses many new materials, such as titanium alloys, nickel alloys, and many review materials, which makes the cost of the Y-30 very high. Of course, compared with the cost per aircraft of the American C-17 Globemaster US$250 million is still a lot cheaper.

American products are good, but there is one disadvantage: they are expensive. No matter what product they are, they are always a lot more expensive.

And some products will not be sold to you even if you have money!

This cost is actually similar to that of the Y-20, because the Y-20 uses the D-30KP2 engine. According to the 2010 Russian Saturn Engine Company procurement contract, 224 D-30KP2 engines totaled US$657 million, with an average of $3 million for the engine. The Y-20 needs to be equipped with four D-30KP2 engines, which means that the engine cost alone is $12 million.

However, the Y-30 aero engine can be produced by itself, which can reduce the cost invisibly.

Otherwise, according to American standards, the cost of the Y-30 is estimated to be 300 to 350 million US dollars!

The RMB is currently in a stage of continuous appreciation. Last year, the average exchange rate was 6.144 RMB per US dollar. In the first half of this year, the exchange rate stayed at 5.98 RMB.

However, because China is accelerating its progress towards mid-to-high-end manufacturing, China's export volume once again hit a record high, reaching 350 million tons, a year-on-year increase of 30%, setting a new historical record. China’s imported crude oil alone now exceeds US$200 billion a year.

It can be said that the cost of the Y-30 is definitely quite satisfactory and is within the acceptable range of the Air Force. And everyone knows that with mass production, the cost will drop significantly. After all, once some things are mass-produced, the price will naturally decrease.