The big bang of science stepping on the
waves, soaring into the sky
, "Kunlong" AG600 scene deputy commander Zhao Jingbo explained in detail its "superpowers"
"Kunlong" AG600 made its first flight at sea.
On July 26, my country's self-developed large-scale firefighting/water rescue amphibious aircraft "Kunlong" AG600 made its first flight at sea. The moment it took off from the waves, the dream of "flying into the sea" since ancient times finally came true.
"Kunlong" AG600 deputy commander-in-chief Zhao Jingbo told the China Youth Daily and China Youth Daily reporter that the sky is Kunpeng, and the sea is the Jiaolong, hence the name "Kunlong". It is not difficult to see from its posture of cutting through the wind and waves, this "swimming plane" and "flying ship" will show their talents in emergency tasks such as forest fire fighting and sea rescue.
For this reason, AG600, as a major aviation equipment urgently needed by the national emergency rescue system, is called the "three large aircraft" made in China together with the large transport aircraft Yun-20 and the large passenger aircraft C919 independently developed by my country. The first flight at sea is an important test of its maritime rescue capabilities.
What "superpowers" does "Kunlong" have
"Kunlong" AG600 is currently the world's largest amphibious aircraft under development. It has the functions of performing emergency rescue, forest fire fighting and many other special tasks. The biggest feature is that it can take off and land on land as well as on water. . Zhao Jingbo explained that "Amphibious is actually equivalent to a cross-border aircraft."
Different from the common airplanes that only take off and land in the air, the process of taking off and landing on the water surface of the amphibious aircraft means that it enters from one medium to another. This requires that the appearance, layout and design of the aircraft must be very different from the land-based aircraft.
The most notable feature of amphibious aircraft is that the upper part is an airplane and the lower part is a ship-shaped structure. Except for the conventional wings, fuselage, and landing gear, most amphibious aircraft have single-wing, single-engine or multiple-engine layouts, and use T-tails. This is to adapt to the characteristics and requirements of hydrodynamic design when glide on water at high speed. On both sides of the wings, there will be two more suspended pontoon devices than ordinary airplanes. This is to enhance the auxiliary supporting effect of lateral stability on the water surface.
From the functional point of view, amphibious aircraft are mostly used to perform some special tasks. Zhao Jingbo said that the AG600, like several large amphibious aircraft currently in service in the world, is mainly used for forest fire fighting, maritime rescue, and related extended missions.
my country’s coastline stretches for 18,000 kilometers, and maritime disasters occur from time to time. Because it is far from land, rescue at sea is very difficult. Zhao Jingbo introduced that at present, most countries in the world use ships and helicopters for maritime rescue, and only a few countries are equipped with amphibious aircraft.
Due to the relatively slow speed of ships, the speed of civil ships is only about 15 to 25 knots; destroyers and nuclear-powered aircraft carriers can generally only reach 30 to 35 knots, "the speed is relatively slow." If a maritime emergency occurs at a long distance in COSCO, the best time for rescue will often be missed if the ship arrives at the distress location.
At present, helicopters are very advantageous in search and rescue near seas and close distances, because they can hover and have strong resistance to wind and waves. However, the helicopter has a short range and the rescue radius is generally within 300 kilometers. For maritime distress incidents that occur in COSCO China over 500 kilometers, it is necessary to have equipment that has a long enough range, can reach quickly, and can land directly at sea in order to snatch life from stormy waves. "Amphibious aircraft have such characteristics. , Especially suitable for sea rescue by COSCO.”
Zhao Jingbo counted all the "super powers" possessed by AG600. In case of a forest fire, it does not need to slow down, it can directly dive to the nearby water surface, gliding at high speed while drawing water quickly, it only takes about 20 seconds to fill up 12 tons of water; More than 4000 square meters. In terms of special missions such as rapid maritime support and search and rescue of COSCO, its maritime search and rescue voyage can exceed 4000 kilometers, and it can rescue 50 people in distress at a time or load airdrop materials of corresponding weight.
What is the difference between flying on the sea and flying over water
The AG600's "amphibious, multi-type, multi-purpose" multi-purpose particularity determines that it has three maiden flights that are different from other land-based aircraft.
According to relevant technical personnel of Aviation Industry Tongfei Zhuhai Base, its maiden flight on land, like most other types of aircraft, has verified the basic functions and flight performance of the aircraft, and is an important link from model drawings to physical products; The flight was carried out on the lake surface to verify that the aircraft had functions such as taking off and landing on the lake surface with relatively small wave heights and drawing water in the face of natural disasters such as sudden fires. The maiden flight at sea will mainly examine the aircraft’s take-off and landing characteristics under sea conditions and the working conditions of the aircraft’s systems in the marine environment, focusing on verifying the aircraft’s ability to resist waves and corrosion prevention and control at sea. At the same time, in view of the corrosion protection problems caused by the high salinity and high humidity of the ocean, the anti-corrosion effect of the aircraft is evaluated, and it is ready for future aircraft to perform tasks such as ocean cargo transportation and water emergency rescue.
Compared with the first flight on the water, the sea takeoff is more difficult. First of all, the salinity of seawater is significantly higher than that of freshwater in lakes and is more corrosive. Therefore, the marine environment has higher requirements for anti-corrosion of the testing machine. At the same time, because of the high density of seawater, there will be differences in the buoyancy of the aircraft in the water and the "stickiness" of the water that needs to be overcome during takeoff. What can not be ignored are the changeable waves on the sea. The waves are high and have high energy. Different types of waves may exist at the same time, and their propagation directions are inconsistent. At the same time, the sea surface is accompanied by ocean currents and wind, and the flight environment becomes more complicated. For pilots, the requirements are more stringent. The sea is more open than the lake, and it is not as easy for a pilot to choose a reference point when landing.
According to the technicians, the first flight at sea is to focus on the inspection of aircraft splash characteristics, wave resistance, acceleration characteristics and surface control characteristics, check the operation of the aircraft systems in the marine environment, and collect sea flight data to provide support for subsequent related work .
In fact, both the water maiden flight and the sea maiden flight include the two stages of "landing from the air to the lake or the sea" and "accelerating taxiing from the lake or the sea into the air". Zhao Jingbo said that especially in the process of taking off and landing on the sea surface, due to the greater fluctuation of the surge, it is more likely to cause the aircraft to bump and sway up and down. The technical term is "pitch". If the pitch diverges, the plane will jump up and down like a dolphin, which is the so-called "dolphin jump". In severe cases, the plane will lose control and dive into the water. Because the density of sea water is about 800 times that of air, if an airplane wants to accelerate to the speed of leaving the water when taking off on the water, the hydrodynamic drag characteristics of the airplane must be better designed to reduce the drag coefficient as much as possible to make the airplane pass the drag peak There is still enough acceleration at time to ensure that the aircraft accelerates to the water speed for takeoff in a short time. The difference between the density of sea water and the density of Lake Neili is also more obvious here.
Whether it is the first flight on land, water or sea, it is the only way for the AG600 to go from a drawing to a test machine and then to the market. It is also a key step to verify the different flight characteristics of the aircraft and ensure that the aircraft performance is realized and safe .
Forced to embark on the road of independent research and development
It is the first time for the aviation industry to develop such a large special aircraft. For the aviation industry, it is also the first time for the aviation industry to develop such a large special aircraft that can take off and land on land as well as on water. ; Looking at the world, similar types of aircraft are rare.
At that time, the team also tried to carry out international cooperation and learn from the advanced experience of foreign countries, but found that foreign countries not only refused to cooperate, but even the purchase of some airborne products, including engines, was blocked. This made the AG600 project development team clearly realize that "the key and core things must be mastered by yourself. When you don't have it, no one will give it to you, and you can't buy it with money." Since then, AG600 was forced on the road of independent research and development.
In order to complete the layout design of water and aerodynamics, the team spent 3 years doing tens of thousands of experiments, making multiple models over and over again, and continuously iterative optimization. "One step at a time, this problem is solved, and some new problems have emerged." Zhao Jingbo said that the team worked day and night, even working overtime during the Spring Festival to do experiments.
Today, "Kunlong" AG600 has broken through a series of key technologies and formed the technical system of amphibious aircraft. It is a domestic civil aircraft with independent intellectual property rights and independent supporting facilities.
Large aircraft is a complex system engineering. AG600 is composed of millions of parts, covering a wide range of professional fields. Its "small core, large collaboration" model has enabled tens of thousands of scientific researchers from more than 20 provinces and cities, more than 150 enterprises and institutions, and more than 10 universities in China to participate, and more than 80 direct supporting suppliers. In this process, the new technologies, new materials, and new processes adopted will also have a radiating effect on my country's economic and technological development, the progress of basic disciplines, and the building of a powerful aviation nation.
During the design and development of the "Kunlong" AG600, China gradually established its own large-scale amphibious aircraft development system, cultivated a team of aviation R&D and manufacturing talents, and established China's own technical standards and systems.
Zhao Jingbo said: "It is a very complex system integration. We call the aviation industry the "flower of industry" because behind it is a concentrated expression of a country's comprehensive capabilities."
Zhao Jingbo often tells others that the Kunlong AG600 is an aircraft that "saves the country from danger and saves people from fire and water." Its blossoming waves of dreams and the sky will also fly on the way for China to become a technological power and a manufacturing power.
China Youth Daily · China Youth Daily reporter Hu Chunyan Source: China Youth Daily