J-20 (English:Chengdu J-20, code: Weilong, NAT code: Fire Fang, translation: flame fangs) is a high stealth, high situational awareness, high developed by AVIC Chengdu Aircraft Industry Group Co., Ltd. Invisible fifth-generation air-to-air fighter with mobility and other capabilities.

The J-20 adopts a duck-type aerodynamic layout with single-seat double-engine, full-motion double-tailed tail, DSI drum-inlet air intake, and upper anti-duck wing with pointed arch. The head and body are diamond-shaped, the vertical tail is inclined outward, the landing gear door is designed with a serrated edge, and the body is painted in high-gloss silver (the prototype is dark green). The side bomb cabin adopts an innovative structure, which can pre-close the missile launching pylon on the outside of the silo, and is equipped with new PL-15 and PL-21 air-to-air missiles.

J-20 is the fifth-generation heavy fighter of China used to replace the J-10, J-11 and other models. It was officially established in the same year as the first flight of the fifth generation fighter F-22 Raptor in 1997. The first technical engineering verification machine It was successfully manufactured in 2009 and achieved its first flight at the Huangtianba Military Airport in Chengdu on January 11, 2011. On November 1, 2016, the J-20 participated in the Zhuhai Air Show and exhibited the first two-machine flight. On March 9, 2017, CCTV reported that the fifth-generation fighter J-20 had officially entered the Air Force sequence. On February 9, 2018, the J-20A began to install Air Force combat troops. At the same time, it means that China is the second country in the world after the United States to complete the fifth-generation fighter demonstration evaluation, design, research and development, prototype testing, final production, and final service. On November 6, 2018, the J-20A fighter aircraft was displayed at the 12th Zhuhai Air Show with a new painting, new formation, and new attitude.

Technical characteristics

1.Overall pneumatic

As the first fifth-generation fighter in China, the J-20 combines the characteristics of many excellent fighters already in use around the world, with strong stealth performance and maneuverability. For example, the American F-35's Photoelectric Distributed Aperture System (EODAS) has also been integrated into the J-20 fighter by technicians. The J-20 is the second fighter in the world to use EODAS. The J-20 is the first stealth fighter with a duck-type aerodynamic layout, with a DSI drum-packed air intake.

J-20 adopts single-seat, double-shot, full-motion differential double-tailed tail, DSI inlet (no supersonic inlet with no boundary layer), and duck-type aerodynamic layout with upper anti-duck wing and pointed arch . The position of the J-20's canard relative to the main wing is further forward than the J-10, which increases the force arm and enhances the utility, so the smaller canard can achieve a great effect.

This layout gives the aircraft a superior supersonic control rate, good large elevation angle lift characteristics, and a large instantaneous angle of attack and roll rate. However, the biggest disadvantage of the duck-type layout is the contradiction between the maximum angle of attack and the continuous angle of attack, and the specular reflection echo that produces stronger intensity when the duck wing is deflected affects the head of the aircraft to the RCS (radar cross section) even more than the conventional layout aircraft. Big.

Among the known fifth-generation fighters, only the J-20 uses the pelvic fins, and the F-22, F-35, and Su-57 do not use the pelvic fins. Russia's Su-57 may be able to use thrust steering to supplement the active control of the stability of the large angle of attack. The F-22 and F-35 do not have such capabilities. However, the F-22 engine is a vector engine, and the engine nozzle thrust can be changed up and down. The engine used in the early stage of J20 is not a vector, it is a scalar.

It is reported that the local plasma stealth technology and anti-passive detection coating that the J-20 has already adopted can make the stealth performance of China's fifth-generation fighters reach or exceed the F-22.

2. Vertical tail strip

The duck wings and double tails of the J-20 are fully moving. Among the fifth-generation fighters known abroad, only the Su-57 has a full-motion vertical tail, and the F-22 and F-35 are both conventional fixed tails and movable rudders. J-20 movable edge strip, located between the canard and the wing. The 边-20's side strips are very small and narrow, behind the duck wings. The side strips can be controlled to sag, and the movable side strips can enhance the vortex lift and control the eddy current. The full-motion vertical tail and movable edge strip technology adopted by the J-20 all show the achievements of Chinese aviation designers and the progress and accumulation of Chinese aviation technology over the years. The J-20 also uses advanced technologies such as distributed integrated optoelectronic systems and active phased array radars. As a stealth heavy fighter, the J-20's original "lifting body, side wing, and duck wing" layout makes the aircraft have good stealth and strong supersonic and maneuvering capabilities. Yang Wei believes that since the most powerful equipment is available, it is necessary to use this equipment in the most critical places in the actual combat process and play a pivotal role.

3.DSI inlet

The J-20 adopts an adjustable DSI (without the boundary layer supersonic) inlet, and the convex surface of the three-dimensional complex curved surface (drum-shaped for compressed airflow) cuts the boundary layer in the intake air face-to-face. Then use a pressure gradient to vent to the two corners of the air inlet. Compared to the FRET's CARET inlet, the J20's DSI inlet has the following advantages: 1. The F-22's CARET boundary layer isolation device has been eliminated. The J-20's DSI drum kit subtly discharges the cover layer from above and below the air intake, eliminating the need for this heavy, complex device, reducing weight and complexity. 2, at the supersonic total pressure recovery is at least not worse than the F-22 CARET, it is likely to be better. 3. Sub/transonic speed provides more airflow for the engine to work smoothly than CARET. Considering that the J-20 DSI is a new generation of DSI developed after accumulating a lot of experience of Snapdragon DSI, it will inherit this advantage of Snapdragon DSI. A notable feature of the J-20 is the two vents on the side of the inlet, which are designed as hexagons for covert and covered with a grid. The common saying on the Internet is the vents of the fuel/air cooler (ACFC/heat exchanger) (exhaust in front of the intake air), which is part of the Aircraft Thermal Management System (TMS). Because the J20 is equipped with a high-power active phased array radar (AESA), the heat generated is greatly increased. In order to solve the heat dissipation problem, the air cooling of the aerospace equipment of the previous generation fighters is different, and the new generation liquid cooling system is adopted according to the research. The system is divided into two circuits before and after, and a special coolant is used. The coolant flows through the front circuit to take out the heat of the aeronautical equipment such as radar, and then enters the rear circuit and flows through the fuel tank to transfer the heat to the fuel, because the latter has Greater heat capacity. The last heated fuel is discharged from the machine through a fuel/air cooler. This liquid cooling method has been adopted by F22 and F35 and is one of the standard equipments of the international standard five-generation machine. However, the 散热20 ACFC's heat exhaust vent is located outside the intake port and is easily detected as an infrared radiation source from the side below. In contrast, the F22 and F35's cooling vents are on the back and face up, making them look more concealed.

4. Power fire control

Mr. Yin Zhuo confirmed that the J-20 is a domestically produced engine and basically meets the fighting needs of the J20. The turbofan-15 is under development, and after the service of the turbofan-15 in 2019, the performance of the J-20 fighter will be significantly improved. And said that the J-20 has been delivered to the troops for 4 or 5 months. Like the Su-35 fighter, the J20 also uses the integrated fire control system. The integration of flying fire push integrates flight control, fire control, and engine control in software to maximize the power of 1+1+1>3. The flight control supervises the speed, altitude and attitude of the aircraft, the fire control supervisor constitutes the weapon launch condition, and the engine control supervisor provides sufficient thrust. Traditionally, flight control is dominant. Only when the aircraft is maneuvered to the appropriate launch position, the weapon can be effectively launched, and the control is only the power guarantee of the flight control, according to the subordinate position. After the integration of the flying fire, the fire control may become dominant at a certain time. After the pilot specifies the target position, the flying fire pushes the hand to transfer the aircraft to the optimal launch position as soon as possible, and automatically launches the weapon at the optimal time.

5. Cockpit system

(1) Screening

The J-20 cockpit is equipped with two large-screen large-screen displays connected together. This layout has been applied from the previous F-35. The size of a single screen should be around 12 inches. There is no connection frame between the two displays. Can be used to merge and display larger images.

(2) Touching

The J-20's display uses touch sensing technology.

(3) voice control

The main screen on the J-20 machine can be controlled and adjusted by sound, which means that the aircraft can be controlled without the need for hand movements.

6. Weapon configuration

According to the 2013 J-20 bomb test flight photos, the side bombs of the J-20 can carry one missile each, and the main bomb bay has six pylons, which can carry six missiles. The J-20 is equipped with 4 external points, which can increase the amount of bombs at the expense of stealth. In the process of receiving the enemy, the J-20 can use airborne air-to-air missiles to attack enemy aircraft, plus future missiles that can be launched at large angles off-axis.

The optional equipment for the J-20 is as follows:

Long-range air-to-air missile: 霹雳-21;

Medium-range air-to-air missile: 霹雳-12D or 霹雳-15;

Short-range air-to-air missile: 霹雳-10;

Precision guided glide bomb: Lei Shi-6, Feiteng-7;

Cannon: A 30×165 mm GSH-301 single-tube transfer aircraft gun.