Topic of the article: The use and development of the airspeed tube in modern fighters The airspeed tube is a device that feels the total pressure and static pressure of the air flow and transmits the measured pressure data to the atmospheric data computer and flight instruments to measure the flight speed of the aircraft. Airspeed tubes are commonly used on modern workhorse fighters, but installing an airspeed tube in the nose can affect the stealth of the fighter and may interfere with the radar system.
As a result, many countries developing new generation or improved fighters have eliminated nose airspeed tubes in favor of smaller L-shaped airspeed tubes. The L-shaped airspeed tube also senses the total and static pressure of the airflow and is able to transmit data to a computer to calculate the flight speed of the aircraft. In general, airspeed tubes still play an important role in modern fighters, and the use of airspeed tubes is not the only criterion to measure the advanced degree of fighters, but also consider factors such as the cost of fighter use.
The latest batch of F16Block72 fighters of the United States F16 fighter has canceled the nose airspeed tube and replaced it with 4 L-shaped airspeed tubes. In contrast, the F16Block70 still uses an airspeed tube design. During the testing phase of fifth-generation fighters, airspeed tubes are often used to improve stability. For example, China's J-20 and J-35, the United States' F22 and F35, Russia's Su-57 and South Korea's KF21 fighters all use airspeed tubes in the process of flight test finalization.
So, the question is: why do China's J-11B series fighters still use the airspeed tube design after the comprehensive upgrade?In order to answer this question, we need to take a look at the development of China's J-11 series fighters. In the early 90s, in order to improve the comprehensive combat effectiveness and modernization level of the PLA Air Force as soon as possible, China imported more than 70 Su-27 series fighters from Russia, of which Su-27SK fighters were the mainstay.
These fighters were equipped with several elite aviation units at that time and became the absolute trump card of the PLA Air Force. However, due to the inability to import fighters to be equipped in batches, China reached an agreement with Russia in the late 90s to import the production line of Su-27 fighters from Russia, and began to independently produce Su-27 fighters with the supply of key components from Russia. This localized standard Su-27 fighter is called the J-11A.
Although the J-11A fighter basically belongs to the domestic version of the Su-27 fighter, the improvement is not large, because our country is not completely satisfied with the performance of the Su-27 fighter. By the beginning of the 21st century, China produced a total of 104 J-11A fighters. Since 2001, China has launched the J-11B project. In view of the fact that the problems of the old, bulky and bulky equipment system of Russia have not been fundamentally solved, the goal of the J-11B project is to comprehensively upgrade the model.
From 2004 to 2005, China comprehensively replaced, upgraded and improved the radar and avionics systems of the J-11A fighter. Composites are used in key locations such as wing skin, vertical tail, flat tail, etc. The J-11B fighter uses a 1474 pulse Doppler fire control radar, which can attack 2 targets at the same time, a glass cockpit, dual-stick control, integrated avionics and a composite navigation and positioning system. Despite the use of advanced technology, the J-11B fighter still follows the airspeed tube design.
The J-11B fighter is lighter than the J-11A fighter by using a large number of composite materials and new processes to reduce the empty weight5 tons. From the beginning of production in 2007 to the suspension of production in 2015, China has produced more than 320 J-11B fighters and equipped them with the PLA Air Force and Naval Aviation Units. This shows that China is very satisfied with the comprehensive performance of the J-11B fighter.
However, due to the fact that after 2016, China began to mass-produce J-16 fighters with strong performance and is known as one of the pinnacles of the four and a half generations, and the J-11B fighter has insufficient performance and is unable to cope with the situation due to the improvement of the four-and-a-half-generation and fourth-generation fighters of neighboring countries. After all, the J-11B fighter basically uses the technological level of the early 21st century.
Therefore, in recent years, China has greatly upgraded and improved the J-11B fighter, and has successively begun to produce the upgraded J-11BG fighter. The J-11BG fighter adopts the mature technology of the J-16 and J-11D, two four-and-a-half-generation fighters. It is equipped with a new generation of active phased array radar, which has a significant increase in reaction speed and detection range.
At the same time, the J-11BG fighter was replaced with a turbofan 10B high-power engine with greater thrust to improve the propulsion and payload capacity. It is capable of using precision guidance for a wide range of missiles, electronic warfare pods, anti-radiation missiles, stand-off ammunition dispensers, and more**. In addition, the integrated avionics system of the J-11BG fighter has also been completely replaced. After a comprehensive upgrade, the comprehensive combat level of the J-11BG fighter has reached or approached the level of the fourth-and-a-half-generation fighters.
Although the J-11BG fighter has strengthened its multi-purpose combat capability while maintaining excellent air superiority combat capability, its main task is to seize air supremacy. Of course, compared with the latest J-16, there is still a certain gap between the J-11BG fighter and the ground-to-sea capability, payload capability and attack capability. It should be noted that the mid-term improvement upgrade of the fighter will not be able to reach the level of the latest model in any case. The J-11BG fighter still uses airspeed tube technology.
Even after several upgrades and improvements, the mid-term models of the American F-16 and F-15 fighters still do not reach the level of the F-15EX and F-16 Block 72. This is because the new model has been fully adjusted and improved in the early stage of design, and the body layout is more suitable, which is an advantage that the mid-term model cannot match.
Therefore, when carrying out a comprehensive upgrade, in order to consider the original design and cost of the airframe, the mid-range model fighters will still use the traditional airspeed tube. For example, the J-11BG fighter, although fully upgraded, still uses the traditional airspeed tube. The J-11A fighter not only has an airspeed tube on the nose cover, but also an interface to a series of equipment such as lightning protection strips, infrared imaging detectors (IRST), communication antennas, etc., which is expensive.
Thus, in the process of upgrading, the fighter will make only the necessary improvements, and no unnecessary components will be added. In addition, not all newly designed fighters have eliminated the nose airspeed tube. For example, newly designed fighters such as the J-10C, J-16 and J-15B all use the design of the L-shaped airspeed tube on the side of the nose. Therefore, the use of traditional airspeed tubes does not mean that the performance of fighters is backward, and it is not directly related to the use of a new generation of active phased array radars.