Chapter 1174 Financial Support


    Across the world in one hour.


    Strictly speaking, this is not a new concept.


    In the 1990s, the United States proposed the hypersonic cruise missile "Quick Eagle" to replace Tomahawk. The goal was to be able to attack any target within the territory of the main imaginary enemy within one hour.


    However, this plan coincided with the abolition of a large number of projects after the end of the Cold War, and ended in an anticlimactic manner after a few failed experiments.


    In the last life, what really made this slogan ring around the world was the X51A "Waverider" technology verification aircraft, which was only released in 2007. It was planned to end the ground experiment in 2008 and conduct four test launches starting in 2009, and then officially Consider introducing weaponization.


    Of course, the final result is well known -


    We''re setting up a national hypersonics club, and guess who didn''t get the invite?


    In short, in 2005, Chang Haonan shouted this slogan in advance, which is undoubtedly very eye-catching.


    Especially compared with the previous solutions that often use launch vehicles for delivery, the final product of the waverider-like configuration is a cruise missile with a relatively low sensitivity, but no weak deterrence.


    The threshold for use is relatively low.


    Of course, even if you just look at Chang Haonan''s PPT introduction, you can imagine that product design with this configuration is probably the most difficult of all.


    Seeing that all the five configurations mentioned at the beginning had been introduced, Qiao Chenqing, who had been eager to try it out, finally couldn''t restrain his desire to ask questions and raised his hand almost impatiently -


    The big boss had already given him a sample just now, so of course it was not easy for him to speak directly.


    "Excuse me."


    Chang Haonan has basically finished talking about the most important content. Of course, there is still a lot of space to follow, but due to time constraints, it is impossible to talk about everything in detail.


    Therefore, Qiao Chenqing''s question just helped him.


    "Comrade Haonan, you just introduced a total of three hypersonic flight body configurations with military potential. Of course, the fourth one, whether using rocket power or air-breathing power, is relatively conventional, but the first and The fifth type requires non-ballistic movement within the atmosphere for a long time, which is very different from the traditional ballistic missiles and cruise missiles we are familiar with in the past, so how should it be controlled? "


    As the head of the Air Force, he naturally began to consider the issue of weapons combat efficiency.


    Hearing this question that was right in his mind, Chang Haonan smiled, and then turned the PPT directly to more than 20 pages later.


    "For traditional gliding waveriders, during the process of re-entering the atmosphere, they generally choose one of the two ballistic trajectories as shown in the figure. Among them, the Sanger trajectory will perform multiple jumps at the edge of the atmosphere, while the Qian Xuesen trajectory will Only one reentry maneuver, followed by an unpowered glide at the edge of the atmosphere..."


    "But no matter which one, the re-entry and return stage can be divided into the initial re-entry stage, the energy management stage and the final impact stage. Considering the limitations of dynamic pressure, overload and thermal management, it is difficult for a hypersonic flight body to resemble Large-sized airfoils are arranged like conventional aircraft, so it is necessary to control the flight height by changing the angle of attack, and control the flight direction by changing the roll angle..."


    "Technically speaking, the simplest way is to use reference trajectory guidance, that is, select a relatively narrow reentry range before the mission is executed, generate a set of standard trajectories in advance as a reference, and finally design a trajectory tracking law to control the reference trajectory Carry out tracking control so that it coincides with the standard trajectory line..."


    For today''s report, Chang Haonan specially simplified many proper nouns and calculation parts, so Qiao Chenqing quickly understood the contents of the PPT and nodded thoughtfully.


    This reference trajectory guidance is essentially similar to the guidance method of ballistic missiles.


    They all determine a trajectory in advance and then fly along the preset path.


    Essentially, the flying body does not need to know where it is, it only needs to know when to make what action.


    If combined with some measurement and control capabilities, the flight trajectory can also be calibrated to improve reentry accuracy.


    But...the shortcomings are also obvious.


    "Comrade Haonan, you just said that we need to track and control the actual trajectory and reference trajectory of the flying object, but if we want to hit an enemy target, it is impossible to complete this process on the ground...I am afraid the enemy will not cooperate with us. ?”


    Qiao Chenqing continued to ask in a half-joking tone.


    "Yes, so this method can only be used in the technical verification stage to improve our understanding and knowledge of the waverider gliding trajectory."


    Chang Haonan nodded, and then added:


    "Of course, reference trajectory guidance can also be used in the aerospace field. For those spacecraft that exceed the speed of the second universe, it is difficult to solve the overload and heat caused by direct re-entry into the atmosphere, so multi-stage deceleration can be carried out through the Senger ballistics..."


    "Exceeding the speed of the second universe?"


    The other chief who had been silent just now raised his head.


    "That''s right...for example, this technology may be used when returning from the moon or Mars orbit in the future."


    Chang Haonan originally just said it casually, but since someone is really interested in this detail, he is happy to expand on it.


    It just so happens that we can impress our superiors about deep space exploration.


    If possible, it would be great to do a few re-entry tests with the help of aerospace projects. However, the other party just nodded and did not pursue the question further. Instead, he motioned for Chang Haonan to continue the topic.


    The latter then turned to a page of PPT:


    "In short, for a truly practical weapon, it is necessary to adopt a prediction-correction guidance method that does not rely on a specific reference trajectory. Simply put, it means to compare the deviation between the predicted impact point and the theoretical impact point in real time during each guidance cycle. , and then correct the angle of attack and roll in real time based on the settlement results.”


    "However, this method will produce a large number of partial differential equations during the solution process, which not only requires high performance of the missile-borne computer, but may also lead to failure of convergence and guidance failure... My research team and I are working on this There is a certain amount of technical accumulation and research results in this field, but more test data is still needed to ensure the accuracy and reliability of the solution..."


    "As for the last one just mentioned, because the waverider-like configuration always flies at a relatively low altitude in the atmosphere, the control strategy is close to that of existing supersonic cruise missiles, except for the control of rudder surfaces, motors, etc. The performance requirements of the hardware are quite demanding, requiring us to make major improvements in basic capabilities..."


    At this time in 2005, China already had a certain research foundation for bicones and traditional waveriders. The most that Chang Haonan could do was to provide some additional research resources and basic theoretical help.


    Therefore, he naturally focused his attention on the waverider configuration.


    It is inevitable to say a few good words.


    "What about guidance?"


    Qiao Chenqing quickly wrote down what Chang Haonan had introduced before, and then continued to ask:


    "Gliding ballistics can also be autonomously guided by a combination of inertial navigation and starlight navigation. However, cruise missiles always need to rely on external signals, whether it is satellite positioning systems or radar echoes, to find their targets. Will high-speed flight in the atmosphere cause problems? Produce a black barrier similar to that produced by a spacecraft during re-entry into the atmosphere?”


    Asking such specific questions often represents real interest.


    Chang Haonan was overjoyed, but on the surface he still controlled his expression:


    "For hypersonic cruise missiles with relatively low speeds, that is, within the range of 6-8 times the speed of sound, as long as the aerodynamic shape is properly designed, plasma ionization will hardly be stimulated. As long as the mid-course satellite guidance is used like ordinary cruise missiles, It can be combined with terminal active radar/optical imaging guidance.”


    "If the speed is further increased, as you said, the shielding of electromagnetic signals by the plasma sheath needs to be considered..."


    Because this part of the content involves a lot of specific calculations, it is not left in the PPT.


    So Chang Haonan paused slightly when he said this, and then looked at a security guard not far away:


    "Please bring me something I can write on..."


    The latter quickly brought a whiteboard to Chang Haonan:


    "Sorry, Academician Chang, there is no blackboard prepared here at Jingxi Hotel..."


    Chang Haonan shook his head slightly to express that it didn''t matter, and then returned to the stage.


    "I''ll try to explain it in a simpler way..."


    He showed an apologetic smile, and then drew an electromagnetic wave transmission vector diagram on the whiteboard.


    "What we usually call a black barrier is a very broad concept. In fact, the plasma sheath excited by high heat does not absorb all electromagnetic waves indiscriminately, but is non-uniformly dynamic and non-magnetized..."


    "A sharp-nosed aircraft is different from a blunt-nosed aircraft. Its sheath is a layer of structure attached to the side wall of the aircraft. The thickness is only about 2-4 centimeters. In the vertical direction of the side wall, the electron density and collision frequency produce similar effects. The situation of discontinuous surfaces, so for millimeter waves with shorter wavelengths and longer decimeter waves, under certain conditions, it can be penetrated through the plasma layer by applying a magnetic field, etc., to achieve satellite or radar guidance..."


    “…”


    When Chang Haonan reached the end of the story, there were only a few people who were still lowering their heads to record.


    Most of the audience just watched him write and draw on the whiteboard.


    Fortunately, although the process is a bit complicated, the conclusion is indeed very simple.


    It''s that he has a way to make electromagnetic waves overcome the black barrier.


    Most of those who can sit in this room have been exposed to or understood the manned space project, and know what the black barrier is about.


    Therefore, Chang Haonan''s statement is almost a statement that overthrows the world view.


    But with the previous content and his achievements in the past ten years as a foreshadowing, it doesn''t seem that difficult to accept.


    Not long after, a group of leaders started discussing in front of Chang Haonan.


    Now that the theoretical foundation, overall configuration, and research direction are all in place, it is obvious that there is only one last element left before the project is launched—


    Make money.


    (End of chapter)