The American space plane X-37B has been ＂stranded＂ outside the Earth for more than 400 days.

　　The X-37B project was originally initiated by NASA and later put under the responsibility of the Office of Rapid Capability of the US Air Force. It is possible to bring small satellites into Earth orbit in the future.

　　The US media recently reported that the US Air Force X-37B space plane has been "stranded" in space for more than 400 days since the Falcon 9 rocket of Space Exploration Technology Company entered Earth orbit on September 7, 2017. This mission is called "Orbital Test Vehicle-5" (OTV-5), which is the fifth flight of X-37B. Combined with its highly confidential mission characteristics, many media have dubbed it "mysterious".

　　In this regard, Liu Pingfan, a military expert, said in an interview with the Science and Technology Daily reporter: "At the beginning of its design, the X-37B was designed as a space maneuvering flight test platform for the demonstration and verification of advanced concept technology. Through flight tests, it tested the feasibility, operational applicability and economic affordability of related technologies in the pre-research stage, and verified its ability to enter and leave space and carry out specific tasks. However, judging from these test missions, its related technical indicators have reached or even far exceeded the design requirements, and the nature of the test has been gradually upgraded from general technical performance tests to operational tests to achieve specific military mission objectives, and to some extent, it has actually undertaken military tasks. "

　　The development purpose of X-37B is to realize weaponization.

　　The X-37B spacecraft is an unmanned and reusable space plane developed by Boeing Company of the United States. Its maximum speed can reach more than 25 times the speed of sound, and it is considered as the prototype of future space fighter.

　　Liu Pingfan introduced that the X-37B is a space-orbiting mobile aircraft between the space shuttle and the ordinary plane, which looks like the space shuttle and has some functional characteristics of the space shuttle, the ordinary plane and the satellite. It can quickly maneuver to any place on the earth in two hours and stay in space for a long time. The X-37B can carry different mission loads as needed, perform reconnaissance, early warning, navigation, communication, launching, recovery, capturing or destroying satellites, and even use hypersonic weapons to strike the ground quickly.

　　Data show that from 1994— In 1996, in a research report on future military equipment, the US Air Force suggested that space planes should be used as the future 20-mdash; One of the most important weapons and equipment in 30 years. At the same time, the SMV project plan and the X-37 plan proposed by the US Air Force and NASA respectively envisage the development of a space orbiter. Since then, the two plans have been integrated and a series of preliminary verification tests have been carried out. However, due to the space shuttle Columbia crash and insufficient budget, the project was once cancelled or postponed. Later, at the strong request of the military, NASA resumed the X-37B development plan.

　　"According to the US military, the overall positioning for the development of this aircraft is: through a large number of space flight demonstration and verification tests, reduce the risk of spacecraft development, support the long-term development plan of space, and finally obtain a reusable, long-term on-orbit and orbital maneuver. A spacecraft with the ability to re-launch within 72 hours after returning to the ground. In fact, the purpose of the US Air Force’s space flight test is to achieve weaponization. " Liu Pingfan pointed out, "Compared with other hypersonic technologies such as booster gliding, air-breathing cruise and reentry test flight, the X-37B has no power plant, and needs to be carried by space shuttle or rocket, so it can stay in space orbit for a long time, and it can flexibly change its orbit, with faster flight speed, and can carry a variety of mission loads, and its use is not affected by ‘ Airspace ’ Restrictions have broader military application prospects. "

　　Have the "amazing" ability to change the existing war situation.

　　From 2010 to 2014, X-37B has carried out four space flight test missions.

　　"However, since DARPA took over the X-37B project in 2004, most details of the task have remained confidential except for sporadic fragments disclosed in public reports. Therefore, we can only make some rationality analysis from some public reports. " Liu Pingfan said.

　　"From the public reports, the first space flight test mainly tested two aspects of technology, one is the design of the entire aircraft system itself, and the other is the technology needed for specific tasks, including advanced sensor technologies such as optical cameras and radars. The second space flight test mission was rarely mentioned in public media reports. According to speculation, as an important direction of its military application, the verification of reconnaissance and early warning capability is still an important test content. The third space flight test focused on reusable missions. " Liu Pingfan recalled, "However, in the fourth flight test in 2015, the US Air Force made the test content public for the first time, claiming that the first three missions were mainly to verify the aircraft, and the focus of this mission will be shifted to the test of experimental loads."

　　Earlier, in an interview with the media, Richard McKinney, the former vice minister in charge of the space program of the US Air Force, repeatedly stressed that the role of OTV is only as a pure test platform, not a prototype of a reusable space vehicle.

　　In this regard, Liu Pingfan expressed different views. He pointed out: "The U.S. military deliberately downplayed the operational function of the X-37B, but did not recognize it as a prototype. This is actually a bit of a concept stealing. Looking back on the research and development process of X-37B for more than ten years, it is not difficult to see that X-37B was developed on the basis of X-40A and X-37A. X-37B makes full use of a series of proven technical test results of these two models. At present, the X-37B has met the technical requirements of many SMV projects, and its in-orbit stay time has reached record highs. If the relevant technical state is not fixed in the previous space flight tests, the current X-37B can be completely called a prototype. "

　　"In March 2012, General William Shelton, head of the US Air Force Space Command, answered a reporter’s question on the spot and thought that the X-37B aircraft had ‘ Change the existing situation ’ ‘ Amazing ’ Ability. A series of remarks made by the relevant personnel of the US military in the space field and the frequent actions of the US military in the space field in recent years have increasingly demonstrated the ambition of the United States to seize space hegemony, and indirectly reminded us that McKinney’s views are just an attempt to hide the truth from others. There are indications that the current X-37B is not just a simple test platform. " Liu Pingfan said.

　　Will promote the reshaping of the air and space power of the US military

　　Foreign media reported that the control of OTV series missions was undertaken by the Third Aerospace Test Squadron of schrieffer Air Force Base, Colorado. Schrieffer Air Force Base, known as Air Force Space Command, is responsible for space demonstration, exploration and experimental testing. It collects the information of various artificial celestial bodies running in space and undertakes the task of intelligence collection. This may imply that this unmanned spacecraft is carrying out activities and tasks — — Go down to the earth and go up to space.

　　"At the beginning of the design, the main mission of the X-37B was intelligence gathering. Judging from the functions and tasks of schrieffer Air Force Base in intelligence gathering, it can be understood that it undertakes the flight control work, which can be understood as confirming the intelligence gathering task of X-37B from the side. " Liu Pingfan said that in addition to intelligence gathering, the X-37B may also be equipped with different mission modules to undertake tasks such as military navigation, communication, satellite capture and maintenance according to operational needs. For example, using robotic arms to release, recover or capture satellites, and even repairing, adjusting and upgrading some military satellites with high costs. Considering that air-to-air and air-to-ground missiles powered by traditional turbofans or turbojet engines cannot be used in thin air, the X-37B may also be equipped with hypersonic missiles suitable for air and space operations in the future to implement "global real-time strike".

　　"From a strategic point of view, the successful test of the X-37B project means the establishment of a new ultra-high-speed space-based combat platform, which is in line with the US one-hour routine ‘ Immediate global strike ’ Strategic requirements will become an important weight for the United States to seize the right to control space. " Liu Pingfan pointed out, "Once the project is weaponized in the future, it will equip troops on a large scale, or develop a new space-based combat platform based on it, which will definitely break through the support and support attributes of traditional space forces and promote the structural remodeling and overall reconstruction of US air and space forces, and become a milestone in the construction of American air and space forces. The space power cluster or the air-space power hybrid cluster will play an important role in future military missions. "