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          Imagine a train running at 4,000 km/h

          China Daily | Updated: 2017-09-02 10:20
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          File photo / China Daily

          The China Aerospace Science and Industry Corp announced at a forum in Wuhan, Central China's Hubei province, on Wednesday that it had launched research and development in hyperloop, a futuristic mode of transportation that could allow trains to run at speeds of up to 4,000 kilometers an hour. CASIC said they would design hyperloop in a way that would allow "vehicles" to run in low vacuum so as to minimize air resistance, and use magnetic suspension technology to minimize friction. Is hyperloop really possible? China Daily's Zhang Zhouxiang interviewed an expert on the subject and translated CASIC's explanation about hyperloop. Excerpts from both follow:

          Technology faces major challenges

          Zhao Chunfa, a professor who specilizes in magnetic suspension trains at Southwest Jiaotong University

          Hyperloop, or, in more technological terms, ultra high-speed magnetic suspension transportation in vacuum tubes, is the direction of our future research. It will not only make traveling more convenient, but also help to improve many related technologies.

          However, currently we face some major challenges in that field. For example, hyperloop involves high-temperature superconductivity technology, for which we need materials of the tube to be superconductive to relatively "high" temperatures. But when a train would run at speeds of up to 1,000 km an hour, it will generate lots of heat and vibration in the vacuum tube. The question is: Will the materials remain superconductive to "super high temperatures" and violent vibration?

          Besides, for a train to run at more than 1,000 km an hour, its rails have to be very, very smooth, in order to keep the train stable. A flaw of even 0.1 millimeter might cause the train to be unstable making passengers uncomfortable. Sometimes such a flaw could result in the train jumping the rails. And even the most advanced technology today cannot ensure our rails are smooth to that extent over thousands of kilometers.

          Some might argue that the proposed hyperloop technology would allow the train to operate in vacuum tubes, but it would still be a mode of rail transport and has to meet the standards.

          These are only two of the challenges that hyperloop faces. Others include safety concerns, difficulties in making thousands of kilometers-long vacuum tubes, and extremely high costs. This is not to say hyperloop as a technology is a failure ab initio, but it is necessary to conduct fundamental research first, so as to make it practicable.

          Company confident about meeting goal

          Mao Kai, engineer in charge of the hyperloop program at CASIC

          The concerns over hyperloop transportation causing harm to passengers are unnecessary. High speed does not cause any damage to the human body; it is high acceleration that does. Hyperloop trains are expected to have a higher maximum speed than aircraft, but they would accelerate much slowly. For hyperloop trains to cause harm to the human body, their rate of change of velocity would have to be faster than that of an aircraft, which would not be the case.

          Besides, CASIC is not the only organization engaged in hyperloop R&D. US-based companies HTT and Hyperloop One are also conducting such R&D, with the latter even using the term "hyperloop" in its name.

          Compared with the two companies which aim to increase a train's speed to 1,000 km an hour, our goal is to raise it step by step to 4,000 km an hour. And we are confident of reaching that goal, because we are using electromagnetic force to propel hyperloop "vehicles" forward, while the other two companies plan to run hyperloop "vehicles" on wheels.

          As for the major advanced technologies needed to develop hyperloop transportation, including ultrasonic technology, high-temperature superconductive magnetic suspension, as well as simulation and modeling technologies, we are now playing leading roles in all those fields. In other words, we have more mature technologies than our counterparts in other countries at our disposal and we are confident about succeeding in our R&D.

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