Its difficulty lies in getting the trains to keep a safe distance between one another and preventing them from colliding with each other or slower trains, he said, a challenge that may not seem like a big one for slower rail.

"Trains running at 350kmh can equal the speed of airplanes taking off, or at 100m per second," Zhang said.

Only four countries have mastered such technology, he said.

Such expertise has made it possible for the 350-kmh trains to leave the railway station every five minutes during peak hours, and every 10 minutes during non-peak hours, Zhang said.

The second core technology is in synthesizing up to seven rail coordination systems, each with up to 70,000 parts, and making them work as one to maintain track performance, he said. It is something China has also acquired on its own after years of research and experience, he said.

The third core technology of high-speed railways involves the design and manufacture of high-speed trains themselves.

"When a train runs at 350kmh, it will produce an environment of 'negative air pressure'. Designing the high-speed train's air-conditioning system becomes a difficult task, since the train can draw objects into the carriage through any opening, like a big vacuum," he said.

The authorities chose to cooperate with foreign companies that had the necessary expertise, like Germany-based Siemens, to meet such challenges. Under a joint project between the Tangshan Railway Transportation Equipment Company and Siemens, Chinese engineers completed the requisite designs and submitted it to Siemens, who were involved in the industrial certification of the project, Zhang said.

rail completion

The final product, the CRH-3 (China Railway High-speed) train, is unique to China.

"The entire design is made to suit our needs. As agreed, we own the intellectual property rights of this type of high-speed train," the ministry's Zhang Shuguang said.

Except for three trains manufactured in Germany, the rest of the 57 trains were all produced locally, in Tangshan. Each costs 200 million yuan, Zhang said.

The trains on the Beijing-Tianjin line are also upgrades carried out by Chinese engineers based on the 200-250kmh bullet trains, under a cooperation program between China and Japan.

(China Daily July 24, 2008)