A crash on one of Shanghai's newest subway lines, the latest stumble in China's rush to roll out modern services, is focusing attention on the use of high-tech signal systems that at times are anything but fail-safe.
The collision Tuesday, which the government says injured 284 people, revived complaints that China is sacrificing safety in its zeal for fast results.
The subway operator, Shanghai Shentong Metro Group, said one of its trains crashed into another near the city's scenic Yuyuan Garden due to problems with signal systems supplied by a state-owned venture whose equipment was implicated in a deadly bullet train crash in July.
It was not the first problem on the line. A mishap involving the misdirecting of a train two months earlier had resulted in assurances of no more accidents from the maker of the signal system, Casco Signal Ltd.
"We certainly intend to get to the bottom of this," the metro's chairman Yu Guangyao told reporters.
Casco, a joint venture of China Railway Signal and Communication Corp., or CRSC, and France's Alstom, SA, was set up in the mid-1980s and is a major supplier of signal systems and other electronic equipment for China's railways and subway systems.
It also supplied a centralized traffic control system for the railway in east China's Zhejiang province where two bullet trains crashed on July 23, killing 40 people and injuring 177.
While the two systems are not the same, the problems with signaling and communications on the subway's "Line 10" raised eyebrows: At the time of the crash, the crowded trains were operating at lower than usual speeds and being directed via phone by subway staff rather than by electronic signals.
High-tech automatic train protection systems, installed to improve safety while allowing more trains to travel within shorter intervals, normally would signal the presence of the train, preventing another from approaching. But such systems sometimes fail due to circuit problems, as with a June 2009 Metro train derailment in Washington, D.C. that killed nine people.
Like the bullet train crash, which experts say resulted both from equipment and human error, Shanghai's problems likely are not limited to the signaling equipment.
"There is no doubt that the signaling equipment is the most direct and obvious cause," said Li Hongchang, a professor of economics and management at Beijing Jiaotong University. "The deeper cause lies in maintenance, management and even in whether contracts were awarded in a fair and open way in the first place."
Staff at Casco's headquarters refused comment Wednesday.
CRSC had declared August a "signaling quality" month, deploying engineers to inspect projects and reduce risks, it said in an announcement on its website.
Alstom has 10,000 employees in China, where it has been supplying trains and equipment to China for over 50 years. Its Urbalis signaling system, the one being used on Line 10, is used on at least seven subway lines in China, including several in Beijing, three in Shanghai and one in Shenzhen, according to a company press release.
China's multi-trillion dollar building boom is knitting the country together as never before, with high-speed trains, smooth new super highways, cruise terminals and brand new airports.
But many of the projects, built at hyper speed to meet deadlines that often appear geared more to political grandstanding than safety, have fallen prey to quality and safety problems.
"Given the serious traffic jam problems in big cities like Beijing and Shanghai, generally it is better to have more subways and have them earlier," said Li, the professor.
"But the rush is too hot in some places, too many subways built too quickly," Li said. Construction often starts before projects are fully designed to save time, he said.
The momentum to build quickly and massively is built into a system dominated by state-owned companies whose party-appointed top executives often enjoy insider influence with the officials awarding contracts.
CRSC, for example, is among the many big state companies that have thrived on China's massive railways buildup, further fortified by huge cash pools from share listings. Most of the company's overseas projects, according to its website, have been in the developing world _ North Korea, Pakistan, Iran and Tanzania _ or at home.
The subway crash was a shock for Shanghai, a city of 23 million that prides itself on its fancy new infrastructure _ roads, airports, ports, tunnels and subways all expanded dramatically ahead of the city's 2010 World Expo.
But as with elsewhere in China, the cracks in the veneer already were showing, just like the recent reports of shattering glass and crumbling concrete at the city's new Hongqiao International Airport terminal.
Tuesday's was the third system failure in two months on the subway's "Line 10", which reportedly was set to switch to completely automated operations next month, eliminating the need for train attendants to drive or operate the doors of the trains.
Such high-tech features are worlds away from the long bicycle and bus commutes of the past. But they are not always worth it, said Zhang Xide, an economics professor at the Chinese Academy of Governance.
"Infrastructure investment is irreversible," Zhang said. "If something goes wrong, the cost is high."
Researchers Fu Ting in Shanghai and Yu Bing in Beijing contributed.