"The Death Express," who asked him to stop?

by langrentoh1 on 2011-08-24 13:47:19

The Death Express, who made it stop?

25-year-old Hai Ru Wang from He Ze in Shandong province could never have imagined that less than five minutes after she took out her mobile phone to film the interior of carriage number 3115, the train she was on would be rear ended by train D301.

After narrowly escaping death, she sat on a hospital bed and replayed the recorded scenes on her phone: inside the brightly lit carriage, it was almost full of passengers. This short video clip of only a few dozen seconds is likely the only existing footage taken inside the carriage before the collision occurred.

Hai Ru Wang and her husband Wei Dong Cao were seated on the third last row on the right side of carriage number 15 on train D3115. At 8:30 PM, the accident happened without any warning: she felt as if an earthquake had struck and her body began to slide uncontrollably, feeling like she had fallen under the train.

At the same time, Shu Qin Sun, a civilian officer in the armed forces who was located in the second carriage of train D301, was lying on the upper berth of a hard seat compartment converted from a sleeper car, reading a book. Suddenly, she felt the carriage begin to roll violently and her body was shaken fiercely. Luckily, she held tightly onto the railings of the upper berth and wasn't thrown off.

When the accident occurred, the first two carriages of train D301's locomotive were lifted off the tracks at the moment of impact, its head raised high, then plummeted urgently, falling and rolling over onto the muddy ground beneath the elevated railway track which was more than 20 meters high.

As for the last two carriages of train D3115, they were flattened by the locomotive of train D301. After narrowly escaping death, Hai Ru Wang recalled that the last carriage of train D3115 had been compressed to less than one-third of its original volume. The rear half part of the roof of the penultimate carriage was pressed down tightly against the top of the seats inside the train.

Fortunately, the window to the right side of Hai Ru Wang and her husband's seats was shattered by the immense impact, allowing this couple to escape through the broken window within a few minutes of the incident; Shu Qin Sun, relying on her self-rescue knowledge, endured for dozens of minutes inside the fallen carriage before eventually being rescued.

Driver's Shock

About an hour after the rear-end collision, Wei Dong Cao and Hai Ru Wang, prompted by the conductor, saw the driver of train D3115. At that time, he was making a call to report the situation to his superior.

Hai Ru Wang recalled that the driver was slumped sitting beside the railway embankment near the tail of train D3115. She questioned him: "We collided so severely behind us, didn't you know?" Answer: "I didn't know an accident had happened."

This dialogue was confirmed by another passenger on train D3115, Yong Yuan Bao, the secretary of the Wenzhou Rui'an City Literary Federation. At that time, Yong Yuan Bao had given the driver a cigarette. In a CCTV telephone interview on July 25th, Yong Yuan Bao claimed that the driver had told him: "Now I can tell you, it was really someone else (train D301) who rear-ended me, it's not my fault."

Hai Ru Wang also stated that indeed a passenger had given the driver a cigarette. Seeing the driver collapsed on one side, Hai Ru Wang felt sympathy and did not continue questioning, but subsequently, she heard the driver repeatedly muttering these words: "I will never drive again in my life, I am not responsible. At that time, I said we could pass, we should go, but he insisted on making me stop." Faced with the reporter's persistent questioning, Hai Ru Wang firmly claimed that her memory was accurate, "The driver was right next to me, how could I have heard wrong?"

What does the driver mean by "we could pass"? Who is this "he" who gave the order to stop? This sentence may become one of the clues to unravel the cause of this EMU rear-end collision accident.

Professor Zhang Sun from the Urban Rail Transit and Railway Engineering Department of Tongji University analyzed: "If the lightning strike indeed did not affect the power supply for the train's propulsion before the incident, then train D3115 had the power to continue moving, and the driver's claim of 'we could pass' can be interpreted as such."

As for the "he" referred to by the driver, Professor Zhang analyzed that "he" was very likely the dispatcher, "No one else has the authority to order the driver to stop, only the dispatch command can."

Dispatcher's Error?

Before the rear-end collision occurred, the last station where the two trains stopped was Yongjia Station in Wenzhou. An unnamed staff member of the station told the Nanfang Metropolis Daily that train D3115 stopped within the Shuang'ao Village section, "It must be because there was a dispatch command."

If the dispatch command ordered train D3115 to stop, it indicates that before the rear-end collision occurred, Yongjia Station and nearby stations might have already entered "special station control" - at this point, the train would be detached from system control and enter the traditional manual control mode of the station. This signifies that the instructions commanding the train's progress would switch from automatically generated by the computer to manually issued orders.

This also explains why train D3115 left Yongjia Station around 8:15 PM on that day, delayed by more than 20 minutes. After starting, the train moved extremely slowly because once the train proceeded under special station control, the station could notify the train driver that the train must proceed visually. At this time, the train's speed should be maintained at approximately 20 kilometers per hour.

Yue Min Lu, a master of Chen-style Tai Chi who was seated directly behind the couple Wei Dong Cao and Hai Ru Wang on train D3115, verified to the reporters that after leaving Yongjia Station, the train experienced the process of starting, slow movement, accelerating, and finally decelerating. "The train started very slowly when it left Yongjia Station, I found it strange. After moving slowly for two or three minutes, it accelerated and sped up. Then, after driving at a relatively fast speed for two or three more minutes, the train began to decelerate. The deceleration process lasted about one minute. By the time the train had not completely stopped, the accident occurred."

According to railway insiders, if Yongjia Station and Wenzhou South Station indeed implemented special station control, then a complete block section would form between the two stations. A block section refers to logically divided zones on the railway where only one train is allowed to exist simultaneously within the same block section, ensuring that trains do not collide in a rear-end accident.

Under the premise of implementing special station control, while train D3115 was traveling between Yongjia Station and Wenzhou South Station, train D301 would not be permitted to leave Yongjia Station, because this violates the principle that no more than one train can exist simultaneously within the same block section.

Why did train D301 receive the instruction to start at Yongjia Station? Insiders analyzed that the start instruction could only come from the train dispatcher, thus causing two trains to appear within the same block section, which was very likely due to the dispatcher's erroneous command.

After the rear-end collision occurred, An Lusheng, who was urgently appointed as the director of the Shanghai Railway Bureau, attended a teleconference held on July 25th and delivered a speech. On the evening of July 26th, what appeared to be the full text of the speech surfaced on a domestic professional railway forum. According to multiple sources, the content appearing on the forum was very likely the original text of An Lusheng's speech.

The speech mentioned that "when switching from centralized dispatching to special station control, it must be approved by the chief dispatcher of the dispatch office and confirm that the station monitoring personnel are on duty before the conversion can occur," Industry insiders interpreted this as emphasizing the process of switching to special station control, implying that serious violations of procedures occurred before the 7·23 rear-end collision when Yongjia and other stations switched to special station control. Additionally, the article emphasized that "the traffic department should not blindly command traffic," also suggesting the possibility of blind command traffic before the rear-end collision.

According to a Shandong-based passenger seated in seat 56 of the third carriage of train D301, after leaving Yongjia Station, he saw on the electronic display screen in the carriage that the train was traveling at a speed of around 170 kilometers per hour and maintained a relatively fast speed until the collision occurred, without stopping en route.

Professor Xin Sun Xia, an expert in train braking systems from the Institute of Railway and Urban Rail Transit at Tongji University, told the Southern Weekly that according to the technical management regulations of the Ministry of Railways, trains traveling at speeds of 160 kilometers per hour must have a braking distance of no more than 1400 meters, during which time the train requires approximately 62 seconds to complete braking.

Xia also mentioned that even if the driver takes emergency braking measures, the brakes cannot be applied too sharply. Because if the deceleration exceeds the standard, passengers risk being thrown out of their seats due to inertia, potentially leading to casualties.

According to media reports, the instantaneous speed of train D301 when it collided with train D3115 exceeded 100 kilometers per hour, indicating that the driver of train D301 did not implement emergency braking according to the specified braking distance. It is therefore very likely that only when the driver visually noticed an abnormal situation ahead did he pull the emergency brake, resulting in the train using up the remaining short braking distance before it could successfully stop, ultimately colliding with the train in front.

Dingli Feng Shoe Factory in Shuang'ao Village is located less than 200 meters in a straight line from the elevated section where the incident occurred. The factory's office and production building has four floors and is the tallest structure in the vicinity. Before the incident, Chang Xiao Ruan was checking for leaks on the rooftop from the fourth-floor terrace when he witnessed the entire process of the two EMUs colliding.

Chang Xiao Ruan stated that a few seconds before the collision, the headlights of the locomotive of train D301 had flickered several times, and he also confirmed to the reporters that at the time of the incident, the preceding train D3115 had not stopped but was moving slowly.

An unusual detail is that according to the normal timetables of trains D301 and D3115, train D301 does not stop at Yongjia Station but passes through directly. According to the recollections of many passengers on train D301, the train abnormally stopped at Yongjia Station, and the carriage broadcast announced that due to thunderstorms and heavy rain, the train needed to stop at Yongjia Station.

At this point, both trains D301 and D3115 were simultaneously stopped at Yongjia Station. Passenger Yue Min Lu from train D3115 recalled that train D301 was parked on the track to the right of train D3115 within the station. Around 8:15 PM, train D3115 started first, while train D301 remained stationary within the station.

However, according to the normal timetables of the trains, train D301 was scheduled to arrive at Wenzhou South Station at 7:42 PM, and train D3115 was scheduled to arrive at 7:57 PM. Why train D3115 left first from Yongjia Station, thereby leaving train D301 behind, remains an unsolved mystery.

Lightning Strike Mystery

A bigger question is whether the overhead contact lines and signal lines along the affected section really experienced failures caused by lightning strikes during the severe storm and thunderstorm described by locals as "not seen for years." There is still no clear answer.

Professor Zhang Sun said that among China's more than 30,000 kilometers of electrified railway lines, there had never been a similar serious accident caused by lightning strikes before. Therefore, he described the total loss of signals on the EMU line due to lightning strikes and the resulting casualties as a "low-probability event." Currently, it is also impossible to prove that this rear-end collision belongs to such a low-probability event.

The Ningbo-Wenzhou railway implements the CTCS-2 level train control system, which can achieve the transmission of operational permit information and line data to the train, serving as the central nervous system for monitoring the safe operation of the train.

The CTCS-2 system includes three parts: the train automatic protection subsystem (ATP), the train automatic supervision system (ATS), and the train automatic operation system (ATO). In this accident, the ATP subsystem became a widely focused angle.

The ATP subsystem can be equipped on both the train and the station. If the ATP subsystem installed on the train works normally, it can identify signals ahead of the train and the operational environment, thus determining whether automatic deceleration or braking is necessary to forcibly stop the train.

The ATP installed in the station can also recognize relevant signals, timely display them to the dispatcher within the station, and make automatic judgments.

Therefore, even if the onboard ATP subsystem on train D301 failed due to the lightning strike, the station could still issue an emergency braking command to the driver via the GSM-R system, avoiding the tragedy of a rear-end collision.

GSM-R is the railway customized version of the GSM mobile communication system used by ordinary users. Simply put, the voice dialogues between trains and trains, as well as between trains and stations, are realized by a special "mobile phone," which looks different from the mobile phones used by ordinary users but can achieve the function of "making calls."

However, despite the adoption of several technical means on the Ningbo-Wenzhou line to ensure the safe operation of trains, on the night of July 23rd, with flashes of lightning and thunderstorms, they were still unable to prevent train D301 from colliding violently with train D3115.

On July 24th, the Party Leadership Group of the Ministry of Railways decided to dismiss Long Jing, Director of the Shanghai Railway Bureau, and Li Jia, Secretary of the Party Committee, from their posts and investigate them. Industry insiders believe that the reason for dismissing these two individuals is that the section where the rear-end collision occurred falls under the jurisdiction of the Shanghai Railway Bureau, and the Director and Secretary of the Party Committee are undoubtedly the responsible parties.

Notably, Deputy Director He Shengli, who oversees civil engineering and telecommunications, was also dismissed at the same time. Among the responsibilities of railway telecommunications include protection against lightning damage. Whether He Shengli was dismissed because the lightning indeed caused the failure of the signaling system or due to public opinion pressure remains unknown.

However, one detail worth noting is that in his lengthy speech on July 25th, An Lusheng devoted little attention to lightning protection. In the section on "ensuring seasonal safety," "lightning and wind prevention work" was placed as the fourth point in the final part of the section, with the content being "in response to frequent thunderstorms in the area, the telecommunications department must comprehensively carry out lightning protection work." In the first point of this section, An Lusheng emphasized "flood prevention work."

Another detail is that An emphasized in his speech, "we must quickly overcome the faults in the turnout and ATP system, organize technical breakthroughs, and accelerate software upgrades."

Shortly after assuming the position of Party Secretary of the Ministry of Railways on February 12th of this year, Sheng Guangzu twice emphasized transportation safety issues within just five days.

According to public reports, during the nationwide teleconference held at 10 PM on the day he assumed office, Sheng Guangzu, making his first appearance, required all efforts to ensure the continuous stability of railway transportation safety, and the entire railway system must prioritize ensuring transportation safety.

Three days later, Sheng Guangzu reiterated that "the entire railway system must prioritize ensuring continuous stability in safety as the most important aspect of all work." This statement was made during his inspection of the Ministry of Railways Dispatch Command Center, which is considered the "command headquarters for the entire railway system's safe production."

On July 24th, the State Council specially established the "7·23" Accident Investigation Team, gathering experts from various aspects and relevant departments to uniformly take charge of accident analysis and aftermath work. The Ministry of Railways also dispatched a vice minister to participate.