what went wrong
analysis
the speed
For many years, trains have attained this and higher speeds in complete safety. Indeed many hundreds of ICE trains had passed the site of the accident without mishap. Of course, these did not suffer a derailment. However, trains elsewhere have derailed at high speeds yet they have been brought to a halt giving passengers little more than bruising and a severe shaking.the track
There is ample evidence that high-speed rail crashes need not be as catastrophic as the Eschede disaster.. In a recent incident in Britain an IC225 sustained a broken wheel and derailed at 100 mph. The train came to a halt safely albeit amid a shower of ballast. In France, TGV trains have been involved in a number of potentially serious situations yet without the consequences of Eschede.
Although undoubtedly, the speed at which ICE 884 was travelling, 200km/h contributed to the horrific death toll, it was within the limits set for the line and certainly within the capabilities of the train. The ICE 1 has a cruising speed of 280Km/h (174 mph). In other rail accidents where speed has been a factor, it was excessive speed that caused the disaster. This was clearly not the case at Eschede. It is therefore necessary to look elsewhere for causal factors.
The line upon which ICE 884 was travelling is not a dedicated high-speed line. It is shared between high-speed trains and other, slower services. It has however been upgraded to permit speeds of up to 200Km/h (125 mph). At precisely the location where the derailment occurred, the layout of the line places considerable impediments to the task of bringing the derailed train safely to rest. The quadruple track allows separation of the high-speed trains from the slower services. Such an arrangement by allowing faster trains to overtake slower ones permits more intensive operation than would be possible on a two-track line. Further, to maximise track usage, it is expedient to provide at intervals, a means of transferring a train from the slow to fast lines and back. But it was just this expedient which served to contribute so much to the scale of the disaster.
Just ahead of the bridge, at a distance of some 300m is a turnout leading from the northbound fast line to the slow line. It was this set of facing points that caused the fourth carriage to stray from the straight-line course it was following. It seems probable that a derailed wheel was running on the outside of the right-hand rail and on reaching the turnout it was diverted towards the slow line and onto a collision course with the bridge supports.
Given plain track, it is very likely that the train, although derailed could have passed safely under the bridge.
historical note
the wheel
One of the wheels has become the focus of investigations into the cause of the accident. The type of wheel used on the ICE 1 trainsets is more usually found on Rapid Transit/Light Rail vehicles...
The original specification for wheels for the ICE 1 sets called for monobloc wheels. However the vibration and noise that was transmitted via the steel suspension units into the passenger spaces was deemed to be unacceptable. A solution was found by providing a wheel with a composite construction which includes a rubber strip between the "tyre" and the "hub". This strip reduces the vibration. Wheels such as this are relatively common on light railway/rapid transit vehicles, but are unique to ICE 1s in high speed trains. The wheels have however served their purpose well and without incident since their introduction. The wheels are inspected regularly although their has been some discussion about the difficulties of such inspections and considerable debate about the method that should be employed and the frequency with which they take place.The debate suggests that there maybe a problem inherent in this type of wheel with suggestions that the destruction of the wheel of Car 802-6 was due to metal fatigue. However, after the accident, all ICE 1s were immediately withdrawn and their wheels subjected to two inspections. This revealed no problems with any of them and the trains were returned to service. Another theory for the disintegration of the wheel is that it struck an object, perhaps a piece of equipment that had fallen from the carriage. If this is the case, it remains to be determined if the construction of the wheel had a role in causing its complete destruction.
the bridge
The line through Eschede had been upgraded for high speeds, part of which involved the removal of level (grade) crossings. The bridge at Eschede was to replace such a crossing. The bridge consisted of a 3-section road deck, the central section being supported on two sets of concrete pillars at either side of the rail formation. These were situated approximately 3m from the nearest rail. This diagram shows the positions of the support columns relative to the line. Car No4 struck those at the top of the diagram, dislodging them and bringing the deck crashing down onto the centre of car No5 as it sped beneath. The energy that the pillars had to absorb may be calculatedconstruction
(mass x velocity)2 Unprotected by any form of crash barrier (unlike motorway bridges), the slender supports proved to be no match for the onslaught of the heavy, fast-moving ICE.
A disturbing feature of the Eschede accident was the sight of the body of at least one of the cars detached from its underframe. It is clear that this car's ability to contain its occupants was severely compromised.1 at the site of the weld.
Modern railway carriage design is the result of long and often bitter experience. The wooden construction of railway passenger coaches in the nineteenth century can be blamed for the high casualty toll in many early rail accidents. The splintering of carriages and consequent spilling of passengers out onto the line was a feature of many "high-energy" accidents. Many died or were severely injured as a result. Through experience it became established that containing occupants within the vehicle in which they were travelling could considerably reduce the number of casualties. Advances in the design of passenger vehicles, particularly the use of steel to create a rigid, enclosed cabin made a major contribution to achieving this aim.
The construction of ICE 1 cars does not follow traditional practice. The floor forms part of the underframe to which the body is attached by welds. The bodies are made from aluminium extrusions which are heat-treated to provide increased strength. A side effect however is to lower the tensile strength, typically by 50%
The accident at Eschede is no the only example of a train bringing a bridge down onto itself
An accident at Granville in Australia had many similarites to that at Eschede. Here, a train derailed, demolished a bridge support resulting in the decking falling onto the train killing 83 people.
Power Car 401 051-8 The power car continued for another 2 Km after the derailment. It was brought to a halt by an automatic application of the disc brakes invoked after the train parted. The regenerative braking system was inoperative because the power supply had been cut after the overhead catenary was demolished. This vehicle will be returned to service. |
Trailer Car 808 802-6 2nd class car. The second vehicle in the train and the first passenger car. Smoking is permitted and video programmes are available. This car was the first to be derailed after a wheel tyre broke. It came to rest about 300m from the bridge. |
Trailer Car 802 609-8 2nd class carriage, third vehicle in the train. The carriage was derailed and stopped aproximately 300m from the bridge. |
Trailer Car 802 311-1 2nd class carriage, fourth vehicle in the train. The carriage was derailed and stopped aproximately 300m from the bridge. |
Trailer Car 802 374-9 2nd class carriage, fifth vehicle in the train. This carriage struck a central supporting column of the bridge, starting its demolition. The car careered across the track and came to rest amongst some trees beside the line. |
Trailer Car 802 340-0 2nd class carriage, sixth vehicle in the train. This car was cut in two by the falling bridge, the front portion coming to rest around 100m from the bridge. The rear part was crushed beneath the bridge. |
802 373-1 2nd Class | 802 037-2 2nd Class | 803 008-2 Service car (Wheelchairs + crew space + telephone) |
804 010-7 Restaurant Car | 801 009-2 1st Class | 801 014 1st Class |
801 806-1 1st Class (Smoking + video + telephone) | 401 551-7 Power Car |
Constructed as a collaboration between a number of manufacturing companies, the ICE1s are amongst the most advanced trains in the world. They are equipped with sophisticated safety equipment including a dual breaking system (regenerative and friction disc) and in-cab signalling. Many of the train's systems are monitored with information being relayed to the driver. There is even a warning that water in the toilets needs to be replenished. There is not however a system to warn that a carriage has been derailed!
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