Derailment accident statistics in the USA.

In the USA, according to information published in the Federal Railroad Administration (FRA) website, and processed by ARS, a derailment accident takes place every 6 hours, with financial losses valued at US$ 235 million dollars (2001). The total impact of damage caused by all railway accidents amounted to US$ 320 million, those due to derailments representing 73% of the total. This data does not consider minor derailments which cost is less than US$ 6.600, environmental costs not being assessed either. The number of derailments is really much greater, no general statistics existing that reflect them.


The trend for derailment accidents in the last five years (January 1997 to May 2002) has been very negative, having increased in quantity (27%) and economic impact (39%)
The main cause of derailments is track problems (48%), followed by human factor (25%) and those caused by rolling stock (14%)
The average cost of damage caused by each derailment in 2001 was:

- In general, US$ 105,000

- Freight transport, US$ 116,000

With respect to the track type and the speed at which the derailments occurred, the average cost of the damage caused by each one in freight transport was:

- US$ 493,000 on main lines at more than 45 Km/hour

- US$ 142,000 on main lines at less than 45 Km/hour

- US$ 42,000 on auxiliary tracks (always less than 45 Km/hour)


The above figures should be taken as averages, taking into account all considerable variations involved. The derailments with greatest economic effect amounted to nearly US$ 1 million on auxiliary tracks, US$ 2 million on main lines at 30 Km/hour and US$ 6.5 million on main lines at 85 Km/hour.
Accidents caused by derailments have from the very beginning of the railways seriously affected transport operating companies and staff responsible for driving the train, as well as users and society in general. The financial consequences resulting from this type of accident are, as we have seen, enormous, therefore any means of avoiding or minimising its effects is welcomed by those in charge of this important means of transport.
The transport of dangerous freight, such as chemical products, liquid fuels or nuclear waste, is increasingly censured by public opinion, especially in countries that suffer evacuations brought about by railway accidents. A town is evacuated almost once a month in the USA due to railway accidents, which are mostly due to derailments.
Staff responsible for train operations express great difficulty in detecting the moment when derailment of the first bogie occurs and believe that if they could respond quickly, most serious derailments would be reduced to simple incidents. When no perception of the aforementioned moment exists, train speed remains unalterable. The risk of the derailment extending to other wagons increases in proportion to the time taken in detecting the phenomenon and subsequently stopping the train. Derailments of many wagons do indeed, occur on occasions with substantial financial losses.


The need to reduce operating costs by making better use of available resources frequently makes it necessary to use train formations with several locomotives for traction, considerably increasing the train length. When a wheel comes off the track in these circumstances, the reaction it causes in the composition is even more difficult for the driver to detect, causing trains to run for long distances with detailed wagons.
The incidence of financial loss is increased when the tracks section affected has concrete sleepers, because it is frequently necessary to replace all the damaged sleepers, which are also more expensive than the traditional wooden ones. If the derailed wagon is running in areas where track devices such as check rails, point switches, points, etc exist, or bridges or tunnels, it is very likely that the derailment will extend to other wagons, with disastrous consequences for the whole train. The damage can also affect electricity pylons in areas where they exist and, in cases of double tracks, it can also cause collisions with other units running in the opposite direction, whether they are for freight or passenger transport.


What is the 3DyFAT system and how does it work?

This system is in the process of being patented in most countries in the world, and is adaptable to any freight wagon equipped with bogies, being able to instantly detect the moment at which derailment occurs, causing automatic and immediate braking of the complete train.
Several years of effort were necessary to overcome the initial design and prototype creation phases, as well as workshop and track tests. It is now operating successfully, and we can confidently state that the system, which we call 3DyFATÇDispositivo Detector de Descarrilamiento y Frenado Autom‡tico del TrenÈ, has shown to be really effective as a Train Derailment Detector and Automatic Braking Device, leading ARS to embark on the marketing phase.
Thesystem reduces the sometimes devastating consequences of freight train derailments, thereby representing a major contribution to railway transport safety, with obvious capacity to improve the profits of companies in the industry.
Experience gained from the installation of the first device more than two years ago leads us to affirm that the equipment is highly reliable, covering most of the causes behind freight wagon derailments. The system has functioned well in 100% of cases and has never acted inopportunely up to now without the prior existence of a derailment.
In general terms, the system is a mechanical and pneumatic device installed on each bogie.

The mechanical part is made up of a specially designed pulsator, whose task is to examine the position of the bogie in relation to the wagon chassis or body, with respect to both its vertical axle (relative movement due to curves and the normal curving caused on straight sections) and the horizontal axle crossing the wagon (relative movements of the two bogie axles due to irregularities and bumps on the track). The mechanism is specifically sized for every type of bogie and track, certain tolerances being fixed in accordance with the minimum curve radius on the track, the maximum bumps and according to the type of suspension the wagon has. If these tolerances are exceeded, circumstance that only occurs when bogie derailment takes place, the longitudinal movement is transferred to the pulsator.
On noting this movement, the pneumatic part instantly transmits a pneumatic signal to an automatic valve, whose task is to discharge pressure from the general compressed air collector, and by which the entire train receives the emergency brake order and is stopped. The necessary air pressure for the system to work is taken form the auxiliary air receiver on the wagon itself.


What is the 3DyFAT system for and what does it?

The 3DyFATsystem, as we have already stated, is used to reduce and minimise damage produced to infrastructure, rolling stock and the environment, following a derailment. It is not capable therefore of avoiding derailments, because it only acts after they have occurred.
The 3D and FAT system drastically reduces the damage caused in derailments by stopping the train in a few hundred metres. Without this system, the train could continue for several kilometres with one or various coaches derailed, able to destroy everything in its path.

Listed below are some of the system's most important contributions:

- It reduces the risk of loss of human life by minimising the time the train is running with one or various coaches derailed.

- It avoids multiple derailments, since it is able to start stopping the moment the derailment of the first bogie takes pace, thereby avoiding greater damage.

- The 3D and FAT system makes a major contribution to reducing risks in the transport of dangerous freight, such as chemical products and liquid fuels, leading to greater confidence on the part of those involved with them, from the train's operating staff to customers, and without forgetting official bodies and society in general.

- 3D and FAT adds to the railway company's prestige, improving its external image.

- Hard to assess environmental damage is also reduced by using 3D and FAT

- Due to the reduced risk with this systems, it is reasonable to negotiate a reduction in premium payments with insurance companies.

- It reduces traffic interruptions caused by derailments, improving:

Turnover
Service

- Damage to freight caused by derailments is significantly reduced.

- Staff entrusted with supervising the wagons or freight cars can be employed in other tasks, since 3D and FAT is the best form of surveillance for any bogie derailment. It is possible to consider staff reduction in certain circumstances to increase productivity.


Greater train braking efficiency in the event of derailments leads to better use of the maximum speed admitted on railway lines.
You can assess and put figures to these advantages in your company, in addition to others that you will undoubtedly think of, while calculating the economic saving this systems will represent for your particular company.
When suffering the consequences of a serious derailment, companies responsible for freight transport wonder if it is wise to wait for the next derailment to make decisions. They are not content with talking about safety, especially when they are transporting dangerous freight, but they try to perfect the railway's active safety, which affects rolling stock and track improvements. The appearance of the 3D and FAT system puts a new and powerful instrument at their disposal to reinforce the trains' passive safety and, in addition, significantly improves companies' economic results.


Where is the 3D and FATsystem operating?

This system is operating successfully at the company "Ferrocarriles Españoles de Vía Estrecha" (FEVE), where its entire freight wagon fleet, about a thousand units, currently uses it. FEVE technical staff, who invented and developed the system, have great experience and capacity to transfer it to the benefit of other railways.


Why the 3D and FATsystem?

Various devices and attempts have been conceived in railway history to detect derailments when they occur. The truth is that most of them fail, sometimes due to their complexity and sometimes due to excessive cost. Few overcome the preliminary design and prototype creation phases, most of them remaining as mere "good ideas" or inventions without practical application. This is why the scepticism of many railway experts is based upon unsuccessful experiences.

In the case of 3D FAT, the following features that distinguish it from the rest can be appreciated:

- As with all things that works well, this system is based on simple physical principles.

- It is not a prototype. It is a reality that operates with great reliability on more than a thousand freight wagons.

- It does not use electrical power conductors or electronic devices. It does not need batteries, accumulators or other analogic power sources.

- It works well, independently of the speed at which the derailment takes place.

- It is very simple to install, both on new and used wagons.

- It has a long useful life, similar to that of the freight trucks on which it is installed.

- It remains stable throughout its useful life, without the need for adjustments, following installation.

- Simple maintenance that does not require lubrication, manual activation sufficing in periodic wagon inspections to check the system's effectiveness.


Following activation in a derailment, the system is easily reset without using consumable items of any type. The average cost of the investment needed does not exceed 3% of the cost of a new wagon, the gross pay-back time being 2 years, which represents a very good financial return.

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