Background
Saltsjöbaden is a town of 9463 people (as of 2020) in the southeast of Sweden, located 16km/10mi east-southeast of Stockholm and 175km/109mi east of Örebro on the coast of the Baltic sea (both measurements in linear distance).
Saltsjöbaden (translating to “the salt baths”) is the terminus of the Saltsjöbanan, an 18.6km/11.6mi mostly single-track electrified rail line connecting nearby Stockholm with the coastal town, allowing residents of the big city easy access to the town’s beaches and recreational facilities. Opening in 1893 the line is exclusively used by passenger trains at speeds of up to 70kph/43mph. There is no automatic train control system, it is entirely down to the drivers to obey signals and speed limits and to stop their trains at the platforms. Until 2000 the Saltsjöbanan was connected to the rest of the Swedish railway system (by track, there were no services crossing over to the main network), since then it operates as its own, completely separate system. Today the line, operated by the British Arriva-company, sees around 17 thousand passengers per day.
The train involved
On the 14th of January 2013 a four car train had been parked at the depot at Neglinge (1.6km/1mi linear distance from Saltsjöbaden) late in the evening, having finished the day’s service. It consisted of the leading C10 motor car number 2887, the trailing C11 number 2888, and another unit made up of C10 number 2893 and 2894. The trains are based off the C-trains used for the Stockholm metro, having been adapted for the Saltsjöbanan by being converted from a third rail electricity pickup to pantographs on the roof (for the overhead wire) and widening elements down the sides to fill the larger gap between the trains and the platforms. A C10 (motorized) is always permanently coupled to a C11 (unmotorized), Saltsjöbaden is usually served by four car trains consisting of two units. Introduced in 1975 (except for one unit that was added in 2001) the units measure 35.24m/115.5ft in length at a weight of 42 metric tons and can carry 288 passengers (50% seated 50% standing) at up to 70kph/43mph.
The accident
On the 15th of January 2013 at approximately 2am a cleaner was working on the trains parked at the depot. The drivers and control center staff had gone home, with no trains running that late at night/early in the morning there was no need for an operational crew to be present. There were only a shunting worker and the cleaner present.
At 2:20am the 20 years old cleaner was almost finished working her way through C10 number 2887 from the back, ending up in the driver’s cab. At 2:22am, as the woman was about to leave the train, it suddenly started up and left the depot. Quickly picking up speed it ran right through the following station at 70kph/43mph. With no one to reach on the radio the cleaner couldn’t ask how to stop the train. The downhill track let it breach its technical top speed, reaching 80kph/50mph as it reached Saltsjöbaden station. The buffer stop at the end of the station was designed to stop a train at up to 40kph/25mph, now the nearly 90 metric ton train was coming for it at twice that. At 2:24am, 1 minute and 40 seconds after it left the depot, C10 number 2887 obliterates the buffer stop at the end of Saltsjöbaden station, crosses through some bushes and over a footpath narrowly missing the ramp into a basement garage and finally drills itself into the side of a three story house 42m/138ft beyond where the buffer stop used to be. The edge of a balcony peels back the leading car’s roof before the rest of the car crashes through the kitchen wall, leaving a gaping hole in the wall of the house. Mister Grandinson, a resident of the upper floor of the building is woken up by a deafening crash of which he later said it made him think a plane had fallen into his yard, looking out his window he’s met by the sight of the bright blue train sticking out of the house’s ground floor. The residents of the affected flat are unharmed, but inside the train the cleaner is severely injured and pinned in the destroyed train.
Aftermath
The local police is on site a few minutes after the crash wakes up the surrounding residents, everyone in the struck house has to go outside into the snowy cold of the night. Responders fear that the building may collapse due to the damage caused by the train. Once it’s confirmed that the rail line’s power has been shut off responders enter the train and manage to rescue the trapped cleaner, she’s taken to the hospital in an unconscious state. Initially a rumor circulates that the cleaner “stole” the train/set it in motion on purpose, the assumption makes it all the way to the headlines in other countries. It’s circulated that she must’ve stolen a key somewhere, or had an accomplice, or maybe a driver forgot the key and it was a crime of opportunity. To quote one of the articles (itself quoting the spokesperson of Arriva): “It’s not very hard to drive a train once you get it started, you can just learn by watching or on the internet.” Due to the theory that setting the train in motion or even running it off the rails was a deliberate act the cleaner is formally arrested while still in the hospital, by the time she regains consciousness she has no memory of the night’s events.
While it is assumed that the cleaner is to blame for the accident investigators still look into other possibilities, retracing the train’s movements, talking to employees of the railway and its depot as well as coworkers of the cleaner. A few days after the accident the investigation drops the charges against the cleaner, claiming it’s no longer assumed that she stole the train. Instead, the railway employees had failed to adhere to standard protocols in several places. First of all, the train’s dead man’s switch (a device, usually pedal or button, the driver has to regularly press and release or release and press again to avoid an automatic stop) had been disabled at some point by placing an unspecified foreign object on the pedal to keep it pressed down. On the type of train involved in the accident this meant that the train’s control system assumed someone was in control. Secondly, the train had been parked up with the brakes released. Investigators found out that a shunting worker had chosen to park the train without applying the brakes as the depot’s system meant to keep brakes from freezing into place on parked trains was out of order. This defect had been known for over a month, but so far Arriva and the regional traffic ministry hadn’t managed to agree on who has to pay for the repair.
According to the shunting worker moving the train to a different track with a working ice prevention system would’ve taken too long and the cleaning wouldn’t have finished in time for the train to start service. Furthermore, the train had been shut off with the power-lever in the full-forward position, comparable to parking a car and placing a brick on the throttle pedal. With the key inserted (the driver had forgotten it there), the throttle-lever fully forward and the brakes released the only thing that kept the train from driving off were the open doors, as a safety-feature cut power to the motors if the doors were open. As the cleaner finished up cleaning the train she was to close the doors to the passenger compartment before leaving the train through the driver’s cab door. So, when she closed the passenger doors, the train registered that the train was “ready to depart” and had a driver present (the pressed down dead man’s pedal) and, subsequently, started driving.
As the signal box workers had already set the points for the first train of the day before going home for the night the train was directed onto the main line and quickly picked up speed. This too was a violation of company protocol, as points were supposed to never allow a runaway train (which this eventually was) to enter the main line. As it was the woman, who had no training in operating trains, found herself unable to stop the increasingly fast train, it’s assumed that the high stress of the situation caused her to miss the option of walking back through the passenger compartment and finding an emergency brake handle before the train reached the end of the line. Instead she retreated into the passenger compartment and crouched down low, likely knowing that things won’t end well. Less than 2 minutes after departing the depot the train crashed through the buffer stop at Saltsjöbaden station, mounted a small embankment, tore through some bushes and crossed a walkway, narrowly missing the entrance to an underground parking garage. Had the front of the train fallen into the parking garage entrance (which would’ve likely happened had the train reached the station on the other track) damage to the train may have been even worse (including a possible total loss of survival space). Loosing most of its roof on a recessed balcony right as it crashed into the wall of the house the inside of the driver’s cab was pushed through the train as the metal body crumpled and tore around it. 2 hours after the accident responders reached the woman, who had survived curled up in a tiny cavity in the destroyed forward half of the leading car.
After the accident Arriva changed their protocols and procedures to avoid a repetition of the accident, criticism that called for the Saltsjöbanan to finally receive a train control system, on the other hand, went unheard. Arriva had to pay 500 thousand Swedish Krona (approximately 53 thousand Euros/62 thousand USD) for professional negligence causing bodily injury, and a further 20 thousand Krona (1950€/2300USD) in damage pay to the cleaner for initially accusing her of stealing the train. Furthermore, they announced that an internal investigation was to be conducted regarding the premature release of information to the media as well as the disabling of the dead man’s switch. By September 2013 the leading car of the train was recovered from the building, after experts examined the structure it was repaired and residents were allowed to return if they wanted. The rear unit of the involved train was repaired and returned to service, the leading two cars were scrapped.
The buffer stop at the station was redesigned and rebuilt with stronger buffers integrated into a concrete wall backed up by soil, meant to now stop runaway trains even at top speed. A C6 metro train was adapted to the Saltsjöbanan to replace the destroyed unit and provide real life testing of the type on the line. Adding further converted C6 trains is considered the most practical option to allow a higher capacity on the line.
In May 2019 the Saltsjöbanan was finally upgraded to an automatic train control system, Siemens’ ZUB222c punctual train control now monitors the trains’ adherence to speed limits and signals.
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