Seven dead and more than 50 injured as tram overturns in Croydon

[EnterpriseSovereign]

The driver of a tram which derailed killing at least seven people and injuring dozens more has been arrested.

Emergency services were expected to continue work late into the evening at the scene near Sandilands tram stop in Croydon, south London.

Deputy Chief Constable Adrian Hanstock said: "We expect to be at the scene for at least the next 24 hours, continuing searches and carrying out forensic examinations in support of the investigation into the circumstances, and in order to provide a report for the Coroner.

"Tomorrow, we will assess how and when it is appropriate to recover the tram and remove it from the tracks."

More than 50 people were injured when the crowded rush-hour tram tipped on to its side next to an underpass near the stop shortly after 6.10am on Wednesday.

A spokeswoman for London Ambulance Service confirmed eight people have serious or life-threatening injuries.



The tram had been travelling at a "significantly higher speed than is permitted" when it derailed, according to the independent Rail Accident Investigation Branch said.

At least five people were trapped and had to be freed by rescuers, with the London Fire Brigade saying earlier they had sent eight appliances and more than 70 firefighters to the scene in Addiscombe Road.

Prime Minister Theresa May said her "thoughts and prayers are with all of those who have affected by this terrible incident on the tram in Croydon".

Full article here.

Unfortunate timing, any other day this would have been front page news. Though to be fair at least one paper (not sure which) did give this its due.

[SpottedKitty]

The BBC report I read earlier quoted a local witness saying the trams had been frequently taking that bend at high speed. And they don't have speed limiters like the ones fitted to actual trains. This is looking like that case a few years back of a (Spanish?) high speed train derailing on a curve of conventional track because it was going way too fast.

Found it; here's the wiki page.

I wonder why there wasn't a speed limiter — was it just that no-one thought it would be needed?

[Sea Skimmer]

Automatic train control systems and even simpler autobrakes eat at up money and make service slower is why. A bus does not have a speed limiting system that prevents it from rolling over, or falling into the OCEAN for that matter, why should a tram? If you want zero risk in life go hide in an attic maybe?

The 2013 Spanish train disaster as far different, for one thing its a basic reality that far more people are on board a real train, and high speed rail requires some kind of automatic control because its simply impossible for the driver to see line side signals. The Spanish track was brand new and simply built in a negligent manner. They did not install any kind of automatic speed control for the deathcurve, even though that curve marked the transition from a long chunk of 200kph track to a 50kph track where the high speed route joins an existing system. That was just unreasonable, done for cost cutting on what was at the time a brand newline, and changed before the line reopened again for high speed service.

We had 8 people killed near where I live in Phily in 2015 from an excessive speed derailment, no auto break had been installed because simply the curve was well known and had had no major accident since 1943 when far more people died, and because the US congress mandated a far more complex positive train control system...which is an on going nightmare to get installed and qualified. PTC is now operational on m y commuter line and we can't seem to ever go a single trip without tripping some kind of auto brake feature to bring the train to a pointless halt.

[EnterpriseSovereign]

From what I've read, buses like double deckers are designed with a low centre of gravity so that they're difficult to roll (My teacher once said that when she went to school the older kids on the top deck would run to one side when the bus took a turn to scare the shit out of the first years).

From the Wiki:

Public service vehicles often have a legislated top speed. Scheduled coach services in the United kingdom (and also bus services) are limited to either 65 mph or 100 km/h (62 mph) depending on their age (newer coaches have the lower speed version installed, in line with harmonised EU regulations), though for city buses the use of limiters is to satisfy regulatory requirements, as many city buses cannot achieve these speeds even on an open roadway.

It would seem that trams or trains aren't subjected to similar regulations.

I remember seeing the Santiago crash on the news, the CCTV footage next to the track showing the oncoming train was some scary shit when you watch it at full speed.

According to one of the survivors, the tram was taking that particular turn far faster than it normally does.

[Starglider]

This is the line I used to commute into London on every morning. Could have been in the crash if we hadn't moved house three years ago. Anyway, the speed limit on that bend is 14 MPH. This is not a problem that could be solved with any reasonable setting on a simple speed limiter; the tram has to do 40 MPH just to keep up with traffic on some sections. The driver is claiming he blacked out, if true then should have had a better (or any) dead man's switch.

[SpottedKitty]

The driver is claiming he blacked out, if true then should have had a better (or any) dead man's switch.

I haven't come across the "blacking out" claim anywhere yet. And in one report earlier today, I saw the dead man switch seems to be a thumb button on the throttle lever. Anyone know how that compares with other types? Is it particularly vulnerable to being bypassed, or prone to give the driver a "numb thumb"?

[Sea Skimmer]

Trolleycars in the US generally use a foot peddle instead of a console mounted positional throttle as on a train as a form of dead mans switch. Is not ideal, but no worse then any bus on the road, and makes for similar training to bus drivers. Thumb buttons have existed for railway stuff for a long time, so have various console buttons, they are not ideal because they become very annoying and people begin using DEFEAT DEVICES against them.

This has also been a problem with foot peddle controls before, people actually putting weights on the peddles to reduce the resistance to keep it depressed.

It is worth considering that even such dead mans switches usually have some kind of built in delay, so that they are not so troublesome the operators go on strike over it. The 2015 train in the Amtrac derailment hit a speed unsafe for the curve only about 60 seconds before derailing, though it had long exceeded the regulation speed, which was set for passenger comfort. Basically all paths lead towards wanting positive control of the train if you want to rule out operator errors, PTC was not thought up on a whim, its a sum total of all past crash experiences everywhere. But that's very expensive to implement and upkeep, and it does nothing to reduce grade crossing accidents or derailments from right of way maintenance failures, which tend to be more common then outright train wrecks. So the appeal of highly automating a tram system is kind of low, since the damn traffic accident issue so tremendously higher then heavy rail.

PTC style controls would become much cheaper if one was willing to build a system 100% reliant on GPS signals, but present GPS quality is not sufficiently precise for this purpose, it couldn't tell which track a train was on with 2 side by side tracks with reliability. GPS Block III will have that kind of accuracy in the future, will Galileo. Right now GPS can only augment a PTC system that also includes a billion integrated track side sensors. Also this means if say, North Korea sets off several nukes in space, your railway control system might be FUBAR for years.