From my experience as a passenger on the Croydon Tramlink sitting behind the driver, they use a joystick controller for the speed of the train. I assume that this would return to a nominal position like a dead mans handle, if let go by an incapacitated driver. Whether it would also put the brakes on, I do not know.

Neither do I but that is an interesting question.

Build the factories where there is a need for the goods .....

The factories are in China, the goods have already gone over the Pacific Ocean.

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With no crews, what happens if a train had a trainline or mainline burst in a tunnel...

From my experience as a passenger on the Croydon Tramlink sitting behind the driver, they use a joystick controller for the speed of the train. I assume that this would return to a nominal position like a dead mans handle, if let go by an incapacitated driver. Whether it would also put the brakes on, I do not know.

Neither do I but that is an interesting question.

Your Underground trains still use air (or vacuum?) brakes? I can't speak for every city in North America, but in Chicago L trains use a combination of dynamic (and in the very newest cars, regenerative to the supply) brakes for major deceleration and electrically controlled, spring actuated friction brakes in the axles. This was first used on the L in the 1950s, having been adopted (by dint of reusing the parts from dismantled cars) from streetcars designed in the 1930s. I can say from personal experience that all such cars do go into emergency if the operator lets go of the controller in any power setting or even coast. I can also say that the L's last cars with air brakes, from the 1920s, merely cut off power if you let go.

(On the other hand, Illinois Terminal 415, sort of an overgrown streetcar / small interurban also from the 20s, will go into emergency if you aren't holding down the controller anytime the air brakes are released.)

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David
Sitting on my butt while others boldly go,
Waiting for a message from a small furry creature from Alpha Centauri.

The train in question was not an underground train, but a mixed segregated and street running tram. It has three braking systems, air, electric and hydraulic. Being a single side-stick controller makes the use of a deadman's handle difficult, so like many modern European trains and trams it uses a treadle that, in the event of holding a constant speed, or braking effort, both of which require the stick to be held in one position, has to be "kicked" when a "bell" goes off. One advantage of this sort of "I'm alive" detection is that it takes a positive action to kick the treadle, whereas the deadman's handle can be beaten if the driver collapses in such a way as to hold the handle in a valid position.



Going back to Richard's comment about using the passenger information system to locate the tram's position and so be able to interact with the train controls. While this sounds a good idea these systems are very simple and crude - On my journey to work I regularly see these displays giving the wrong station, or heading off in the wrong route, or being blank, none of which is of much use when trying to correctly locate the train and what speed it should be doing.

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Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?

Going back to Richard's comment about using the passenger information system to locate the tram's position and so be able to interact with the train controls. While this sounds a good idea these systems are very simple and crude - On my journey to work I regularly see these displays giving the wrong station, or heading off in the wrong route, or being blank, none of which is of much use when trying to correctly locate the train and what speed it should be doing.

Then the system is not very good. Probably not enough people working on keeping the programming up to date.

North American Positive Train Control uses GPS to determine a train's position, along with logic in the software to tell it the train did not suddenly jump to the next track when the GPS inaccuracy says it did.

In the Chicago area, Metra uses GPS to trigger the automated on-train announcements of what the next stop is, but it would be nice if the conductor could turn it off when the train is full and runs express to downtown.

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David
Sitting on my butt while others boldly go,
Waiting for a message from a small furry creature from Alpha Centauri.

The Passenger Information System is only intended to give INFORMATION to the passengers, and not do any train control. This has absolutely NOTHING to do with the software maintenance activities you talk about.

Systems like ERTMS, PTC, ATC and so on are designed to offer varying degrees of train control, thus have a far better "understanding" of where the train is , how fast it is going, and how fast it should be going.

To "bend" a PIS system into some form of train control system would involve a lot of re-engineering of the hardware on both the tram and the infrastructure and cost a lot of money. Indeed it would probably be less expensive to buy a new train control system than, wit all the required interfaces built into it than try to modify the PIS to do something it was never intended to do.

BTW. Using GPS as a trigger for anything "safety related" is totally crass - what happens if the USG decides to turn SA off - you suddenly loose the precision that we have grown used to, the same happens when the satellite coverage is poor, either due to local topography, or one of the regular "low satellite availability" events.

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Bob Smith
Member of Seti PIPPS (Pluto is a Planet Protest Society)
Somewhere in the (un)known Universe?

Your Underground trains still use air (or vacuum?) brakes? I can't speak for every city in North America, but in Chicago L trains use a combination of dynamic (and in the very newest cars, regenerative to the supply) brakes for major deceleration and electrically controlled, spring actuated friction brakes in the axles.

Did some checking. The last rolling stock to use that system has been replaced with that replacement being completed by Dec 2016.

Have to say that the Bombardier "Movia" family of metro trains are a great improvement over previous LU rolling stock.

The Passenger Information System is only intended to give INFORMATION to the passengers, and not do any train control. This has absolutely NOTHING to do with the software maintenance activities you talk about.

My maintenance comment referred only to the accuracy of the info system for its own sake. On the contrary, it would be a better idea to have the info system be an offshoot of the safety system.

BTW. Using GPS as a trigger for anything "safety related" is totally crass - what happens if the USG decides to turn SA off - you suddenly loose the precision that we have grown used to, the same happens when the satellite coverage is poor, either due to local topography, or one of the regular "low satellite availability" events.

I don't know, but I assume that if PTC loses its GPS fix, it reverts to a "safe mode" of some sort.

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David
Sitting on my butt while others boldly go,
Waiting for a message from a small furry creature from Alpha Centauri.

BTW. Using GPS as a trigger for anything "safety related" is totally crass - what happens if the USG decides to turn SA off - you suddenly loose the precision that we have grown used to, the same happens when the satellite coverage is poor, either due to local topography, or one of the regular "low satellite availability" events.

Switch to Glonass of course.

If HGV in the USA have a GPS with sat transponder that can report back to dispatch near real time information obviously it can be done for rail. Also very possible is linking the signal transponders to transmit serial numbers both ways so the database in the train knows which signal it just passed and the dispatch office is notified that train XYZ just passed. GPS can fill in speed information on long blocks to better predict arrival times or for those areas which do not connect back to the dispatch office.

Essentially all of this is done in the aviation industry and in three dimensions.

Oh as to GPS off, it isn't going to happen unless the NUKES are already in the air. FAA is now allowing pure GPS flight operations. Having airliners lost wandering around isn't in the cards.

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Yep both part of Bombardier's "Movia" family :-) About time too as the A60's & A62's were getting a bit long in the tooth.

If the max speeds for any section were programmed in, it ought to be relatively simple to sound a warning bell in the cab for an over speed.

That implies the system knows the weather , track conditions etc , doubt any system used by TFL is that "clever"

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Life is what you make of it :-)

When i'm good i'm very good , but when i'm bad i'm shi#eloads better ;-) In't I " buttercups " p.m.s.l at authoritie !!;-)

The Chicago Transit Authority's signal system, as I believe I've mentioned before, regulates train speeds in slow spots by keeping the next signal red until it senses that the approaching train is very close and going the proper speed. It also sends the maximum allowable speed in any given piece of track to the train, where it is displayed alongside the actual speed. All of this has been done since long before there were satellites, let alone GPS satellites. I'm not sure what the penalty is for overspeed, but passing a red signal trips something under the car which has to be reset manually, and a good talking to by the supervisor (at least; maybe suspension).

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David
Sitting on my butt while others boldly go,
Waiting for a message from a small furry creature from Alpha Centauri.

Not just South London but transport safety overall.

Whilst I would prefer to wait for the RAIB (who I have the greatest respect for) to make a statement.

Remember the tram system is "light rail" and was designed to be more like "busses on rails" There are very few signals none at all on the "off road sections" as trams are driven like busses, i.e line of sight and you can often see trams running one behind another at stops with only bus like distance between.

There are signals at some junctions to show the way the points are set, and signals where the tram has to cross a road. These consist of a horizontal line made up of 5 white led's for stop, which changes to a vertical line when the tram can proceed. The signals are obviously linked into the road traffic signals.

I do not believe the system was ever designed to deal with the sort of junction that exists at Sandilands. The 50 mph to 12 mph change seems to be too severe and perhaps the preceding section needs a lower limit.

There are reports of over speed here before.

As I said I wait with interest for the RAIB report and recommendations.

There are signals at some junctions to show the way the points are set, and signals where the tram has to cross a road. These consist of a horizontal line made up of 5 white led's for stop, which changes to a vertical line when the tram can proceed. The signals are obviously linked into the road traffic signals.

Bernie is correct about the led displays, but I am not sure they are linked into the road traffic signals. Every tram I ever went on yhey vigorously rang bells at every road crossing. but possibly for the pedestrians.

I can't begin to imagine the huge sum for a lawsuit if the signal displayed green/go for cross traffic and safe to pass for the tram at the same time. Of course it is linked.

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There are signals at some junctions to show the way the points are set, and signals where the tram has to cross a road. These consist of a horizontal line made up of 5 white led's for stop, which changes to a vertical line when the tram can proceed. The signals are obviously linked into the road traffic signals.

Bernie is correct about the led displays, but I am not sure they are linked into the road traffic signals. Every tram I ever went on yhey vigorously rang bells at every road crossing. but possibly for the pedestrians.

I can't begin to imagine the huge sum for a lawsuit if the signal displayed green/go for cross traffic and safe to pass for the tram at the same time. Of course it is linked.

The 'white bar' or 'white dot' tram signals are part of the uniform traffic signal specification throughout the United Kingdom - see p31 of know your traffic signs (PDF). I've seen them in Manchester and Edinburgh: we don't have trams in Bradford any more, but the same signage is used on our dedicated guided busways. And yes, they are very definitely integrated into the urban traffic control signals for motor vehicles, cycles, and pedestrians.

Anyone wishing to read the RAIB report go

HERE

http://www.foxnews.com/auto/2016/11/16/oklahoma-speeder-caught-at-208-mph.html

An Oklahoma man was arrested on Saturday after leading police on a 208 mph chase.

Nineteen-year-old Hector Fraire first tripped a radar gun doing 84 mph on the Kilpatrick Turnpike in Oklahoma City, before speeding away as police tried to pull him over.

According to the Oklahoma Highway Patrol, Fraire’s heavily modified 2011 Ford Mustang was then clocked doing 176 mph and 208 mph, and he tried to elude the chase vehicle by turning off his headlights and brake lights.

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Trawling through youtube and saw this https://www.youtube.com/watch?v=VH-uwNsyzf0

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Old enough to know better(but)still young enough not to care

Saw this on a site that puts up finds of the month. not linking to there as this has to be family friendly. but it's on YouTube as well.
Don't Forget Your Parking Brake

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