Light rail is worse than miniture railway?

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Nick W

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Personally I can't see any flaws, assuming computers are powerful enough.

Naturally this wasn't around when a lots of light rial was built, but now that it is around we should use it.
 

Nick

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I've just had a scan through it, surely this scheme for a 25mph mini railway couldn't work in an urban climate as a people mover like say in Liverpool?
 

Nick W

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Nick said:
I've just had a scan through it, surely this scheme for a 25mph mini railway couldn't work in an urban climate as a people mover like say in Liverpool?
Fistly it's pointing out that 25mph is faster than most trams which average at 20mph or so, and also see the last page of it.
 

tramboy

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Interesting idea, the one thing thought that you'd lack would be the capacity. It looks like a scheme similar to the ULTRA lightrail proposed for Cardiff a while back. It could also be costly to install if things go wrong...and remember that miniature railways are slow speed. Light rail tends to get to 50kph (30mph) between most stops, apart from those in pedestrian areas, where 25kph is still the max. This thing would still be subject to the same rules and regs, so the speed bonuses wouldn't be noticed...as when LR is out of urban areas, it makes up time (80kph), and this would be limited to a slower maximum speed. A good thought for mostly urban american cities...where you get 19km of line all onstreet running, but not for Britain, where we are less built up...

Cheers

Dave
 

Nick W

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tramboy said:
Interesting idea, the one thing thought that you'd lack would be the capacity. It looks like a scheme similar to the ULTRA lightrail proposed for Cardiff a while back. It could also be costly to install if things go wrong...and remember that miniature railways are slow speed. Light rail tends to get to 50kph (30mph) between most stops, apart from those in pedestrian areas, where 25kph is still the max. This thing would still be subject to the same rules and regs, so the speed bonuses wouldn't be noticed...as when LR is out of urban areas, it makes up time (80kph), and this would be limited to a slower maximum speed. A good thought for mostly urban american cities...where you get 19km of line all onstreet running, but not for Britain, where we are less built up...

Cheers

Dave
I think that's pointing out that light rail with stops averages at 20mph whereas the kiddy rail would be 25mph non stop.

And with 2 people every 2 seconds potentiall kiddy rail could ahv emore capacity than light rail :)

Anyway if you look at step 11: "Does anyone want to travel at 25mph, the point it's trying to make is that instead of light rail we should have:

 

evil_hippo

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What worries me about cardiff-style systems is the security aspect- You could join someone who is on their own in oen of the little cars and do pretty much what you liked.
 

tramboy

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Kiddy rail...I'll point out that the name may denote a few sizing issues. Also, it won't be 25mph all the way...as with certain portions leaving and joining the main guideway, there will always be one to slow down...which means that, if they are running in such close formation, the ones behind will slow down, etc, etc.

Also, as Zoltan points out, light rail is a lot safer, as there is always someone in a LRV, but not in an Ultra pod.

Regards

Dave
 

Nick W

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tramboy said:
Kiddy rail...I'll point out that the name may denote a few sizing issues. Also, it won't be 25mph all the way...as with certain portions leaving and joining the main guideway, there will always be one to slow down...which means that, if they are running in such close formation, the ones behind will slow down, etc, etc.
Yes on a motorway everytime a car comes off at a slipway the ones behind slow down....

Also, as Zoltan points out, light rail is a lot safer, as there is always someone in a LRV, but not in an Ultra pod.
Well DLR is probably safter but systems that mix with cars won't be as safe.
The skytran pods can stop from 100mph in 2 secs if emergency brake is used...
 

tramboy

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2secs from 100mph? One assumes that is a typo, otherwise there will be a lot of flattened people in these pods should an emergency occur.

Actually, people do slow down to leave motoroways...generally because it involves taking the inside lane to leave, and so if there is any vehicle in this, you must run at the speed of that vehicle until you leave the carriageway.

Trams and Trains remember, all have points. Now, unless you want derailments, which cars can't do, it tends to be a good idea to slow down for these, and also for passenger comfort levels.

Systems that mix with cars have not yet had any sort of pile up in the UK. There was the Roe case in Sheffield (that is nothing to do with Supertram though) and you will be a lot safer inside the tram than in the car outside, or on this "kiddy rail" thing.

Regards

Dave
 

Nick W

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6G ie 100mph to 0 in 2 secs is surviveable if not prolonged, and is much better than crashing into the vehical in front like cars do...
 

yorkie

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How will points work here? Let's face it, the system is totally flawed and is a joke!

So you have loads of vehicles really close together, and one wants to take the diverging route. Do the points suddenly change in front of it? If it's really that close to the preceding vehicle you would need the points to be quick at changing. What if the points fail? Surely the route would be set to danger until the points are proven to have switched, but that would mean a lot of slowing down to take a diverging route.

This has all the technical disadvantages of car travel (lots of small vehicles competing for space) along with the disadvantages of light rail (limited to going where the rails take you).

The idea that loads of individual vehicles are cheaper to buy, run and maintain than much fewer proper size vehicles is clearly a joke.

I think this site is a deliberate attempt to fool people and they laugh at the people they've fooled who actually believe it!!! :D
 

Nick W

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yorkie said:
How will points work here? Let's face it, the system is totally flawed and is a joke!

So you have loads of vehicles really close together, and one wants to take the diverging route. Do the points suddenly change in front of it? If it's really that close to the preceding vehicle you would need the points to be quick at changing. What if the points fail? Surely the route would be set to danger until the points are proven to have switched, but that would mean a lot of slowing down to take a diverging route.
I'm sure it just has fast changing points. Even ones on the current railway take only 2 secs or so...

This has all the technical disadvantages of car travel (lots of small vehicles competing for space) along with the disadvantages of light rail (limited to going where the rails take you).

The idea that loads of individual vehicles are cheaper to buy, run and maintain than much fewer proper size vehicles is clearly a joke.

I think this site is a deliberate attempt to fool people and they laugh at the people they've fooled who actually believe it!!! :D
I doubt it. If we could do the DLR 15 years ago we can do this now.
 

Tomnick

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Yes, but the protecting signal can't be cleared for a route across any set of points until they've detected normal/reverse as appropriate. So any vehicle approaching said set of points must be in a position to stop short (i.e. slowing down! - and this ridiculous thought of stopping from 100mph in 2 seconds or whatever it is doesn't count as service braking!) until detection is achieved. Yet another flaw in the plan?
 

yorkie

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Nick W said:
I'm sure it just has fast changing points. Even ones on the current railway take only 2 secs or so...
Oh no they don't!

Bear in mind the preceding vehicle must be proven to be clear of the points, then the points change, then the route has to be proven to be set for the correct route, then the route can clear. In the mean time the route is set to danger.

Think about it.

Nick W said:
I doubt it. If we could do the DLR 15 years ago we can do this now.
But the DLR is the opposite of what they are suggesting. Consider how many people can fit in a packed 4-car DLR train, and consider the requirement for all of them to have their own seperate vehicle. It really makes no sense at all!

Tomnick said:
Yes, but the protecting signal can't be cleared for a route across any set of points until they've detected normal/reverse as appropriate. So any vehicle approaching said set of points must be in a position to stop short (i.e. slowing down! - and this ridiculous thought of stopping from 100mph in 2 seconds or whatever it is doesn't count as service braking!) until detection is achieved. Yet another flaw in the plan?
Well said! IF this is a serious suggestion then this problem clearly has not occured to them.
 

Nick W

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Tomnick said:
Yes, but the protecting signal can't be cleared for a route across any set of points until they've detected normal/reverse as appropriate. So any vehicle approaching said set of points must be in a position to stop short (i.e. slowing down! - and this ridiculous thought of stopping from 100mph in 2 seconds or whatever it is doesn't count as service braking!) until detection is achieved. Yet another flaw in the plan?
This system is robotic ie no human driver.

No human driver = no need for a protecting signal.

this ridiculous thought of stopping from 100mph in 2 seconds or whatever it is doesn't count as service braking!
I bet the people now in heaven from Ladbroke Grove wished that the HST could brake from 100mph in 2 seconds.
 

Tomnick

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So you're saying we should allow these vehicles to speed towards a set of points that may or may not be correctly detected by the time it gets there? And what if the points don't detect? Whether there's a physical signal or not - you can't 'assume' that the points will change, or you're going to end up with a bit of a mess to deal with!

As for stopping from 100mph in such a ridiculously short time - unless everyone's properly restrained (and I mean properly! - not just a simple seatbelt), they're going to go for a very short high speed trip into the front windscreen...
 

tramboy

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I point out that the DLR, being as it is with no human driver, still has signals just in case the automation system fails and the train captain needs to take over. Full automation is, as yet in this country, limited to small people movers that don't travel long distances and are fully segregated and monitored, such as those at airports.

The plan for going over points has already been pointed out to be flawed, and I'll re-iterate what I said earlier, whereby if you go from 100mph-0mph in 2 seconds, you will end up squashed against the thing in front of you. If that is the windscreen, and you hit it with a force of roughly 6G, you will go through it, and end up on the track in front/hitting the vehicle in front (if it's that close) and quite probably suffering from a severe case of deadness.

Regards

Dave
 

yorkie

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Nick W said:
No human driver = no need for a protecting signal.
Regardless of whether the driver is a human or a computer, junctions need protection if they are not set correctly.

I've not read about the DLR in detail, but I have seen a programme about it, it uses moving blocks, rather than conventional block sections with fixed signals. But that doesn't change the principle.

Are you saying that trains should hurtle towards points without any regard for whether they are set correctly and then you just hope for the best? Hmm. If you're lucky then you get your 2 second (or whatever laughable figure they came up with) headways and high speed running. If you're unlucky then you end up dead.
 

Nick W

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Ok this is talking about skytran not kiddy rail.... if you read the last kiddy rail page you would see it linked to skytran as 100mph beats 25mph.

I'm guessing the points probably change instantly with a solenoid or something that only operates in 2 modes.

Either way the system works with a radar to detect how far in front the next pod is.

I'm sure the system cannot be less safe than driving....
 

yorkie

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Nick W said:
I'm guessing the points probably change instantly with a solenoid or something that only operates in 2 modes.

Either way the system works with a radar to detect how far in front the next pod is.
Even if was "instant", the system works on the basis of a tiny headway between vehicles, but such a tiny headway cannot possibly be maintained. If the switches are high speed, then they will be long, and consider that the rear of the preceding vehicle must be completely clear of the points before they can change, and the route cannot be proven until the points have changed and detected as having done so. In the mean time the route is unavailable and the 'pod' will have to be slowing down considerably.

Face facts: the headways they propose are ridiculously unobtainable.

Nick W said:
I'm sure the system cannot be less safe than driving....
When you say "driving", do you mean "driving a car"?

If so my answer is; No but the media, government etc appear to accept road crashes as a fact of life, but do not accept rail crashes. Even if it was twice as safe it would not be 'safe enough'.
 

Nick W

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Good point

I think the best use for this system would be as a feeder into a bigger station with 4tph or better service.
 
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I think that whole article should be taken with a pinch of salt. It is obviously a put down by someone in, or connected with, the motor industry. Possibly with Goverment connivance. The oil and automobile industry in America will do literally ANYTHING to protect ther positions.

Take the example of the red streetcars that used to run in Los Angleles. An efficient and well run substantial network of routes that was of real benefit to the citizens. The motor industry bought the whole caboodle and ran it down and closed it. Then when it was realised that the resultant air pollution was a danger to the residents they built some new light rain lines to try and correct the mistake. In doing that no attempt was made to restrict the cause of the pollution, the car and truck.

The trouble with the transport industry today is that their forward thinking is too short. They can only see short term profit and not long term benefit.

Sorry for the late post but having only just really read posts on this forum I had not seen it previously
 

yorkie

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Yeah, it could even be a spoof site, set up as a joke to see how many people believed it.

They'd probably laugh if they realised that Nick W actually believed it could happen :D Sorry Nick ;)

On the other hand, if they are serious, then yes their maths are very wrong, and they probably need their heads examining.
 

kettlefan

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the main flaw with this as I see it is this. I drive 7 1/4" and 5", not very big and certainly not big enough for the idea put forward on this thread. Now the maximum speed we are allowed to drive the 7 1/4" on the GCR is 10mph. We really rarely get above 6, although the duchess did 8 once. This really is the maximum safe speed for that gauge, so we go up to 10 1/4", ok you can go faster there, but really ownly safely up to 10/15 mph. by this time your upto 15" gauge, and depending on who you listen to this gauge is considered "light rail" already! For example the RHDR is described as a miniature railway by some, but the Ravenglass railway is quite definitely narrow gauge, it pulled service freight trains in its heyday for pities sake! By the time you get to a safe enough gauge, you have a light railway already, may as well go 2 foot just to be sure!
 
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