Luas Let Down

MaceFace

Does anyone have any idea about the Luas Red Line.
It was supposed to be running every 5 mins during peak times and also have dedicated Heuston-Connolly runs.

None of this appears to be the case, and I wondered if anyone knew if it is shelved for good, or if it is still in the plans.

Have to say that it really isn't that great a thing as the bus can often beat it on the run between the two stations, and considering the Luas has no traffic to deal with and controls the lights, something must be wrong!

enterprise

I can't remember where but I did hear a 5 minute service should be launched in a few weeks.

The trams do not control the traffic lights. The traffic lights are controlled by the DCC's SCATS traffic control system and the trams request the signal as it approaches them. This allocates the level of priority to the tram as it approches the signal. If the signal clears, while moving the tram is getting high priority, if it gets stopped the priority is at a lower level.

LUAS still beats the bus in the rush hour however!

MaceFace

It will be better when it goes to 5 mins, but I have been on the bus and it has been better on many occassions.
The problem with the LUAS is that it slows to a crawl in so many places and they leave the doors open for much longer than they should.
At museum this morning, they were open for more than 30secs and about 2/3 people got off in the first 5 seconds. I was looking in the camera the driver sees and there was no one else.
I think they need to get some training in customer service and getting poeple there as quick as they can (and of course safely).

D8 boy

I can see 2 problems which may be preventing operation of a 5-minute interval service at the moment:
1 - One of the 30-metre trams from the Red Line is still in service on the Green Line in part replacement for the 2 trams damaged in the collision at Stephen's Green last year, so the ReD line is down one tram;
2 - Last I heard was that the running time was still several minutes over the planned 43 minutes which means that more trams are needed to run the service.
I guess the first issue is just a matter of time before both damaged trams are returned to service. The slow running may be more difficult to sort out and may mean the 5 minute service cannot be operated without extra vehicles.
Anyone else know anything ??

murphaph

There's no shortage of trams in the Red Cow depot. That is not the reason anyway. It's other stuff like interfacing with traffic. Red Line is wholly inadequate for what it's supposed to achieve.

enterprise

You could still keep 3002 on the green line when a 5 min service is introduced on the red line if the Connolly / Heuston services weren't introduced.

A full service requirement would be 24 trams, there are 26 3000 series tram, incl 3002 on the green line.

One of trams damaged in the september accident has been returned to service, bascially they made one good tram out of two (used the two ends of each tram that weren't badly damaged). Therefore one end carries the number 4002 while the other end carries 4012. It's know as "Frankenstein" by Connex staff while 3002 is known as the "Baby"

Bee

Folks,

The problem with the Luas is that the entire concept of the Luas is a total farce and rip off of tax payers money.

Dublin needed/needs an underground metro not a traffic congestion creating waste of space whose only function ha been to divert bus users onto it. When it runs that is!

Bee

BrianD

Clearly not the case BEE! Trams are suited to Dublin but a two line system is only part of the solution.

Heuston-Connolly runs have never been promised though some provision has been made for them. I spoke to a Luas person some months ago and they were then inly starting to investigate the possibilities of providing such a service and what the implications would be - power consumption etc.

Metrobest

Luas is a tale of two halves. The Green Line is a great success because of its clear, direct route; most of the stations could easily be upgraded to metro-standard. Getting the Red line up to a five-minute fequency could prove difficult. The line from James's-Connolly is hampered by a bad track trajectory, interaction with road traffic and junctions at which it has no priority under SCATS. The Heuston-Connolly section should have been underground from day one.

MarkoP11

Luas to Tallaght was and is a mess, it has neither the capacity nor journey time to be practical, 50 odd minutes is just plain crazy. The 3rd platform at Heuston is not explicity for Heuston Connolly its a usefull location to dump a failed tram, I've seen the documentation which says nothing of a direct shuttle service.

If we go back in time to 1975 we find the DRRTS, Dublin rail rapid transit study which proposed a Dart line from Tallaght to Clondalkin then Heuston through a tunnel under the quays and connecting to the current Dart line at Fairview. Even in 1975 they where talking of a high capacity heavy rail solution, that was before the Square, Tallaht hospital and everything else.

Dart to Tallaght was phase 2 it got dropped in 1987 by government (WRC is to be phased hmmm), if we got that we would be in no where near the mess we are in now

It is clear to see the Green line should have been some kind of fully segregated heavy rail style setup from day one

antoinolachtnai

It all has to do with journey time. If the journey time is 10 percent longer than expected, then the frequency is going to be 10 percent lower.

If the journey times become unreliable (meaning that journey time varies a lot) then it gets tricky to keep a consistent interval between trains. Once the interval becomes a little inconsistent, it screws everything up, because the trains get delayed by larger numbers of people boarding and leaving, and as a result begin to run slower.


This looks like what is happening on the Luas. I'm not a regular user, but the times I have been on, the gap between trains is sometimes ok, and sometimes gets very long.

If you have the latter problem, then adding more trains won't necessarily help that much.

In terms of what is causing the problem, there seems to me to be a problem with the way Luas is interoperating with rubber-wheeled traffic along the quays. To make it work, the tram has to move along in sync with the 'wave' of traffic on the quays. It doesn't, and that means it is constantly stopping and starting.

At the same time, the traffic seems to me to to be brought to a halt around Gardiner St occasionally for no good reason, when there are no trams around. It looks to me like there are 'phantom trams' haunting the system. Again, this is just from occasional observations.

The key to sorting these issues out are simplified operations, better communications and increased discipline.

This is all from my own observations and my own research and experience with public transport operations. I haven't seen any metrics, but I'd be interested to put some numbers to the theory.

Metrobest

antoinolachtnai wrote:

At the same time, the traffic seems to me to to be brought to a halt around Gardiner St occasionally for no good reason, when there are no trams around. It looks to me like there are 'phantom trams' haunting the system. Again, this is just from occasional observations.

The key to sorting these issues out are simplified operations, better communications and increased discipline. .

You're right. AFAIK, at this junction you mention, the Luas has no priority over road traffic, so it must wait for the phase of lights to change in its favour. What complicates it further is that the tram drivers are allowed dictate their own priority at other junctions, so it makes it difficult to get 'smooth' frequencies to the service.

enterprise

Tram drivers can't dictate their own priority.The SCATS system controlls the whole lot and gives different levels of priority to the tram depending on its schedule.

Metrobest

enterprise wrote:

Tram drivers can't dictate their own priority.The SCATS system controlls the whole lot and gives different levels of priority to the tram depending on its schedule.

No. Drivers can set a priority of high, low or medium depending on their schedule; the only exceptions being junctions such as Beresford Place where the lights are in set sequences and trams must wait their turn like cars.

MarkoP11

Metrobest wrote:

No. Drivers can set a priority of high, low or medium depending on their schedule; the only exceptions being junctions such as Beresford Place where the lights are in set sequences and trams must wait their turn like cars.

SCATS has no idea of the tram schedule.

The drivers console on a Luas tram has a button marked with RTS (not 100% about the exact lable) on the right side. This is the request (to start) button which the driver pushes to trigger the lights if required its a lot like the pedestrian lights button pushing it over and over again has no difference.

If the priority lay with the driver of the tram surely we would not be having the hassle we are having

antoinolachtnai

If the driver had much priority, a single tram would trip up the movement of traffic across all the bridges in the city, wouldn't it? The SCATS does a very delicate dance to keep traffic moving smoothly along the quays. Interrupting the flow might be ok off peak, but at peak times traffic might back up across the bridges in a fairly awkward way. And once the quays get screwed up in Dublin, everything else tends to go haywire too.

I think that a little judicious moving around of the platforms (to make sure the platforms were always on the right side of the junctions) might contribute to sorting out some of the problems.

South of Heuston is a different story of course. I don't know that part of the line well enough to give an opinion.

Metrobest

At certain junctions between Heuston and Connolly, when a tram wishes to go through a junction without delay, the DCC's traffic control unit computer receives a 'hurry call' and lights go red for all other road users, allowing the tram pass quickly. The lights then revert to their regular sequence.

At other junctions, the Luas has the same priority as cars and buses, and must wait its turn in the regular light sequence.

Stix

1. The Luas should be given priority at every junction. The lights should be changed before it even reaches the junction so there is no slowing down.

2. It should stop at every station. Half the time no one gets on or off.

3. It would have made more sense to run the Luas down the centre off the Liffey by building a line supported by struts from the Liffey Walls.

PLANNING PLANNING PLANNING

Metrobest

Exactly. And here's the even more depressing bit: if the frequency goes to 1 tram every five minutes, the Red Luas will have to be given lower priority at junctions where it currently 'enjoys' high priority. Some people say a Luas to the airport would be a better option than a metro; the experience of the Red Luas suggests otherwise. No amount of creative planning can allow onstreet trams reach the kind of frequency and capacity you get from a metro.

MartMax

speaking of myself! most of pedestrians never really care, they cross at all times, not watching if trams r coming, even just don't care ie. "trams won't hurt me!"... that keeps the tram moving slow... the tram drivers like "oh mine, there are people on my way, they gonna hit us!" bell rings and tram slows down... :cool:

antoinolachtnai

Stix wrote:

2. It should stop at every station. Half the time no one gets on or off.

You mean it shouldn't stop? This doesn't really work with trams unless you have an express line. The tram behind catches up with the tram ahead and can't get past it, so you get bunching.

3. It would have made more sense to run the Luas down the centre off the Liffey by building a line supported by struts from the Liffey Walls.

Aside from the engineering challenges of supporting the weight of a tram and tracks on an old wall, how would the Luas get past the road bridges on the Liffey?