Bus Controllers

KD345

Perhaps someone within Dublin Bus might be able to answer this question, earlier this week a passenger posted on Twitter questioning why the 8.20 and 8.35 40D did not operate. Dublin Bus Twitter replied that the 8.20 did not operate for mechanical reasons, and the 8.35 departure was moved forward to 8.30.

Can anyone explain the logic behind this? Surely by 8.30, the passengers realise their bus is late and can make a choice to either wait for the 8.35, return home and come back at 8.35, or find an alternative mode of transport.

By moving the 8.35 bus forward, you're just disrupting another group of passengers who will also miss their bus. So, instead of having one bus not run on time, you have two buses not departing as per the timetable, with a bus running in the middle that nobody is expecting. It would appear this passenger missed both the 8.20 and 8.35 bus.

I ask because I've noticed this mentioned quite a bit on Twitter and it was also posted here by another poster who was having trouble with the 56/56A not running. They were told by the depot their bus departed early because the previous bus didn't operate. Is this the policy by Dublin Bus when a bus does not operate? Does this happen on other bus networks?

LXFlyer

Well there is some logic to it.

If you take the example of the 40D that you quote above:

There are scheduled 40D departures from Tyrellstown at 0805, 0820, 0835 and 0850.

If the 0820 is cancelled as per above due to the bus breaking down that means there would be a 30 minute gap in service between 0805 and 0835 and then a 15 minute gap till the next bus along the entire route. Based on an expected frequency of 15 minutes that would be too great. In order to try and reduce the impact that losing one bus had on loads and the schedule, the controller moved the 0835 forward to 0830 meaning you have a 25 minute and a 20 minute gap.

Most people waiting would not return home and come back - they would stay waiting at a stop. How would anyone know that the bus was not operating? It could be running late. Therefore the view is taken that it is better to try to narrow the gap and spread the loading.

It's not ideal, and it particularly grates for anyone showing up after 0830, but the rationale is to provide a form of even frequency and spread the loading over the (revised) 0830 and 0850 departures.

It would be fairly common practice among city bus operators to do this.

KD345

Cheers lxflyer. While having an even frequency might seem better on paper, I 'm not sure I agree with disrupting two groups of passengers for the sake of 5 minutes. I'm assuming anybody using RTPI would know the 8.20 bus is not operating as it would not be showing. They would either walk, return home/wait at the stop for the 8.35 service, especially if in Tyrrelstown where you can see no bus at the terminus.

I know if I got to my stop at 8.32 to be on time for the 8.35 bus, I'd be pretty annoyed to see it leave early.

LXFlyer

Well bear in mind that there will be people waiting all along the route and not just at the terminus. Not changing it means that one bus is trying to cope with two bus loads. By doing this the controller is spreading three bus loads over two buses.

CIARAN_BOYLE

lxflyer wrote: »

Well bear in mind that there will be people waiting all along the route and not just at the terminus. Not changing it means that one bus is trying to cope with two bus loads. By doing this the controller is spreading three bus loads over two buses.

I presume that this is the right reason. The 8:20 and 8:35 passengers could overload the and by spreading the bus out there is less chance of an overflow which would leave passengers waiting at a bus stop

AlekSmart

The principle behind this is called "Regulation of Service" and in the circumstances described in this thread it has to be viewed as an attempt to achieve Compromise in service terms.

Unfortunately Compromise,of itself,means there will be some that benefit and some who don't.

It is to be hoped that the majority gain some benefit whilst a minority suffer a loss.

Some route structures are more amenable to this practice than others and it's fair to say there is a degree of reluctance now on Controllers to practice Regulating as it can skew the route operational statistics which the NTA monitor.

Another factor which can(and should) influence the decision,particularly on a busy route,is the increased likleyhood of the next scheduled departure (0835) is now in a 30 minute gap instead of 15 and as a result risks turned into a Late-Running service of itself with the attendant knock-on effects on the service long after the original problem has been addressed.

The principle here,and it is a widely practiced one worldwide,is to address the Gap issue ASAP and attempt to prevent that Knock-On situation from developing.

With far fewer vehicles and drivers now available there is little hope of having a "spare" bus and driver to slot-in as was the case with the now defunct "Euro-Duties".

Sadly,as was pointed out by Fintan O'Toole in an Irish Times article,"Less cannot mean More" and that remains a fact which has been studiously avoided by all concerned in this equation.....