# Schedule padding on commuter rail?



## jebr (Sep 22, 2012)

Is it typical for commuter rail to have padding on the ends of the trip, much like Amtrak does? It would seem, especially since there's a lot of point-to-point (not necessarily endpoint to endpoint) that timing could be an issue, especially since commuter rail is expected to be time-sensitive (as people use it for commutes to work and such.)

Northstar puts a 5-minute padding on a route that is only 49 minutes (or 44 without padding)...that's over 10% schedule padding!


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## acelafan (Sep 22, 2012)

It's probably standard practice in most markets, I know Boston adds a few minutes on the Framingham/Worcester line.

Better to have happy customers arrive a few minutes early than mad & a few minutes late.


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## jis (Sep 22, 2012)

In NJ it is called Shirley time and is usually of the order of 10 mins on a typical run, spread out over the run, but at least half of it in the last segment. Also NJ schedules trains assuming the least capable equipment possible, this in reality in most cases the effective padding is more than what appears in the timetable.


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## Anderson (Sep 23, 2012)

The problem with looking at padding as a percentage of time on a shorter run is that, well, a 5-minute pad is pretty small in absolute terms. It's sort of like spare cars...you end up needing a larger percentage of them as a share of the fleet with a smaller fleet to ensure service because a single car can be 5% of a fleet of 20...hence at least part of why you tend to end up with 20% spares as a rule...but 25% spares among the Heritage fleet.*

*Yes, some of this is also reliability-related, but only having a fleet of 20 cars covering three sets of city pairs is going to force a lot of spares/backups in relative terms when you wouldn't need many more such cars if you ran 3-4 times as many such cars between those cities (only extras for inspections and the like).


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## fairviewroad (Sep 24, 2012)

The problem with schedule padding on a commuter run is that riders can more easily make a comparison to driving. Amtrak can through in an extra

hour or two on the Empire Builder because most people probably aren't choosing a LD train because of its speed or lack thereof. But for someone

riding from the burbs into center city, you might say "I can drive that in 40 minutes but the train is scheduled for 49 minutes" and make their decision

based on that. But if you take out the 5 minute pad, the train looks somewhat more palatable.

Likewise, on a small handful of systems such as SEPTA, most inbound trains "run through" and become an outbound train. If you pad the schedule, you'd end up

with an inbound train blocking the tracks at a downtown station waiting for its outbound departure time. Obviously this isn't an issue on single-route systems like

Northstar or places like Chicago where none of the Metra trains "run through."


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## jebr (Sep 24, 2012)

fairviewroad said:


> The problem with schedule padding on a commuter run is that riders can more easily make a comparison to driving. Amtrak can through in an extra
> 
> hour or two on the Empire Builder because most people probably aren't choosing a LD train because of its speed or lack thereof. But for someone
> 
> ...


Bingo.

The other problem, especially during non-rush hours, is connections. Most online tools assume a certain amount of time to make a transfer (for example, Google Maps allows a few minutes to walk the block from Target Field Station to the bus ramp.) As such, the main express bus to St. Paul leaves three minutes after the train "arrives" according to the schedule. If the train doesn't need the buffer, there's plenty of time to make that connection, but Google Maps won't show you that.


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## jis (Sep 25, 2012)

fairviewroad said:


> Likewise, on a small handful of systems such as SEPTA, most inbound trains "run through" and become an outbound train. If you pad the schedule, you'd end up
> 
> with an inbound train blocking the tracks at a downtown station waiting for its outbound departure time. Obviously this isn't an issue on single-route systems like
> 
> Northstar or places like Chicago where none of the Metra trains "run through."


SEPTA schedules are already so padded that they are on the verge of hitting the problem you describe. For a suburban system they have incredibly long dwell times in the city stations when compared to similar systems elsewhere in the world.


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## AlanB (Sep 25, 2012)

jis said:


> fairviewroad said:
> 
> 
> > Likewise, on a small handful of systems such as SEPTA, most inbound trains "run through" and become an outbound train. If you pad the schedule, you'd end up
> ...


Well to be fair, at least part of the dwell time at Suburban Station is to allow for the crew change that always occurs there.


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## Nathanael (Oct 3, 2012)

jebr said:


> Is it typical for commuter rail to have padding on the ends of the trip, much like Amtrak does?


Yes, everyone puts padding on the ends of trips, but it's usually smaller.



> Northstar puts a 5-minute padding on a route that is only 49 minutes (or 44 without padding)...that's over 10% schedule padding!


That is fairly high padding.


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## Trogdor (Oct 3, 2012)

Five minutes is not very high. One actual delay (waiting for conflicting traffic at a signal, for example) can eat that up quite easily.

The shorter the trip, the higher the percentage will be for recovery time.

On the other hand, Metrolink's weekend schedule has about a half hour of recovery time into Oceanside.


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