He cracks the MBTA bus-schedule code
By adamg - 8/28/09 - 12:09 pm
Laurance Grosbaum tweets:
"Every 12 minutes or less" for the 73 bus shouldn't mean no buses for 34 minutes and then 3 all at once. Apparently it's an average
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Comments
They do it All the time on the Green Line too
By jinzilla20 (not verified) - 8/28/09 - 1:01 pm
It's not uncommon to wait 20+ minutes for a train on a specific branch of the Green Line as well, then see 2-3 come at once. In fact, if an unusually large crowd is waiting for the D line on the platform when I get there (or the train that comes by is already packed like sardines), I often don't board and gamble that there will be another train in a minute or two. Sadly, I'm usually right... and the second train is ALSO packed like sardines.
I think the MBTA does this because they like to "Run Express" on certain routes and skip stops, or just like making people ride trains that are packed like sardines. They also do it so they can reroute one of the trains at Park Street for a "schedule adjustment".
The "bunching" problem on the Green Line is largely
By roadman - 8/28/09 - 2:06 pm
due to the fact that the dispatcher generally cannot re-route trains to other lines to balance capacity with demand (this is apparently due to some archane union work rules). They can, and often do, redirect cars back to their home terminal enroute - like when a GC car terminates at Park Street - which is another issue I won't get into here.
To illustrate, say there are two Riverside trains arriving at GC in close proximity to each other, but a BC train hasn't left GC in a while. In this case, the dispatcher generally does not have the option of re-routing one of the Riverside trains to BC to serve those passengers. Rather, because both trains originated from Riverside, they must return back to Riverside.
There are ocassional exceptions to this policy, but they are normally few and far between.
Because there is no storage space at GC (what goes into the loop must immediately proceed out), this is the principal reason they implement "headway adjustments" at Park westbound.
As I've noted in other posts, the quickest way management could attain much more consistent service on the Green Line would be to dump the "out and back" routing policy. Instead, run all eastbound (inbound) service all the way to Lechmere, and dispatch the trains back westbound (outbound) not based on where they originated, but on where the next train out of Lechmere is scheduled to go to at that time of day.
This would self correct the problems that the "bunching" of eastbound trains presently creates for westbound service, would all but eliminate the need for "headway adjustments" enroute, will provide passengers with a 2 minute headway between trains from Lechmere to Copley during rush hour, and will eliminate the need for passengers boarding east of GC that are going to Riverside or BC to change trains at GC or Park.
So it violates some work rule?!? Well, what's the union going to do to oppose it? Strike because they're being told where to run their streetcars. I doubt they would get much public sympathy for that one.
Disclaimer - I do now not work, nor have I ever worked, for the MBTA, MBCR, or any of their consultants or contractors
MBTA Work Rules
By Brian Kane (not verified) - 8/28/09 - 2:29 pm
Most MBTA work rules are the result of binding arbitration and are imposed on the Authority by supposedly neutral arbitrators. It is not like the MBTA agrees to these sort of work rules. Once a rule is in effect the T has no ability to unilaterally change it, by law. Your premise that the Authority should change the rule because public sentiment would be on its side (while probably true) is moot because state and federal law precludes that possibility.
To enact such a change the legislature must adopt stronger management rights legislation which could allow the MBTA to run the system in the best interest of the riders. The fault rests on Beacon Hill, not 10 Park Plaza.
Bingo
By Kaz - 8/28/09 - 2:29 pm
The *real* kicker in my mind is watching 2 doubles run down the B Line back-to-back at *WASHINGTON* already. That means that they were sent from the BC terminal come hell or high water whenever they were "supposed" to as opposed to sending the first one a little early to cover the fact that the previous one left so long ago and the platforms were pretty full when the trains were coming into BC. The first train gets bogged down by Washington and the second train has already caught up to it and starts playing tag until *someone* in the system gets the bright idea to finally express the first train (when it could have just left a bit earlier to build the gap behind it).
It seems like there's *always* headway adjustments by delaying trains to create some space down line...but NEVER headway adjustments by sending a train sooner than scheduled to adjust for heavy volumes of passengers down line.
It's like clockwork too, but it seems the schedule never gets adjusted either. The morning "rush hours" always end up leaving 3-4 trains running back-to-back-to-back-to-back heading OUT to BC around 9-9:30 AM (after the "rush") but you can wait 20-40 minutes on the Washington St platform after that before you see 1 coming inbound...and it's almost ALWAYS followed closely by a second train again already.
Same for buses. Two 57s
By J - 8/28/09 - 4:02 pm
Same for buses.
Two 57s leave Kenmore together MOST of the time. And no, instead of boarding together and running one express to Packards, theyre both local (skip stops). So the first will stop at Blandford, the second will skip that and stop at CAS, and thell meet up again at the light at the BU bridge.
I understand bunching at the end of the line, its inevitable. But bunching from the first stop? What?
66 bunching
By Molly - 8/28/09 - 4:21 pm
I often see 3 66s in a row at Roxbury Crossing headed for Dudley. I realize that's the end of the route, but I never understand why there can be 2 66s in a row at Roxbury Crossing headed for Harvard. And they'll both stop. What?
Buses can start bunching
By anon (not verified) - 8/28/09 - 8:33 pm
Buses can start bunching fronm the start of a route if one of the buses is running so late from its previous trip, that it eats up all of the recovery time built into the schedule, and then departs for its next trip late (with the follower bus, running right behind it, but on time).
The point is, the first bus
By J - 8/31/09 - 2:22 am
The point is, the first bus should be sent express as to fix the problem