M3 # of Cars

I read that the number of M3 cars for the MFL was 270. The number of M4 cars is 220. Why the difference in number? Service decrease?

KLCS wrote:I read that the number of M3 cars for the MFL was 270. The number of M4 cars is 220. Why the difference in number? Service decrease?

Basically that's it. The MFSE runs a 4 minute frequency now compared to 25 years ago where the El ran a 2.5 minute frequency. It creeped upward as ridership fell due to the usual reasons; decline in the City's population, decline of jobs in Center City, other forces in and out of SEPTA's control.

Before the M3's the car fleet was a whopping 315 cars for this line, and that was despite the abandonment of the Ferries Branch in 1939.

duh....wasn't the whole point of installing ATC to increase headways?

No wonder the El is always standing room only, fewer cars, greater headway.....And now they need to spend millions for a computer system to keep them 4 minutes apart where the old operators did 2.5mins on block signals.

Wonder what the headway was on the old semaphore setup....SEPTA wastes again.

AND....if the city continues to grow, there is little or no room for expanding service as we're maxed out with the number of cars we have, have shorter platforms on newer stations so trains can't accomodate 8 cars....doesen't anyone do growth projections, or do they assume ridership will forever decrease? Maybe the guys at 1234 haven't noticed all the new people moving into Center City.

Seriously, what is wrong with block signals? Or centralized traffic control (CTC)?

WHY do we need a computer to tell trains to be so far apart when humans have been doing it for decades before this?

WHAT HAPPENED TO SIMPLE??

WHY do we need a computer to tell trains to be so far apart when humans have been doing it for decades before this?

A computer dosen't tell the M4's how far to be appart. The line uses inductive loop cab signaling for both track and signal speeds which enforce a speed limit which the operator then must follow. On the MFL most of the signaling was devoted to keeping trains from running too fast around curves or down grades rather than keeping trains from running into eachother. All the signal upgrades did was eliminate the wayside signals, timers and the trip stops which all had significant maintainence tags. Moreover, the signaling upgrade was a free gift by AdTranz due to delays in the M-4 project.

The result has been a mixed bag. In some places the trains run faster than with the old timers...other places they have been slowed down slightly.

Or centralized traffic control (CTC)?

Before the upgrade the line didn't have CTC and any wrong-railing would reduce capacity drastically. While I'll miss the old ABS system as much as anybody, don't confuse what SEPTA installed here with ATO or CBTC.

Why did SEPTA call it a ATC/ATO system then when they did the rolling El shutdowns a few years back?

jfrey40535 wrote: Maybe the guys at 1234 haven't noticed all the new people moving into Center City.

Actually, most of the people that's moving into Center City tend to work there, or tend to work in the suburbs, so the MFSE isn't really needed. The CC'ers that work in CC tend to walk, while the ones who work in the 'burbs tend to drive, or take Regional Rail.

The only time I might see a CC reisdent using the El is if they work in University City, or in the Temple U area.

jfrey40535 wrote:Why did SEPTA call it a ATC/ATO system then when they did the rolling El shutdowns a few years back?

Cab signals are a form of ATC = Automatic Train Control. If the operator does not reduce his speed when the cab signal drops the permitted speed, the train brakes will apply automatically at a full service rate, from which the operator will have to recover from.

The MFL signal system is identical to the ATC/cab signals installed on the Route 100 Norristown High Speed Line. And while it ended up being a free gift to SEPTA, it was always in the plans to be installed as part of the M4 project. They only got it free as a concession to the delays with the car deliveries.

A similar ATC/cab signal project is in the works for the Broad Street Line as well, but I've got no dates for when it is to be completed. Some of the preliminary work is in progress now though.

If the wayside signalling system was due for replacement, it would make sense if a cab signalling/ATC system was installed, as it costs less than installing an ABS/trip stop system.

To add to my previous post.....cab signal display units and related equipment will have to be installed on the B4 fleet as well, as part of this project.

I'm having nightmare visions of our views out the front being blocked by a silver ATC box being placed in the left side of the operators cab (aka Boston Orange Line and Red Line cars).

As long as the railfan seat's view doesn't get blocked.