8-car Bomb Consist

[District D RTC]

I can't seem to locate the post to add this reply to an existing thread so here we go:

Today while out to catch AMTK#49(17) with the NJT Comet-1Bs on the rear (again) I observed an 8 car train. I know in the past this has been a rare occasion. I'm told that this is currently being done with TWO trainsets to provide additional capacity on the NHV side where those two sets are runing during the rush on one of the 'combined' trains.

Anyway, here's the video showing the 8-car train:
http://www.youtube.com/watch?v=xCgNXB8rejQ


Truth be told I didn't even notice it myself when I was filming the video --- rather it was brought to my attention by Mr. G of Beacon.

--JSW

[truck6018]

One day earlier this week I was on a Hudson Line train from Poughkeepise to GCT that was an 8 car train.

[checkthedoorlight]

Typically when I see an 8 car bomb set, the first and second cars are both cab-cars, the second likely one that crapped out.

I heard that they were breaking up the sets and making some 5 car sets as leftovers. They're turning into NJT!

[Clean Cab]

An 8 car Bomb train really puts a strain on the P32AC-DM's (AKA 'Gennies"). 8 cars draws almost 1000 horsepower from the 3200 HP engine, leaving about 1/3 for traction power. This is the drawback to locomotives that use a single motive force for both traction and HEP.

[checkthedoorlight]

Yet Amtrak's single P32 can handle the 9 car LSL on its own?

[DutchRailnut]

Yes but they do not stop and go every 3 miles and do not open up a entire side of doors which will cause big draw due to heat and AC, specially on centerdoors.
Kepping a train going does not require much HP, but HEP and stop and go does.
a 8 car Bombardier draws about 100 hp per car for HEP, leaving 2400 hp for traction on a locomotive geared for 110 mph.
compare that to single FL-9 at 1850 hp being geared for 73 mph (gearing not speed) and you see difference narrow to point of a Genny and 8 cars equals one FL-9 and 8 cars.
was it do able for Amtrak, sure, but not do able for commuter service.

[Clean Cab]

I remember many years ago seeing Amtrak 49 on the Hudson Line with 1 FL-9 pulling 10 cars.

[Tommy Meehan]

An 8 car Bomb train really puts a strain on the P32AC-DM's.

Bring back the P motors and the power change at Harmon. (It only took four minutes.)

[DutchRailnut]

not with todays blue light protection and HEP and 27point jumpers.
more like 30 to 35 minutes.

[metrony]

Just this past week someone caught an 8 car bomb at Breakneck Ridge. What was the reason for another shoreliner?

http://www.youtube.com/watch?v=v67VPcF1e9c

[DutchRailnut]

reason is posted in first post

[UpperHarlemLine4ever]

Yes, those old P motors were great units. After a pair of RS-3's would bring a 12 to 15 car train down from either Chatham or Albany, it would be turned over to a single P motor at either NWP or Harmon for the trip to GCT. I can well remember being at Woodlawn, Fordham or University Heights and seeing a train fly through being hauled by a P motorand it was much larger than 7 cars. Since they don't want to do an engine change, with all the technological know how of today why can't they build a dual mode locomotive that can handle 10 or 12 cars?

[Ridgefielder]

Yes, those old P motors were great units. After a pair of RS-3's would bring a 12 to 15 car train down from either Chatham or Albany, it would be turned over to a single P motor at either NWP or Harmon for the trip to GCT. I can well remember being at Woodlawn, Fordham or University Heights and seeing a train fly through being hauled by a P motorand it was much larger than 7 cars. Since they don't want to do an engine change, with all the technological know how of today why can't they build a dual mode locomotive that can handle 10 or 12 cars?

My off-the-cuff guess would be weight constraints on the Park Ave. viaduct. That, and there doesn't really seem to be a need for one under normal operating conditions.

[metrony]

Plus all the platforms north of Harmon are 6 cars. Once in a while the Hudson Line trains can get really crowded and maybe an 8th car would help, but for the most part 7 cars is good enough.

[Tommy Meehan]

My off-the-cuff guess would be weight constraints on the Park Ave. viaduct.

The weight restrictions of old were based on axle loadings. Supposedly that was why the FL9s were designed with a three-axle rear truck, spread the weight. I think Metro-North has possibly increased the axle ratings on the Park Ave. viaduct.

A bridge or viaduct has to have a lot of capacity. Each section has to be able to handle a heavy train on each track simultaneously plus a margin of safety.

They raised the speed limit on the Park Avenue viaduct from what it once was, that's for sure.