Discussion related to commuter rail and rapid transit operations in the Chicago area including the South Shore Line, Metra Rail, and Chicago Transit Authority.

Moderators: JamesT4, metraRI

  by Metra210
 
While filming Metra trains, I've noticed that some trains are led by two locomotives instead of one. This usually happens during the rush periods and on weekends. I've seen it on just about every Metra line, and with every locomotive model including the MP36s. Some trips commonly have two locomotives leading a train (e.g. MD-N Line Train #2143 which departs CUS at 5:52 on weekdays).

I once heard that the reason behind doubleheading was to reduce fuel consumption, since both locomotives are not in Notch 8 when pushing or pulling a train. Another reason I heard is because one locomotive is experiencing a mechanical problem of some sort and the other, usually the one in front of it, serves as the leader.

An image of a doubleheaded Metra train is provided below. I filmed Southwest Service Line Train #831 on Tuesday April 16th, 2013 at the Lumber Street crossing in Chicago's South Loop. This train is going outbound, and the leader is F40PHM-2 #200. Behind it, is F40PH-3 #113

pic.twitter.com/mMV1xOY0hb

I've always wondered why two locomotives are sometimes used to power a Metra train instead of just one, and I'm not exactly sure if what I've heard is 100% accurate. Can someone explain why this is done? Thanks very much.
  by doepack
 
Metra210 wrote:I once heard that the reason behind doubleheading was to reduce fuel consumption, since both locomotives are not in Notch 8 when pushing or pulling a train.
That's possible, never heard that before...
Metra210 wrote: Another reason I heard is because one locomotive is experiencing a mechanical problem of some sort and the other, usually the one in front of it, serves as the leader.
Another fairly common reason. Especially when a protect unit is fired up from a terminal for a "rescue" mission. But usually, they'll send an extra locomotive to an outlying terminal on a revenue run to serve as a protect unit for the next morning's rush in case something breaks overnight, although there are exceptions. One of which involves UP/NW run 625, a train that always runs with 2 units. Why? Because on its return trip to OTC as 658, the 9 or 10 car train is split into two shorter trains (normally UP/NW 661 and UP/W 67), and having an extra unit facilitates this move more efficiently...
  by metraRI
 
Due to each district having separate mechanical departments, there may not be a single answer to why trains are double headed. Unlike MD/UP, RI/SWS no longer have a regular/daily double header... I have heard this was done to save fuel. Instead a protector unit is now placed at 179th Street on SWS and at LaSalle Street on RI. The protector at 179th is usually swapped out about once a week (unless needed), while the protector at LaSalle is alternated on a regular basis. On RI, if a problem with a loco occurs, the "trouble" unit is paired with another and usually placed on train #413 (what used to be the regular double header).
  by Tadman
 
Over at Amtrak there are specific guidelines for when a double-headed consist can have both locomotives on line. Supposedly they try to leave the leader off line in order to save fuel. This was told to us at the Amtrak forum by a few engineers. Given that info, I can't imagine Metra would do the exact opposite as a fuel saving measure.

It's my understanding with Metra that the doublehead moves are simply the way to move the protect unit downtown or to the burbs at the end of the respective rush hours.
  by lstone19
 
I've only been commuting on the MD-W but as far as I know, we no longer have a protect unit at Elgin overnight. My understanding is 2216/2237 used to be double-headed but when it was increased from nine cars to ten, lost the second unit suggesting that it was up against a length limit.
  by MetraBNSF
 
In the case of BNSF they don't keep protect units at Hill Yard in Aurora or at CUS itself. Instead they might keep a unit at 14th St. Most of the time one set is run with two locomotives. In the weekday afternoons its either trains 1269 or 1277 that run with two locomotives.