ALCo PA/EMD E7B

Not NYC, but it has been done:

F units, too:

Rusty

I believe from the start c.1940 EMD and ALCO used the same (or at least compatible)systems to m.u. engines. Since an E-unit and PA unit are both geared for high-speed passenger service, they could run together with no problems. It wasn't uncommon to see  freights with a say a GP-7 and RS-11 together, or GM F-units and ALCO FA-FB units running together.

I have seen NYC trains with PAs, either with all PAs or in the trailing position (there's a few scenes with them on video).

Ok, so that was the "early days"; did this change?

Thanks, again.

- Mario

Thank you.

I've seen many photos and videos of PAs and E8s together in passenger service on  the Erie Lackawanna. My understanding is that engineers liked the quick response of the lead PA needed from station stops and the steady and smooth power of the E8s.  It was a popular combo.

Conductor Earl     

"Standardization leads to some pretty non-standard applications."  I heard this in an ANSI standards committee meeting several years ago, and I guess it applies to trains, too.  Never thought of that . . . .  

Interesting and nice pictures.  Thank you for the info.  I may have to run something like that some time . . . 

Unlike with the purchase of 6000HP A-B-A E7 "sets" the PRR purchased A-A sets of EMD E8's.  For exceptionally heavy trains that required 6000HP they would pair the E8's with an EMD E7 B unit from a downsized "set", or an ALco PB-1.  For several years PB-1 units retained their original passenger gearing while their former PA-1 mates were re-geared for freight service. Photos even show ALco PA-1's in helper service on the Elmira branch! 

Ed Rappe

Real common to mix EMD and Alco locomotives, both freight and passenger, on the Missouri Pacific.

Thier Baldwin diesels were not compatible as they had air operated equipment.  Dan

PA-E7B- PA

http://www.westernrailimages.c...099378&k=bR7SJxm

Many need to enter picture 127!

There is also photographic evidence of EP22s (E8) in freight service on the Penn...and not just mixed with each other, or on Truc Trains.

Another impediment to m-uing of EMD and Alco diesels of the first generation was sanding and dynamic braking incompatibility.

Most railroads did not use dynamic braking on their E-units and PA's, so, if the sand control was compatible, the two manufacturers' locomotives would m-u more easily.  

However, with dynamic brake, EMD used field loop control, involving a 2-wire  (or was it 3? Time flies.) cable with a rectangular connection to the locomotive, while the GE system used by Alco used potential line control, using pins of the 27-pin jumper.  Therefore, the DRGW photo depicts a situation where the dynamic brake would work on the Alco-GE PA, but not on the trailing F-units.  Ditto for the SP PA if it was dynamic brake equipped and it appears to be a PA 2 or PA 3 which would have been.

DRGW, UPRR, SP and Santa Fe were the only roads that used dynamic brake on their PA's.  SP and UPRR used dynamic brake on their E8 and E9 units.  You may notice that Santa Fe and UP basically did not m-u Alco and EMD passenger units.  SP had a group of former T&NO and two former Cotton Belt PA's that were not dynamic brake equipped, and these are usually the ones which were used with the E7's.  MoPac and Wabash routinely m-ued E's and PA's, but again there was no dynamic brake involved.  Santa Fe and UPRR m-ued Erie-Builts and PA's, but both had GE electrical equipment and were compatible.  Santa Fe Erie-Builts and PA's had electrical/pneumatic sand control, while the EMD's had straight pneumatic.

Every essential function such as sand must be able to be controlled on all units in the consist, from the controlling (usually leading) unit.

As an aside, referring to the photo of a NYC Alco/EMD consist seen in a photo, the only such photo I ever saw was of a  EMD E-unit and a re-engined (with an EMD engine) Alco.

BINGO!  I'm not crazy!

That E7B will make sure that Cleveland W/B M&E makes it at least as far as Toledo !

Any information on when, and where that photo was taken?  Sure is a nice looking secondary train with lots of baggage cars on the headend.

Short answer..... YES!

West bound M&E #35 at Collinwood, OH in 1962.

Here's the opposite, too!

BTW... I have found documentation that PB #4302 was re-engined by EMD in 1955...

Thanks,

Mario

shhh! you're just a voice in my head!