Horseshoe Curve Pusher Start - Part 2

August 4, 1994 - Two SD40-2 helpers notch out their throttles and scream to the heavens as they get this train moving again after it stopped while wrapped most of the way around Horseshoe Curve and out of sight up the grade. There was blasting work being done at the summit for the Allegheny Tunnel clearance project, and presumably this train was stopped while a charge was set off. Turn your speakers WAY up for this one!

Category:

Autos & Vehicles

Tags:

• Conrail
• Horseshoe
• Curve
• helper
• pusher
• start
• freight
• train
• railroad
• loud
• SD40-2
• Altoona
• Pennsylvania

[KThom885]

He's throttled out to help the head end pump up the air brakes. The air compressors are run off the engine shaft and by throttling up, he's building air faster. When the head end starts to pull, he throttles back, engages the traction motors and throttles back up to get the train moving.

[FastFlyingVirginian]

@KThom885 Makes sense, thanks!

[40ouncekneegrow]

He probably let off to start over on his am-meter when they got some forward movement going under load

[FastFlyingVirginian]

@40ouncekneegrow I see. I've heard the same sort of momentary throttling back on many occasions; I've always wondered why they didn't just hold whatever notch they were in and throttle out from there.

[40ouncekneegrow]

The helpers were throttled a notch or two before moving to hold the train while the headend charged its lines. They can do this without redlining the Tms and when they get a release they notch those badboys out amazing video btw

[FastFlyingVirginian]

@40ouncekneegrow I figured that's what was going on, but I can only guess at why it sounds as if he throttles back before really opening it up. Any idea why they do that?

[bnsf7747]

I miss CONRAIL...

[ChanFram]

this must have been awesome to witness!

[critter221]

@FastFlyingVirginian

Since this BS youtube only allows so many charactors, and will not allow links... I cant explain in detail the exact coarse of events that take place in such a situation.

Jim

[critter221]

@FastFlyingVirginian

There is alittle more to it, but KThom885 has it right for the most part.

Jim

[40ouncekneegrow]

Its all in the amps going to the motors

[FastFlyingVirginian]

@tiddlywink100 I think the general practice is that they shove at full throttle until the entire length of the train is over the summit, in order to keep the slack bunched in. Ultimately, when and how they throttle comes down to skill, familiarity with the line, and communication with the head-end crew.