Eastern Railroad Discussion > NS 1800/1801 SD70ACC and ET44AC Adhesion Testing in Roanoke

NS SD70ACC's 1800 and 1801 were recently adhesion tested on Starkey Hill in southwest Roanoke, VA. These units are rebult SD70's that have new cabs, traction motors, control systems, etc. The units were expected to perform similar to an SD70ACU (SD90MAC) rebuild and after some software tweaks and other adjustments, did just that. Both wet and dry rail tests were performed with tonnages ranging from 8500 to almost 10,000 tons. Overall the units performed very well and proved they are some of the strongest pullers in the fleet.

Photo1: NS 1800 and 1801 sandwhich NS Research Car #32 in Roanoke South Yard

Photo 2: NS 995 test trains grinds up Starkey at Milepost R-10.5

Photo 3: Last day of testing, NS 1800 crests the grade at MP R-11

Enjoy!

Hank
 



Edited 4 time(s). Last edit at 10/14/18 21:16 by hdralleiii.

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Photo 4: NS 1800 leading the 995 test train at MP R-9.7

More photos and videos to follow....

Enjoy!

Hank



Edited 3 time(s). Last edit at 10/14/18 05:00 by hdralleiii.

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Great stuff, thanks for sharing!  Are they now free roamers or will they stick around Roanoke and the Punkin Vine to break in?

Cooper

They will be headed back north to have some additional mods completed prior to be released for service.

Posted from iPhone

Bummer.  Thanks!  

Very nice..!!

Looking forward to the videos.
John

Thanks for posting.  I want to see them on the road.  Gerry

How do you do an ahesion test?   Gun it from a dead stop???

Love the pictures and the paint scheme

Posted from Android

Tominde Wrote:
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> How do you do an ahesion test?   Gun it from a
> dead stop???

The way NS performs testing is to setup a baseline tonnage consist based on the "expected" ability of a particular unit. A set of equivalent helpers gives the train a little nudge at the bottom of the grade and helps get the train to 10mph. Once that is done, the helpers back out of the throttle to idle and let the head end pull. The helpers need to be equivalent so they can safely bring the entire train back down the hill. The purpose of the test is to see how long the units can maintain speed, how much wheel slip is present and how well they recover after crossing flange lubricators, negotiate tight curves, etc. The idea is to find the highest tonnage a unit can pull without a lot of fluctuation of speed, which determines their continuous tractive effort. These tests are conducted on both wet and dry rail. Wet rail is simulated using water jets in front of the leading truck to saturate the rail head thus creating a more slippery rail surface. The latest units from both GE and EMD have new "Rail Cleaner" systems that actually deploy varying volumes of air onto the rail, just before the sander, to clean off debris and actually dry the rail head to increase traction. Attached photo shows a wet rail test up close.

Over the last several weeks, SD70ACU (SD90MAC rebuilds), SD70ACC (SD70 rebuilds), and GE ET44AC (new units) models have been tested. Consists ranged from 8500 to nearly 10,000 tons. All performed extremely well. 

Hank
 



Edited 1 time(s). Last edit at 10/14/18 21:11 by hdralleiii.

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Photo 1: GE Tier 4 ET44AC's 3649 and 3630 lead a 995 test train with Research Car 32 up Starkey Hill in Roanoke
Photo 2: Tier 4's sandwhich NS Research Car 32 in Roanoke South Yard. The water tanks can be seen behind the cab.
Photo 3: NS 3649 is about to head south from Roanoke after getting the water tanks filled (opposite side of loco) for another wet rail test

Hank

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Here is some video of the units climbing Starkey at MP R9.7

https://youtu.be/cODUvoNXu-g

Hank

Amazing paint scheme!

Thanks for the video.
John

I’m really glad the SD70ACC so far is acquiting itself well. Need the 710 roar to help balance out the constant GEEVO chug!

Posted from iPhone

Oh, that yellow is going to fade bad...

Victor A. Baird
http://www.erstwhilepublications.com

Great info, pics and the video. Thank you.
 

By far, NS is proving to be the most interesting RR out there (once again) with regards to motive power.  Just as they did in the days of steam, so they do in this day of diesel---build, design, experiment, and find the best power they can.  You gotta love their independence and smarts to do all this work.  And the new paint schemes are great, too--very eye catcing.

Norfolk Southern Railway:  Railroad & "Image" of the Year.

It apparently took Norfolk Southern almost three decades to realize most people think Paul Simon was right...
("Everything looks worse in black and white", that widely held wisdom from the song "Kodachrome")