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Tehachapi Runaway! (brakes Not Working)

Discussion in 'General Discussion' started by ajp31, Jun 29, 2021.

  1. ajp31

    ajp31 New Member

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    Playing through the second career scenario that came with the Tehachapi route (Hot Box Part 2), with the BNSF locos. On the downgrade over the last 5-6 miles into Mojave, my train consistently becomes a runaway. Dynamics, train brakes, loco brakes all maxed out. Brake multiplier set to "easy," but that doesn't seem to matter. What am I doing wrong?
     
  2. roysto25

    roysto25 Member

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    Could be you were close to track speed limit - if so, you would have to brake really early because, if you wait until you are on the downgrade, speed can increase faster than the brakes can kick in and the kinetic energy makes it very difficult to recover. On most US locomotives, dynamic braking is most effective between 10 and 23 mph and decreases in effectiveness quickly past the upper limit. I am assuming you have DP set correctly. In the real world, engineers may need to apply hand brakes on some of the wagons, if train load is close to retard limits.
     
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  3. Michael Newbury

    Michael Newbury Well-Known Member

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    I found the same issue and reported it as none of the brakes work. I had the dynamics, train and loco brakes fully applied and it made no difference. I ended up with a runaway train coming into Mojave.
     
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  4. Michael Newbury

    Michael Newbury Well-Known Member

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    When I ran this same scenario I had the same issue with the brakes. I was under the speed limit, and as my train was on the crest of the hill I setup the dynamic brakes. And started to apply more dynamics as more of the train was on the down slope, even tried applying min train brakes and nothing happened other than a runaway train.

    I submitted a report to DTG.
     
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  5. ajp31

    ajp31 New Member

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    Doesn't matter how fast I am going when I start using the brakes. Sometimes when I get to max train brakes (and get a "PCB reset" message), the train will actually stop. When I release, gravity does its thing and no amount of dynamics and friction brakes hold it back. The train brakes only seem to work if they're on 100%, and even then, not consistently. Dynamics would appear to have no tangible effect whatsoever. Past experience with simulations would seem to suggest that the dynamics from four modern locomotives could hold a 50-car train on a 2% downgrade, especially in that 15-25 mph sweet spot, but that certainly isn't what's happening here.

    Yep, this is exactly what I'm seeing. Glad it's not just me. ;-) Thanks for submitting a report; I'll do so as well.
     
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  6. Michael Newbury

    Michael Newbury Well-Known Member

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    It's very frustrating and it takes all the enjoyment out of the run.
     

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