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Dude’s a lineman. I don’t think I’d have either the quick thinking or courage to do what he did. You can see him hesitate for a second before committing. He apparently donated most of the reward he got to the kid for his education.
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Damn. That’s a lot of momentum to arrest even for a 2 second window.
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Replying to @vgr
And the loco pilot applied emergency brakes giving an additional 2 seconds. twitter.com/rajtoday/statu
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Rough calculation for fun. Normal speed 100-105 km/h but slamming the emergency brakes brought it down to 85. Train weighs I’d guess 10,000 tons? If it shed that energy over 5 seconds, I calculate a brake power output of like 213 MW. Did I do that right?
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Less rough calculation. A typical Indian passenger train weighs in at around 1300 tons, so that’s a factor of 10 less, so we’re talking 20 MW brake power. If it was 10 seconds instead of 5, brings it down to 10 MW. Still a lot, but not outrageous.
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Replying to
That seems more reasonable. Though brake power can of course be much higher than engine power, especially for a hundred or so steel on steel friction contacts. Now I want to calculate the force per wheel, but I’ll stop the yak shaving now.
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Replying to
Oh yeah I think 10 MW is totally possible. There's a lot of rail so friction would be spilling that heat over a very large area. The more fun calculation wouldn't be force per wheel but noise in dB and delta-T of track
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Replying to
See other branch. Size of train mostly doesn't matter but increasing size of train increases the length of the train increases total cold steel the train passes over for identical speed profiles from the start of the maneuver to the end.
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