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by coumbaya
587 days ago
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Another tidbit: on high speed trains (maybe on regular trains too idk) the 'door flange' which is actually a hollow pneumatic tube (it can detect spike in pressure that's how the train know it's trying to close the door on somebody's hand) get's pressurized higher before entering the tunnel, to mitigate the "slam" effect due to the difference in pressure. |
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