We are closer to 2.7kms these days. Yes we still run pneumatic brakes but we run electric over pneumatic control systems. Not a smancy as electromagnetic retarder systems but we can do cool stuff these days like brake the portion of the train that can is travelling down hill while not effecting the portion of the train that still travelling up the hills, or brake from the rear wagons progressively through to the loco to stabilise the train etc etc