'Reckless' Amtrak engineer, 32, who was driving doomed train at 106mph in a 50mph zone claims he has no memory of crash that killed seven - with a DOZEN passengers still missing
By Wills Robinson and Lydia Warren for DailyMail.com
13 May 2015 | Updated 14 May 2015
http://dailym.ai/1HiPCbI

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THE DEVICE THAT WOULD'VE PREVENTED THE TRAGEDY: WHAT IS POSITIVE TRAIN CONTROL?

The commuter rail route where an Amtrak train left the track on Tuesday was not using a potentially life-saving braking technology.

Known as positive train control (PTC), the technology automatically slows or even halts trains that are moving too fast or heading into a danger zone.

It can override a train conductor who is exceeding speed, and under current law, the rail industry must adopt the technology by year end.

PTC works by using a global positioning satellite to pinpoint trains. The idea is that it can do this with enough accuracy to allow them to run closer together.

It sends real-time visual and audible information to train crew members about locations where the train needs to be slowed or stopped.

Among other things, it takes into account approaching signals, speed limits, curves in the track, construction work and the position of approaching switches.