Re: Beresfield Accident Findings

[matthew@mail.usyd.edu.au (Matthew Geier)]

markbau1@aol.com (MarkBau1) writes:

>I just checked with a BNSF Engineer who is also somewhat of a BN historian, he
>has never heard of any system that involves "dispatcher intervention"

>One of the earliest problems was that PTS could not pintpoint trains accurately
>enough so that at a crossing loop it couldn't tell which track the train is on.
>The US military/Rockwell has the ability to pinpoint locations much more
>accurately but it will not release the technology for non military use.

 I belive these trials are also trying 'differential GPS' were you use a
fixed GPS reciever to work out the error factor in the GPS signals, thus
get an accurate position (to the system limit of GPS), and strategic
posititioning of transponders around loops to provide the additional
accuracy. Transponders mean equipment in the field, something they are
trying very hard to avoid.
 There was a write up about the PTS trials in RGI some months back.