ECP is to my mind a fairly recent technology, as in 10 years, in this country anyway, and this is just a missed detail. Engineering history is full of right place right time one in a million failures. This was just another. Any braking system that can release brakes uncommanded is begging for it.
The idea behind the reversion to pneumatic - with the overlay systems such as BHP & Rio Tinto use is to enable the use of the pneumatic mode without waiting for the batteries to run flat. Hence the 2 minute reversion with no BP pressure. 60 minutes is enough time to do what you need to do - but you need to know what you need to do, and that involves training and systems understanding, both things that are sadly lacking in in the Rail industry as compared to others. If BHP's procedures required the driver to dump the air before walking, it shows that someone there had an understanding of the ramifications of not
doing so - but there was no redundancy in this. IMHO, not smart.
These air brakes are NOT Westinghouse. They only have a failsafe mechanism that will apply the brakes in an emergency. If the Brake Pipe hose has a sudden reduction in pressure, it dumps, and applies.
These air brakes are built for and ARE EP/ECP.
That is, they are a totally new type of air brake. Westinghouse brakes depend on reduction of air to apply brakes, where as these command via an electric/electronic system using air pressure
BHP and Rio Tinto utilize ECP overlay manifolds on their wagons - that is to say without trainline power and a HEU on the network commanding the ECP to cut-in, they run in standard pneumatic mode, responding to BP pressure changes. Incidentally, this is another
failure mode of ECP. If an individual wagon loses comm, or is not detected on the network initially, it will run in pneumatic with the train in ECP. The small changes in BP pressure as ECP is applied can cause stuck brakes on that out-of-comm car.
Firstly, I refer back to my earlier post relating to Management of the incident by BHP. It's just beautiful! Instead of handing the ATSB a pneumatic hose they handed them an Electrical cable. Here is the fault and we found it amongst all the wreckage, or was the disconnect near the end the train?
Your conspiracy theories are getting a bit old. The datalogger will record ECP faults, including the dreaded "multiple critical loss" alarm, trainline voltage and ECP comm state. One of the first things the driver would likely have reported (based on my
experiences of ECP faults over 7 years driving with it) is that I've just had an