FWIW....Some comments from having spent almost 4 decades working in the Operating Department of CSX and its' predecessors......'Signal Suspensions are relativity common on CSX. They are employed to allow operations to continue when updates and/or changes are being made to the physical track structure and/or signal system on a particular section of railroad. Instructions are issued and are very specific as to what rules are in effect and how train and equipment movements are to be made through the limits during the suspension. This is accomplished by the use of Track Warrant Control and EC-1 Forms (CSXs' authority for movement in non-signaled territory among other uses) In this case the signal suspension was implemented due to the need to make changes necessary for installation of PTC. It had been planned to take effect Saturday morning and expire Sunday evening.
While nothing is official yet, reliable information indicates the switch in question (at the north end of what is known as Silica Siding) was an Electric Lock hand operated switch , meaning it is controlled manually, regardless of whether the signal system is operating or not. Sources tell me it was found in tact, lined and locked in the reverse position (lined for movement from the main track to the siding).
The CSX crew had placed the 2 units and 30 some odd multilevels in the siding approximately 35 minutes before the incident and had reported in the "clear" to the dispatcher, giving up their Main Track Authority (EC-1 form). In layman's terms this simply means that they were giving up their authority to be on the main track at this location, their equipment was clear of the main and all switches were properly lined and locked for normal movement.
AMTRAK 91 was proceeding through the limits with proper authority (EC-1) and had no reason to believe their route was not properly lined.
How and why the switch at the north end of the siding was left improperly lined and by whom is what the NTSB investigation will bring out.
I do hope this answers some questions without confusing the matter any further. Unfortunately This is shaping up to be a Human Factor accident caused by a misaligned switch. Again it emphasizes how even the most fundamental rules of operation need to be adhered to as railroading can be very unforgiving when Operating Rules compliance is not followed through.
CJ
If what you are saying when the CSX freight crew reported "clear" to the dispatcher is accurate then the last part says it all "all switches were properly lined and locked for normal movement" ie: mainline operation ?
There are many possible scenarios as to how the switch was lined for the siding….. here are just a few of the many possibilities;
The crew may have reported "clear" and simply overlooked the fact that they failed to reline the switch for the main. (entirely probable, as this has happened too many times in recent railroad history)….Hence the many operating rule changes and requirements related to hand operated main track switches in both signaled and "dark" territory and FRA Emergency Order 24 issued in 2005 to address such situations.
The Control Station (dispatcher) may have mistakenly given verbal permission to an authorized employee/contractor to operate the switch with out following proper procedure (possible, yet unlikely), as there would be direct and willful operating rule violations involved as the dispatcher would have to override the Computer Assisted Dispatch system which would detect the EC-1 issued to AMTRAK 91 and alert the dispatcher to the conflict of track authorities.
Another employee/contractor (possibly a signal maintainer) may have operated the switch for many different reasons. Keep in mind the purpose of the "signal suspension" was for the track segment to be prepared for PTC and position of switch detection is a major aspect of Positive Train Control.
Unauthorized use..i.e. vandalism/sabotage (possible, not probable).
Remember, having rules in place doesn't guarantee compliance. In the end it is the people performing the tasks, and their strict adherence to the rules, that make the operation work. The simplest of shortcuts and circumventing of the operating rules, or parts thereof, often have had catastrophic consequences.