Under the blended plan, Caltrain and high-speed rail are supposed to share tracks and infrastructure. And yet, for completely inexplicable reasons, Caltrain is installing a PTC signal system incompatible with HSR.
The Caltrain PTC system is called CBOSS. It has already cost the agency over $230 million, a price far higher than comparable PTC projects elsewhere. One reason for the huge cost is that Caltrain elected to develop a custom, in-house system — and this is the inevitable result: