NS, CSX, and other US freight RRs' locomotives are being outfitted with I-ETMS PTC while the MBTA is implementing ACSES II based PTC. Pan Am and MBTA agreed formally in 2014 (with then MBTA GM Beverly Scott) that:
- the PAS-owned track between Wachusett and Fitchburg and the MBTA owned track between Fitchburg and CPF-WL Ayer would have both I-ETMS and ACSES II PTC technology installed, permitting NS and other freight RR locomotives that regularly appear on NS trains 22K/23K/28N/287 to run under I-ETMS to CPF-WL at Ayer.
- MBTA would pay for the outfitting of I-ETMS/ACSES II on a select Pan Am locomotives that run on the MBTA (eg, EDPO/POED/SEPO/POSE/locals)
But in 2016 MBTA elected not to pursue I-ETMS wayside and equipment work. And I believe that MBTA is committing to install only ACSES II on 25 Pan Am locomotives (per the MBTA's Q417 PTC progress report filed with the FRA). See photo of relevant article snip-it.
Here's a link to the full September 2017 article decribing Pan Am and MBTA's claims/counterclaims:
http://masslegalresources.com/massachus ... -12-124-17
So I think Pan Am and MBTA remain at legal loggerheads re: PTC implementation, but I hope I'm wrong...