I can't understand why someone affiliated with the 2926 group says that the air brake equipment cannot be used with PTC.
This locomotive was built with 8-ET air brake schedule, and was formerly equipped with Automatic Train Stop. 3460 Class Santa Fe steam engines, also built with 8-ET air brake schedule, were equipped with both Automatic Train Stop and Automatic Train Control (cab signals). I might add that Southern Pacific 4449 also was built with 8-ET and HSC air brake schedule, and that group has not been complaining about incompatibility with PTC.
Obviously Number 8 air brake equipment can initiate a penalty application when commanded by a train stop device. So, what's the problem?