Customer safety is a top priority at SEPTA and a driving force behind the modernization of its Regional Rail infrastructure.  Slated to begin shortly, customers on the Warminster Line will see the reflective yellow safety jackets of SEPTA Engineering, Maintenance & Construction crews hard at work making improvements to the track, signal and highway crossings in order to increase travel reliability over the branch. A major element to the Warminster Line modernization is the installation of an Automatic Train Control system (ATC).  Three principles make up ATC – keeping trains a safe distance apart from each other, enforcing the speed limits of the track, and ensuring the train stops when a signal indicates.     Automatic Train Control will eliminate the need for signals, like the ones in these pictures, along the track area. But how does this all work?  ATC signals are much like traffic lights on a highway, only with a twist.  Green means go, red means stop and yellow says proceed with caution.  The twist, however, is ATC signals get displayed inside where the train is being run from, instead of hanging outside like highway traffic lights do.  That effectively means the operator of the train, the Engineer, always knows what color the signal is and can instantly react as soon as the signal change. Once installed, the Automatic Train Control system will help add capacity to the track by allowing trains to be run closer together.  The addition of the Warminster ATC system is part of an Authority-wide goal to control 87% of the 210 miles of Regional Rail track by Automatic Train Control. An additional interlocking, or track switch, will allow more flexible train movements outside Warminster Station. The modernization will upgrade to a remotely controlled interlocking near Roslyn and Willow Grove, while adding a third outside Warminster station.  The fundamental principle behind an interlocking, or track switch, is to move trains between one track and another.  The remote control portion links to the SEPTA Control Center for computers and dispatchers to control the intended path of trains.  The upgrade to Roslyn interlocking will permit trains to travel up to 45 MPH through the switch, while the additional interlocking at Warminster allows a train up to eight cars long to pass another train near the station.   New pedestrian warning devices will be included at Warminster (left), Crestmont (right) and Willow Grove stations. New warning devices are set to be installed along the rail line.  At Crestmont, Willow Grove and Warminster station, pedestrians will soon receive a visual and audible warning when trains are approaching the station.  These devices identify the direction a train is traveling from and provide adequate warning so the tracks remain clear.  The vehicle grade crossing at the intersection of Easton and Susquehanna Road nearby Roslyn Station will be completely replaced and upgraded with the latest safety enhancements.  For the first time, crossing gates will be installed, making the Easton and Susquehanna intersection the last of the Regional Rail public grade crossings to have this feature installed.   The intersection of Easton Road & Susquehanna Road will soon have crossing arms, or "gates", to block the intersection when a train passes. Modernization of the Regional Rail infrastructure enables SEPTA to provide more frequent, more reliable train service.  Customers can relax and catch up on some work knowing SEPTA will get them there. A view approaching Roslyn Station.