Date: RBLT 3-93

Conrail rostered a large fleet of coalporter cars. Hollidaysburg Car shops rebuilt old triple hoppers, built in the mid-1960's, into the G52H, G52L and G52R class starting in 1991.
The yellow ends denote that the car was used in one of two Electronic Air Braking System (EABS) Test Trains in 1996. One train had orange painted ends and one had yellow painted ends. EABS applies the brakes to every car of a train simultaneously via an electronic brake signal, allowing a train to stop smoothly in 30-70% less distance than traditional brake-equipped trains.
Each of the two EABS equipped trains had a device called the Head End Unit (HEU) in the lead locomotive of that train. In 'full electronic' mode, which required all cars in the train to be EABS equipped, the engineer used the HEU to apply the brakes. The HEU then electronically and simultaneously transmitted this information via intercar connectors to Car Control Units (CCU), which were mounted on every car's braking system. The CCU's adjusted the brake cylinder pressure accordingly until the HEU issued a different command. Every car then braked the same amount at the same time.
When Conrail finished their testing, they removed the systems from the cars and placed the train back into regular unit coal service. Eventually, the cars were assigned to other unit coal trains and general merchandise service. They retained their orange or yellow ends, with some cars never having their Car Control Units removed.
Some of the G52L class remained in service well into the 2000's, some lasting into 2012.