5011 is the lead of 11 engines at the East end of the yard.

Southbound Below Sunbury With a freight in the afternoon sunlight , notice the rusted and peeling paint on lead engine , it looks like its time to get this engine serviced

NS 5011 and SR 3512 lead this e/b. A GP-38-2/B-30-7A lashup. On NS, these units must be considered "back to back". 30APR88