Crosstie replacement is a vital infrastructure maintenance project, but must be done without disrupting train schedules. In high traffic lanes where work windows are short, Norfolk Southern deploys its “Tie and Surfacing Super Gang”. An army of skilled crew members equipped with high-production, very specialized machines are deployed; old worn out ties are replaced, correct track geometry is restored and rock ballast is properly contoured. This rehabilitation is to be completed in the shortest period of time in order to keep the NS mainline open for traffic. In this program will show this process, identify the unique machines and the procedure to achieve these goals.