Katonah Fire Department's Ladder 39 was dispatched late yesterday afternoon to stand by for Somers Fire Department while it was fighting a structure fire on Shenorock Road. Joined by an engine from Golden's Bridge FD, Ladder 39 stationed itself, along with Car 2211, at Somers' Lincolndale Fire House, ready to cover any other alarms that Somers might receive while its resources are committed to the fire. A key component of the mutual aid system is having the ability to call a neighboring department and having it provide apparatus to cover the home district while its resources are committed to a major event.