Saturday, April 21, 2012
53.1 Conemaugh Line Freeport to Bolivar
The severe curvature in the vicinity of Freeport, PA on the Conemaugh Line could be reduced to 2 degree curvature allowing a maximum 80 mph speed. Reducing curvature and restoring the second track would allow for future freight capacity. It would eliminate the slow and circuitous routing of freight over the Port Perry Branch to the Mon Branch. Increasing speed and track capacity on the Conemaugh Line would overcome the conflict between increased passenger service and the crossing of slower freight trains to and from the mainline at Milepost 339.5 in the vicinity of Wildmerding for access to the Port Perry Branch. The Conemaugh Line has a favorable ruling grade.
The existing line in yellow supports a 30 mph freight speed. The curvature approaching Freeport and through Kiski Junction to milepost 46.6 varies from 4 to 3.5 degrees. Rebuilding the line in blue would be the equivalent to a 2 degree curve capable of 80 mph.
Where is the 80mph coming from?
ReplyDeleteIn the tables from the latest update to the FRA superelevation and cant deficiency regulations, a 2deg curve is balanced for 60mph operation with 5 inches superelevation. If a FRA-compliant Talgo was used, 6 inches of cant deficiency would be 89mph.
Its higher with greater superelevation, but I'd assume an express freight cutoff would be balanced for 60mph heavier freight operation, with possible rapid freight and an allowed 3" can deficiency yielding 76mph.