The #8 double slip is now built with moving frogs in the center to eliminate potential problems with off-center wheel-sets trying to take the wrong route. It requires two extra switch machines. Shorter slips don't have this problem, and all are built with fixed frogs.
The #8 double slip is now built with moving frogs in the center to eliminate potential problems with off-center wheel-sets trying to take the wrong route. It requires two extra switch machines. Shorter slips don't have this problem, and all are built with fixed frogs.