Mine Ride's old control system was entirely manual and had no less than six blocks on it. All of the station braking was done by hand; a very simple logic system handled the block brakes (in fact as you started up the ramp into the station you could look over at the block brake uptrack of the tunnel where a sign indicated the two brake pressures for "trim" and for "stop"; a system of solenoid valves took care of figuring out which would happen when the train arrived on that brake. But I am getting ahead of myself.
A few years ago, at a particularly inopportune moment, somebody made a terrible mistake and caused Very Bad Things to happen with a couple of empty trains. I won't elaborate, though I am sure you can figure it out, and I won't name names except to say that it was NOT a seasonal employee. As if the incident wasn't bad enough, a Very Important Person Not Employed By Cedar Fair happened to be watching when it happened.
Mine Ride never again ran three trains in revenue service with that control system. The result was long waits for a couple of seasons. Then for the 2000 season, Consign AG designed and installed a completely new control system for the ride. Now the lifts have variable speed motors, the two block brakes are gone, and the brakes are a modern canister style. With the new computerized control system, the ride can once again run three trains. It can no longer run four or five because the block brakes have been removed.
BTW: I verified the disaster story separately with both that year's ride foreman and with the aforementioned Very Important Person.
--Dave Althoff, Jr.