The contrast between a big northern amusement park’s back lots in January and a summer operation day is so striking that it almost seems strange. It’s empty in the middle. There are no longer any lines. The brake fins and transfer sections of coasters that were operating sixteen hours a day six months ago, transporting thousands of riders through inversions and up lift hills at sixty miles per hour, now have snow on them. The trains are not actually on the tracks. It has been weeks since they last did. They are somewhere else totally, within, disassembled, and in different stages of being broken down into their component parts.
Before the worst of the weather arrives, a park in the north of the United States starts its off-season demolition. Maintenance teams begin the removal procedure after the last train completes its final circuit and the last operating day has passed. Small overhead cranes or lifting equipment placed into the repair shop access areas are typically used to separate individual cars from the circuit and lift them off the station or transfer track sections. It is crucial to remove the trains from the track before the freeze-thaw cycles start in earnest because ice and increasing moisture in joint connections produce issues that are much more challenging to resolve in the spring if the components have been left exposed for the whole winter.
The actual job starts once you’re inside the maintenance bays. The wheel assemblies—the polyurethane road wheels, guide wheels, and upstop wheels—come off first. They must all undergo individual inspections before anyone decides to continue using them for a further year because they absorb a significant amount of cumulative stress during an entire operating season. Lap bars, over-the-shoulder harnesses, and the pneumatic or hydraulic devices that power them are the next restraint systems. A train’s mechanical connections between cars are inspected for wear indicators that may not have been apparent during in-season walkarounds. Finding every microcrack, worn surface, and component nearing the end of its useful life before the park reopens, as opposed to during operations, is the aim at this point.
In most well-run facilities, non-destructive testing is a standard component of this procedure. In steel components that appear perfectly normal on the surface, subsurface cracks and material fatigue can be found using magnetic particle inspection and ultrasonic testing. The entertainment business has been using the same technology used in heavy manufacturing and aerospace for long enough that skilled maintenance teams are at ease analyzing the results and choosing replacements based on them. Inspection-failing components are not reinstalled. Unlike decisions on cosmetic repairs, for example, the criteria for what qualifies as a pass are not negotiable.
The mechanical disassembly is preceded by the cosmetic work, not the other way around. Older coaster cars’ fiberglass shells wear during the course of a season, causing surface cracks, paint fading, and minor impact damage from debris. Repairs are made during the winter window. The scheduling usually occurs in parallel rather than sequentially since repainting an automobile when it is completely disassembled is more simpler than working around installed components. During this time, hydraulic and pneumatic systems are not only inspected but also rebuilt. A rebuild during the off-season avoids the kind of mid-season hydraulic failure that would pull a ride out of operation on a busy Saturday in July. Seals, cylinders, and pressure components have predictable service periods.
