Friday, May 30, 2008
Nearly a year after the original incident, the Kentucky Department of Agriculture has released a report [PDF] summarizing its investigation. Some quick initial reactions:
The overall conclusion is that the agency can't pinpoint a single cause, but they focus on the cable condition (necessarily implicating the park's inspection program and, less clearly in this report, the Department's own inspections) and on the ride operator's failure to hit the emergency stop immediately upon hearing the problem noises. (The operator's explanation for that decision is below.) The park will be fined a whopping $1,000 for failure to maintain the ride; the agency is not seeking criminal sanctions.
The ride had been inspected earlier in 2007 (apologies for weird formatting):
For the 2007 inspection, the KDA inspector spot checked the cables on sections II, III,
IV, and V. The cables on section I had been replaced with new cables prior to the
inspection. Because t he STP was presented to the inspector in operational condit ion, the
spot checks on sections IIV were conducted with a leather glove, due to the volume of
grease on the cables. The inspector determined a rag test would not be useful during this
particular inspect ion because the grease on the cables would quickly fill the rag with
grease, making broken wire detection impossible. The spot checks were performed wit h
the drums and sieves operating at low speed in maintenance mode. Even with the drums
and motors running at low speed, this inspection is extremely dangerous for anybody who
places his hands on the cable because of the possibility that the person’s hand may get
caught in the drum. The inspector did not find cable breaks on any section of the ride.
The report later notes that the Department of Agriculture did not have the same inspection directions from Intamin that Six Flags did.
Upon inspection after the incident, the Department of Agriculture inspector concluded that the cable looked different than when the same inspector had examined the cable a couple of months earlier -- it was significantly deteriorated. (As a potentially incidental aside, ride inspectors in Ohio were criminally charged a couple of years ago when they failed to check electrical grounding but indicated on their report that they did so.)
The report also includes synopses of the interviews with the ride operators. The main ride operator evidently first called the park emergency phone number rather than hitting the emergency stop button when things looked like they were going wrong. Why? Her explanation:
When asked by the KDA why she did not hit the Estop before being prompted to do so,
the MainRide Operator stated that she made a deliberate decision not to hit the Estop.
She said the cable was swinging, and she thought if she hit the Estop the cable might cut
persons on the ride.
(Incidentally, both ride operators were under 18. Kentucky has now adopted a requirement that operators be 18; perhaps someone with a little more experience would have hit the e-stop first. That at least seems plausible and may put to rest some of the criticism of that legislation.)
The cable was eventually analyzed by an outside lab; the Agri Department retained an expert to interpret that report. The bottom line is that the cables failed due to garden-variety fatigue. Here's the money quote, in response to an inquiry about whether the problems could have been prevented:
The extent of progressive (fatigue) cracking would have made it possible for the
park personnel to detect the deteriorating condit ion of the rope had they been
following the inspect ion instructions given in the maintenance manual.
The initial report from the Courier Journal is here. More to come next week, I'd imagine.