The Vekoma Boomerang. The my first coaster starter kit. The most popular six inversion catalog coaster of all time. With over 50 installations world wide since 1984 you need not travel far to enjoy a ride that simulates what its like to ride inside a washing machine loaded full of bricks. Being a massively produced ride you would think that over the last 30 years that they perfected the design. Hey, One can dream right?
It's a hot summers eve just before sundown, evening thunderstorms are on the way. In my second season as an area supervisor. Our modern marvel of an attraction, sponsored by Advil, is operated by two of the dumbest human beings the earth has ever seen. At the MOP is a blonde chick who we will simply call Shelby, and at Load is a stoner who we will simply call Eusless. Shelby got trained on this ride because they felt she was two stupid to safely operate a kids ride, and Eusless landed the gig because the start of season lottery.
Now it's important to note that this attraction is not one under my purview. In fact, it's on the complete opposite side of the park from my responsibilities. Which is good, because I am afraid that stupidity might be a contagious epidemic in theme park employees. I am sitting in the employee cafeteria, radio on, eating dinner with some good friends in maintenance. Sharing our greatly exaggerated stories of the days events with many vibrant expletives tossed in there for good measure. I overhear on the radio that the spotters are reporting lightning in the distance and that we would start securing rides as it got closer. I think, just what we need, another night of violent thunderstorms so we can all go home early to come in early to push water around.
As soon as I am about to leave the cafeteria the lights go out. Only emergency lights are on. Sh*t. When the power goes out we also loose radios, but we don't loose phones. So I run to the kitchen and grab the park phone and frantically start calling all 20 of my attractions. Do you have units stranded or unreachable? Do you need assistance unloading? Can you clear all guest? I got lucky, nothing stranded and everything was basically in a home position. So I do the honorable thing and call dispatch, advise them we are clear, and how can I help. They tell me that Josh hasn't checked in, and to start calling his rides. Uh... sure. Now lets be honest, if you put a name tag on a guest with special needs you would get Josh.
So I start calling his rides, and I get to the last one which isn't answering. After about 5 minutes of ringing I just decided to walk the 4 minutes across the park to go punch someone in the face. Sure enough as I get close I see a bunch of guest looking up out our modern marvel which hasn't a single external light on. The pointing, the joking, the deer in the headlights expression on their faces. Yes folks that is a unit half way stranded on lift two. No I don't know when it will be fixed. Up to the station I go, to the MOP to see whats on the board.
Now in bold print in the SOP is a line that says if the power goes out, you press the big red button and don't think twice about doing it. The reason for this varies from ride to ride, but generally adding and removing power to the controls system can cause them to do funny things. In the case of legacy relay logic systems, it deenergizes all the relays so they reset to a safe position. Otherwise they would get stuck in a position that when power is restored is out of sequence. Before I can get to the MOP to press the E-Stop the power comes back on. I reach the MOP just in time to watch the train climb 10 feet more up the lift then roll backwards through the loop and park itself in the saddle in between the cobra roll.
You see in relay logic you have a series of relays which in turn interlock with other relays to enact a specific sequence of events. Unlike PLCs, they are designed to only be operated in that specific sequence and cannot be readily put back in sequence or reset with out powering down. As I would later learn from the electricians when the power went out, Shelby saw that the unit was stranded and decided hitting the lift stop button was a good idea. When nothing happened, she saw the button that said "Lift Two Release" and pushed that. Since the hydraulics were operated by a valve that required power, they held until power was restored. Since those relays were de-energized by canceling the sequence with the buttons, the hydraulics cut off releasing the track pan, and the lift cut out as soon as the contactor opened up. As part of the lift two release sequence, the brakes at the bottom of the hill are energized and opened up.
"Oh, that's neat. Why don't you just unload it using the handy dandy cat walk?" - Because that catwalk hadn't been invented yet. In fact it wouldn't be invented for two more years until another incident where a boomer stranded a unit in a similar manner that I believe resulted in some litigation. So what does a young supervisor do when a situation like this happens? Well, first he calls the maintenance supervisor, to give him a 2 minute head start on sourcing ladders and people. Then he calls operations to tell them we are going to need to call the fire department because nothing we have on hand can undo this predicament. Then he calls security to see if they can dispatch some people to start clearing the way to get the fire truck in. After that he starts yelling to the people that it's going to be alright and to not mind the big flashes of light looming in the distance and the rush of cold air that means rain is on the way.
After about 15 minutes the fire department shows up, takes one look at the situation, and posses the question. "So what do you want us to do?" Now up until this time no one thought it would be a good idea to keep the fire department in the loop on how to handle these situations. So the book was being written as we were going along. Step 1, cut down the fence surrounding the ride so the fire department can get the ladder truck in. Step 2, go press that fing E-Stop. Step 3, disconnect the power. Step 4. Excessively tie the train down to the track because maintenance has no idea how much a unit weights. Step 5. Unload back to front. Step 6. Apologize to the guest by handing out coupons for free ice cream, drinks, and multiple year season pass books.
In the end it took 4 hours to unload the ride and 3 days before it went back into service. The train had to be craned off and reassembled at the base of lift two. Maintenance did accept my recommendation to install a gate wide enough to accommodate a fire truck, it was promptly made useless after two seasons when another attraction was installed. Good thing too, because the second time someone stranded a unit it was between the loop at the cobra roll exit. It never did rain, but the weather did distract the media enough to keep them far away from our park. Shelby was relocated to park services and later fired, turns out operating a broom and dust pan was also too complicated for her. Eusless disappeared shortly after the fire department arrived. He never showed up to work again and got terminated for no call no show.
Edit: Just so we are clear, ride elements are: Lift 1 (Backwards), Station, Cobra Roll, Loop, Lift 2 (Forwards).