The Reverse Cowgirl, designed by college students, "dropped its riders vertically, then turned them face down as they skimmed 2 feet above the ground, face down and strapped with their backs to the cart." Suddenly Six Flags seems so safe.
The Cowgirl, built for a rush event at MIT, is equal parts impressive and terrifying. Look at it! Whenever I'm on a real roller coaster, I always reassure myself that professionals are responsible for designing, constructing, and monitoring these things and figure that thousands of people have been on them before me without incident. Can't really do that with this one!
This photo is ominously captioned:
The cart in motion (the rider is hidden underneath)
Underneath!? Yikes. But from a Flickr comment presumably left by one of the students involved with the homebrew coaster,
it sounds like someone either ended up a pancake in one of the first runs or saw the potential for danger in a complicated wooden rollercoaster built by a bunch of 20 year olds and shut it down:
It was not a fail.. It had 20 people ride it. Sure, not 200, but you try building a roller coaster that complex in a week.
Update: Mike, the designer of the Reverse Cowgirl (the rollercoaster), writes that no humans were pancaked as a result of the coaster and that their construction, as you can imagine, is reviewed extensively.
Each year, we build a roller coaster or similar ride in our courtyard, and each year, there is an intensive safety approval process we go through. Nobody has been injured on these rides (at least as far as institutional memory goes), for if somebody were injured, this would never be permitted to happen again. We build the structures using the appropriate safety equipment, and conduct thorough testing of the ride before putting anybody on it.
The reason 20 people rode this roller coaster is that we have a very narrow window in which to construct the roller coaster, use it, and tear it down. We cannot start construction before we have enough students back on campus to participate in the construction. We must also tear down the roller coaster before the semester starts, because it is understood that it is a temporary structure, and when the semester starts, everyone is too busy to take it down. Incidentally, we had to take the coaster down a bit early this year due to severe weather warnings. We did not want to endanger anybody's safety, so rather than trying to tough out the storm, we elected to destroy the coaster in a controlled manner (as opposed to letting the weather do it in a less controlled manner). Because of the complexity of the coaster (notice, it goes completely vertical; something we have never attempted before), and due to inclement weather during construction (it poured for three days straight, which takes a big chuck out of a fourteen day window), we were unable to open the coaster for more than two days of operation. Additionally, due to the rider being strapped to the bottom of the cart, with their face low to the ground, we took extra precautions to secure the rider, using full 5 point safety harnesses, a helmet with head restraint, as well as arm and leg restraints. This meant it took 20-30 minutes to load one person safely into the cart and check all of their restraint points for safety and comfort. Hence, only 20 people got to ride this year.