It must have been in Phantasialand in April this year. We were on Winja's Fear and after the ride broke down for a couple of minutes while we were waiting. We got on and were almost at the end of the ride where the track suddenly tilts. Before the track would tilt, our car stopped and the next car was coming closer at full speed. The car behind dus stopped pretty fast and working-lights went on. A operator said through a microphone we had to wait a while because there was a defunct on the ride that would be fixed pretty soon.
A couple of minutes later, we saw an operator walking underneath our car and came back with some electric wires in his hand. We never did Winja's Fear before and didn't know what was about to happen and friends who were there with me did start to get scared because the defunct took so long. Than suddenly, without being announced that the defunct of the ride was over, the track tilted and we went down the last hill at full speed.
I can tell you, we did scream out so loud they must have heard it on Black Mamba. The guy in the car behind was laughing before with my friends being in panic, but when the track suddenly tilted, his face became so serious and worried. When we got of the ride we passed him in Wuze Town and he said he really thought we were crashing down to the ground...
The other time was my first ride on Turbine in Walibi Belgium, 7 years ago. In Belgium, this ride is pretty much known as the ride that got stuck upside down for an hour and a half. I remember us standing in the very claustrophobic corridor before you get into the station. Pumping technobeats made the walls move and than you hear this loud noise from the train being launched. Walls and floor were shaking and we heard people screaming so loud...three of us just went straight to the exit, because they were so scared. I did like the ride but everytime I get out the ride I think...thank god we didn't get stuck in this huge looping!