Thorpe Park's new roller coaster, The Swarm, stalled on its very first day - leaving passengers stuck for several minutes.
One onlooker told the BBC that people were left waiting in the middle of an ascent, while staff assured them over loudspeaker that they were "perfectly safe".
The Swarm ride has been described as Europe's tallest winged roller coaster and the Surrey theme park's "most extreme ride to date".
But unfortunately the setback occurred on Thursday, the very same day the ride was launched.
A Thorpe Park spokesman told the BBC: "The Swarm is a sensitive piece of equipment and a small problem resulted in the fail-safe system shutting it down. Health and safety is our main concern.
"Our engineers were on site to rectify any teething problems. It was back up and running within minutes."
Apart from the teething problems, the ride is likely to be a huge hit, and was even described by an ex Red Arrows pilot as "gut-wrenching".
The UK theme park drafted in four fighter pilots to be the first humans to ride the winged roller coaster, which also recently made headlines when crash test dummies returned from a whizz round - with missing limbs.
It is the UK's first winged ride - with thrill-seekers sitting either side of the track - and also features 4D rotating seats.
You'll fly through the air at 100km hour, and the post-apocalyptic theme will take over the whole island, with an overturned big rig truck, a destroyed television satellite truck, and shipping containers doubling as shops, foot stands and toilets.
And the ride itself nose-dives through a backdrop of devastation, including a crashed airplane, a burnt-out fire engine, and a smashed-up helicopter, with the ride station being a demolished chapel.
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