A thrill-seeker left suspended in mid-air when the Smiler broke down yesterday said the experience was "horrendous".
The Alton Towers rollercoaster that crashed two years ago reportedly left riders hanging in mid-air for 45 minutes.
A technical fault saw the ride stopped half-way through its loop on Wednesday, June 28.
Towers bosses have said the stoppage was in line with what the £18 million coaster was supposed to do after a "minor technical fault" was detected.
Visitors posted pictures to social media of the stopped ride - with some of those on it stuck in a vertical climb.
One poster who recorded the incident on Snapchat said: "They're stuck again!!"
Another shot showed a technician climbing stairs to get to those trapped onboard while several onlookers recorded videos.
Kate Richard, who was on the Smiler at the time, described the experience as “absolutely horrendous” when talking to The Mail Online.
She said: “They left us hanging for 46 minutes. It took them 15 minutes to use a tannoy to tell us what the hell was going on."
Another image showed a technician climbing stairs to get to those trapped on board while several onlookers recorded videos.
An Alton Towers spokesman said: "At 16.26 yesterday The Smiler experienced a temporary stoppage as a result of a sensor detecting a minor technical issue.
"This was completely normal and what the ride, as well as others, are designed to do at theme parks across the world.
"At no point was guest safety compromised."
The £18 million Smiler is a 14-loop steel-built ride and holds the world record for the greatest number of inversions on a roller coaster.
It was beset by technical problems when it launch in May 2013.
On June 2, 2015, a loaded train collided with an empty test train, causing serious injuries to a number of riders.
Two teenagers - Vicky Balch and Leah Washington - needed their legs amputating after the crash.
Leah's boyfriend Joe Pugh's knees were shattered by the blow while Vicky's boyfriend at the time Daniel Thorpe suffered a broken leg and punctured lung in the accident.
Alton Towers owner Merlin Attractions Operations Ltd was prosecuted by the Health and Safety Executive at North Staffordshire Justice Centre on April 22, 2016, and fined £5 million for health and safety breaches.
