Dozens were stranded upside down in midair - having to literally hang tight and wait for the problem to be rectified.
Last month, a horrific crash at the theme park led to 16 people being injured - four seriously - and two girls had to have a leg amputated each.
Following the crash on the Smiler ride in May, the park said it would introduce stricter safety procedures.
No injuries have been reported from this latest glitch at Alton Towers, but it will no doubt do nothing good for the public image of the park, which has been greatly damaged by recent incidents.
Meanwhile on the same day, brave victim Vicky Balch, who lost her right leg below the knee in the crash, has shared her first picture since the horrific incident.
The 20-year-old took to her Twitter to share a snap of her and Major Kate Philp, who lost a leg fighting in Afghanistan but went on to trek to the South Pole will Prince Harry.
Alongside the picture, Vicky wrote: ‘Today I was inspired by a very amazing woman Major Kate Philp and I hope one day I can so the same for somebody else.’