The £44m cable car line, which crosses the River Thames in east London to deliver visitors to the London 2012 Olympic Games, ground to a halt as outside air temperatures hit near 31C.
Passengers were left dangling in mid-air for 40 minutes while officials battled to get the cars back up and running.
Though the cars are air-conditioned, doubtless some visitors will be looking to get their £16 ticket refunded.
Transport for London has launched an investigation into the blunder, but reportedly denied it had anything to do with a generator overheating in the summer weather.
Head of Emirates Air Line Danny Price said that all passengers were offered water and first aid upon disembarking.
The service links the O2 arena in Greenwich – hosting London 2012 basketball and gymnastics events – and the ExCeL exhibition centre at the Royal Docks, which is hosting Olympics boxing and a raft of other sports.