The Duke of York will abseil down the Shard skyscraper in London for charity today.
Other participants include Ffion Hague, the wife of Foreign Secretary William Hague, and leading businessmen and women.
The Shard is the tallest building in Europe, and its viewing galleries will be open to the public in February next year.
A spokesman for the Shard said: "The wind got up a bit more than we were anticipating.
I think it was seen from a helicopter and people panicked unnecessarily.
Three workmen were still working on the London Bridge Station side of the Shard this afternoon, having come down as far as around the 25th floor. The trio could be seen slowly descending down the side of the glass-sided building, washing the windows as they went.
There were no signs of them being in any difficulty despite blustery conditions around the skyscraper."
Witness Neil Walsh was waiting for a train at nearby London Bridge station when he saw the drama unfold.
The 30-year-old marketing executive from Dartford, Kent, who filmed the incident on his phone, said:
A video posted on YouTube shows how a cradle became stuck outside the tallest building in western Europe - The Shard.
At the top of the picture, the cradle can be seen swinging in the wind. It became stuck outside the 72nd floor, high above London. Engineers eventually fixed it.
Emergency services were sent to the Shard - days before its official opening - after a cradle got stuck in a precarious position on the 72nd floor.
Ten firefighters attended the scene in central London after reports of the cradle on the outside of the building becoming unsafe.
On-site engineers fixed the problem. An ambulance was on standby at the bottom of the 309.6 metre (1,015ft) high building.
London Fire Brigade, which sent a fire engine and fire rescue unit to the Shard, said on Twitter: "On site engineers at the #Shard have made the cradle safe".
The Shard, the tallest building in Western Europe will be opened by Qatar's prime minister and the Duke of York on Thursday.