It took around 30 hours for emergency teams to be able to reach Philip Goodeve-Docker's team and airlift them to safety but Mr Goodeve-Docker died before their arrival.
The London events manager was on the unsupported crossing with experienced expedition leader Roan Hackney and Andy Norman, a former IT professional, who both remain in a "critical condition" in hospital.
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One of the youngest victims of the Grenfell Tower tragedy choked to death on fumes from the fire, an inquest heard.
It should remain dry through the evening with the best of any clearer intervals in the east.
Huge plumes of smoke could be seen for miles above the London skyline as two fires burned in Canary Wharf and a scrapyard in east London.