With just minutes to spare before morning practice, Hamilton was hurriedly ferried to dry land and he was still jogging to the paddock as the turbo V6 engines began to rev.
"I overslept," he admitted afterwards.
Ferrari's Kimi Raikkonen also had a scare on Thursday, as a Red Bull mechanic frantically pushed him out of the path of Sebastian Vettel in the pitlane.
Meanwhile, Red Bull's Vettel denied reports the RB10 chassis with which he initially struggled in 2014 was found to have been 'warped'.
"There was nothing wrong with the chassis itself," he told Germany's Sky.
"When you set up the car, there are certain measuring tools that we use, and we found that these were not quite right," Vettel revealed.