British Airways pilot Captain Eric Moody thought a phenomenon caused by static electricity called St Elmo's fire, was lighting up the windscreen of his Boeing 747, as it flew over the Indian Ocean on its way to Australia.
Captain Eric Moody keeping his cool in a crisis at 36000 feet
As it turned out, the effect was actually caused by volcanic ash from an eruption of Mount Galunggung in Indonesia, sandblasting the outside of his plane!
Not content with giving him a frosted windscreen, the ash went on to block all four engines, which stopped dead at 11,000 metres (36,000 ft).
Luckily, Captain Moody and his co-pilots managed to get them re-started and landed the plane safely in Jakarta, with 263 very relieved passengers and crew on-board.
BBC's Danny Pike hears from Eric how to keep your cool when your engines fail, seven miles above the sea.