This amazing video is a reminder of just how fast a boat can sink. As rescuers approach a floundering fishing vessel, it makes a final plunge to the bottom of the sea - it just shows how essential it is to wear your lifejacket!
The fishing boat, the Snowdonia, sank rapidly after it began taking on water in the Irish Sea. Two fishermen from County Down were rescued by another vessel, the Tribute.
"We just went up on a wave and the back of the boat went into the water and she just never came back - she just went down that quick," said captain Stephen Kearney. Rescuers managed to drag the crew aboard, and they were eventually airlifted to hospital by the Irish coastguard.