Fishermen Capsized By Humpback Whale Say They Narrowly Avoided Death

The guys who had a whale land on their boat out in the open seas are luckily fine now -- but in the moment, they saw their lives flash before their eyes ... and we got the full story.

Ryland Kenney and Greg Paquette -- the two friends forced to scramble from their boat after the huge sea mammal landed on the engine -- stopped by "TMZ Live" Wednesday to recount the life-or-death moment ... and it certainly sounds dramatic.

It started out as a regular fishing trip -- but Kenney and Paquette say things quickly went south when the humpback whale breached and came crashing down on their vessel.

Check it out ... the guys say Ryland had a fish on the line when the sea creature crashed down on the boat flipping it -- and them too -- into the water off the New Hampshire coast.

Greg says Ryland -- who was at the back of the boat -- yelled out in surprise ... 'cause he was just a few feet away from the whale's head when it burst to the surface, and while he was first in awe, he soon realized the danger of his situation.

Ryland explains why he jumped from the boat -- and just how lucky he is to walk away uninjured, not to mention alive.

As we told you ... the U.S. Coast Guard told us the incident went down yesterday morning --and, the military branch sent out an alert to other boats in the area. A good samaritan came along and dragged the damaged ship to shore.