WA ocean paddler rescued by submarine

It sounds an unlikely tale but an West Australian ocean paddler can now boast he was rescued from the ocean by a submarine.

Retired aid worker Ken Dinham got into difficulty during a race between Rottnest and the coast on Saturday and believed he would have died if not for a sharp eyed submariner.

The 71-year-old, who with his partner Fran Siversten, now lives and works in Vietnam nearly didn't make it.

Ken Dinham is lucky to be alive after getting in trouble during an ocean paddle boarding race. Photo: 7 News

Visiting his two sons in Perth, Mr Dinham entered as a competitor in what organisers call the Doctor.

It's the world's biggest downwind paddling race, 27 kilometres from Rottnest Island to Sorrento beach.

At the 11 kilometre mark Mr Dinham was hit by a big wave and knocked from his ski.

The event is a race between Rottnest Island and Sorrento beach.

It was all downhill from there his leg rope snapped so he reached for his emergency flare.

"When I pulled the flare the cable came straight out of the flare and absolutely nothing happened," Mr Dinham said.

Mr Dinham thought he was alone... until he spotted an Australian submarine.

Mr Dinham's partner said she and his sons were starting to panic on the shore when he didn't emerge from the water.

"I could see them, but how could they see me?" Mr Dinham said.

But a sharp eyed member of the crew had spotted Ken and the sub changed course to check his welfare.

"There's the Australian navy within a 150 metres off me and a rescue boat. I just could not believe my luck."

There are a string of safety measures surrounding the annual race.

Mr Dinham was taking part in an annual 27 kilometre race when he got into trouble.

High visibility hats and lifejackets, leg ropes, flares and several safety boats are all used.

Competitors are counted into and out of the water but Mr Dinham's concern was he wouldn't be missed until the end of the race and then it could have been to late.

Luckily a keen-eyed submariner spotted the 71-year-old in the water.

Fellow competitor Brett McDonald said: "When you lose contact with your craft you become a swimmer and you are very hard to see in the ocean".

Mr Dinham's partner Fran Siversten said she and his sons grew concerned when they didn't see him coming out of the water.

"I consider myself a very lucky man and a very happy man," Mr Dinham said of his miracle rescue.