Update: DESPERATELY holding onto his 73-year-old father, and trying to save himself, a man clung to his overturned boat for more than an hour waiting for rescuers to find them.
As night fell, the rescue helicopter flew toward Bailey Island, about 46km east of Mackay Harbour. They arrived to find the older man had died, but winched the 40-year-old to safety and took him to Mackay Base Hospital.
The man and his father had spent Thursday fishing in their 4.5 metre open style console boat, Mackay Police said, in what they described as fairly calm conditions, but about 5.45pm they ran into trouble.
"On the way back, the son reported that the boat started to take on a bit of water, nothing overall concerning," Mackay Country Patrol Inspector Steve O'Connell said.
"The dad was bailing out water coming through the bilge on the boat. They don't know what was causing that, they tried to stop it but water was still coming on board."
The boat started to sink as it took water, with the swell from the open ocean making things worse, Insp O'Connell said.
All it took was a shift in weight and a final wave to capsize the boat, causing it to flip and throwing both men into the water.
Insp O'Connell said it took a while for the man to activate the EPIRB as it was trapped in the overturned boat and he had to hold onto his deceased father.
"The man was trying to look after his dad, he's got to duck under the water, go back into the boat, search around with no visibility trying to locate where it's secured on the boat, remove it from its holder and then back to the surface," he said.
Reports from the man in his 40s suggested his father had died soon after entering the water after he suffered a "medical episode", Insp O'Connell said.
Police are yet to determine the cause of death but believe the man's extensive medical condition played a significant part in the incident.
About 20 minutes after activating the EPIRB the RACQ CQ Rescue helicopter arrived at the site of the overturned boat and retrieved the son from the water.
He was flown back to hospital and was treated for cuts, abrasions some possible back injury and hip injury. He could have swallowed a bit of water while trying to keep with his dad and keep afloat, Insp O'Connell said.
He said while there were life jackets on board, they weren't wearing them at the time.
Insp O'Connell said even if they had life jackets, it appeared it might not have helped, given the possibility of the man's medical episode.
Thursday night's tragedy is the second boating accident to occur off the coast of Queensland in the past two weeks.
A trawler carrying seven crewmen overturned in Bustard Bay near Middle Island off the central Queensland coast on October 16.
Ruben McDornan, 32, the only man to make it out alive, clung to the hull of the upturned boat for six hours overnight before a passing vessel chanced upon it.
The bodies of two of the men were brought to the surface on Saturday, while four remain missing.
Insp O'Connell said Thursday night's accident was a tragedy.
"The loss of anyone's life, whether it's at sea or elsewhere, is very hard to deal with and unfortunately we've lost someone yesterday," he said.
"The only good side here is that one person survived and that's due to having an EPIRB on board the boat."
Earlier: A MAN in his 70s has died off the coast of Mackay after the boat he was on capsized this afternoon.
Queensland Police have confirmed a 73-year-old man has been found deceased following a major search and rescue mission near Bailey Island.
Police say the 4.5m vessel containing the 73-year-old and a 40-year-old man ran into trouble around 5.45pm and capsized 25 nautical miles east of Mackay Harbour.
The 40-year-old man managed to retrieve the EPIRB from the upturned boat and activate it while treading water and assisting the 73-year-old man to stay afloat.
BREAKING: A MAN is missing, while another has been saved after their boat sunk 50km off the coast of Mackay.
A rescue helicopter was tasked about 5.45pm after an emergency distress beacon had been activated about 20km west-southwest of Penrith Island.
RACQ CQ Rescue left about 6pm.
On arrival at the scene, the helicopter crew spotted the EPIRB's strobe light in the dark water and found a man, believed to be in his early thirties, clinging to the nose of a submerged vessel.
He is believed to have been on board the boat with his father, who is feared drowned.
Crewman Arno Schoonwinkel was winched down into the water as the helicopter hovered overhead and was able to secure the very distressed man into a strap and winch him up into the helicopter.
The man, who suffered cuts and abrasions, was taken back to the rescue service's base at Mackay Airport where he was later transported to Mackay Base Hospital by ambulance.
It is not known how the accident occurred.
RACQ CQ Rescue and Volunteer Marine Rescue are currently searching for the missing man.
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