Australian swimmers have set another world record while harvesting three more gold medals to equal the nation's largest haul at a world championships.

Australia's world record in the mixed 4x100 metres freestyle relay followed Cameron McEvoy becoming the nation's oldest world champion and Kaylee McKeown completing a rare golden backstroke sweep.

McEvoy won the men's 50m freestyle on Saturday night in Japan and McKeown collected the 200m backstroke crown after earlier wins over 50m and 100m.

The mixed freestyle relay team of Jack Cartwright, Kyle Chalmers, Shayna Jack and Mollie O'Callaghan added an exclamation mark to capture Australia's 13th gold in Fukuoka, equalling the nation's record haul at the 2005 and 2001 editions.

The Dolphins will top the medal table at these worlds, which finish on Sunday night. They're eight golds clear of China, with seven finals to come.

The last time Australia topped the tally at the worlds was 2001, also in Fukuoka.

"It's always something that is probably in the back of our minds and it's something that gets spoken about quite a lot in the media, us leading the medal tally," Chalmers said,

"And it's something Australia was able to do in Fukuoka back in 2001 so to do that again and be a part of one of Australia's most successful teams is inspiring."

Australia have set five world record at this meet with O'Callaghan involved in four.

The 19-year-old created a 200m freestyle record and was involved in Australia's benchmark relays in the women's 4x100m freestyle and 4x200m freestyle.

Now, she's part of a mixed 4x100m freestyle relay team which saluted in three minutes 18.83 seconds, inside the nation's previous record of 3:19.38 at last year's worlds.

On Sunday night, O'Callaghan could equal Ian Thorpe's Australian record of six gold medals at a single world championships created in Fukuoka in 2001.

"I'm too busy to think about it, to be honest," O'Callaghan said.

Her latest achievement came as 29-year-old McEvoy, the oldest Australian to win a world championship, turned conventional swimming wisdom on its proverbial head.

McEvoy said his win proves elite swimming isn't just for young athletes and justifies funky training methods featuring rock climbing and callisthenics rather than endless laps of the pool.

"Hopefully, our different training methods feeds back into the swimming community," McEvoy said.

"And either gives older guys a little bit more longevity in the sport or allows others to hit their potential when they may not have necessarily hit it."

McEvoy clocked 21.06 seconds to triumph some 11 years after making his first Australian senior swim team, while compatriot Isaac Cooper (21.70) came fourth.

McKeown completed her golden sweep, winning the 200m title in 2:03.85 following her 50m and 100m triumphs.

"That means a lot, I didn't think I would be able to do that," she said.

In the women's 800m freestyle final, American legend Katie Ledecky (8:08.87) cruised to her sixth consecutive world title - a record for any event - with Ariarne Titmus (8.13.59) third and Lani Pallister (8:21.33) seventh.

Australia's Matt Temple (50.81) finished fourth in the men's 100m butterfly final.

In the women's 50m freestyle semi-finals, Jack was second-fastest into the medal race with a personal best 24.01 as Sweden's Sarah Sjoestroem set a world record of 23.61.

Emma McKeon (24.67) was seventh quickest into Sunday night's final while, in the men's 50m backstroke, Isaac Cooper (24.86) was ranked ninth to just miss the medal race.

© AAP 2023

Gold Coast have turned the tables on their long-time bullies, a tenacious Touk Miller inspiring the Suns' first win over the Brisbane Lions in five years to dent their AFL neighbour's top-two plans.

The Suns kept their own finals hopes alive - they need to win their remaining four games to make the top eight - and interrupted the Lions' hopes of jumping Port Adelaide into second place with a 15.6 (96) to 7.13 (55) pummelling in Carrara on Saturday.

Marcus Ashcroft Medal winner Miller (29 disposals) went old-school with a hard tag to run Lachie Neale (17 touches) into the ground, while under-fire forward Ben King was back to his best with an equal career-best five goals.

Brisbane trailed by three at halftime, 17 at the final break and scored just seven points in the fourth term as the Suns out-tackled and out-ran the premiership hopefuls.

It broke a nine-game Lions QClash winning streak and cost Chris Fagan's men the chance of finishing the round in all-important second place.

"You can't allow teams to push and shove you around and get the wood on you," interim coach Steven King said.

"Our playing group had had enough of honourable losses and coming up short.

"It's bigger than just four points; it builds belief. When we're connected for four quarters that's the result."

Sam Flanders (32 disposals) had another big night and Noah Anderson (29 touches, one goal) was a chief destroyer for the interim coach, who leant on his horror author namesake to script a nightmare for his opposite number.

Miller demanded the job on Neale and blanketed the Lions' Brownlow Medallist in the first quarter, restricting him to just two disposals.

Delivery was of the finest order to King, who broke a month-long goal drought and had three at the main break and take influential Lions defender Harris Andrews out of the game.

Josh Dunkley had 30 touches and 10 tackles but Brisbane had no answer in the final quarter, Matt Rowell winning a forward clearance, shrugging a tackle and snapping a terrific goal.

In a further blow, in-form Lions defender Keidean Coleman was taken to hospital after an accidental knock to his eye.

Fagan said he'd need to review the game before commenting on how the side could have better handled Neale's close attention.

"The one thing going well was contested ball and clearance, but we got beaten up in that area in the second half," Fagan said.

"We've been so good for the last six weeks in that department. But we were beaten up by a team that was super hungry to get the job done.

"It had built up and you could tell by their reaction ... how much it meant to them."

Victory kept the Suns' mathematical hopes of a maiden finals appearance alive a month after sacking head coach Stuart Dew.

To feature for the first time they'll need to beat Adelaide, Sydney, Carlton and North Melbourne to finish the regular season.

© AAP 2023

Captain Sam Kerr has declared herself available to play in the Matildas' do-or-die Women's World Cup match against Canada in a massive boost to Australia's precariously placed campaign.

But just how many minutes the superstar striker will, or can, manage remains a mystery.

Kerr, Australia's all-time leading scorer with 63 goals in 121 games, injured her left calf the day before the Matildas' opening game against Ireland and hasn't played since.

The 29-year-old put the boots on for the first time since her injury at Saturday's closed training and subsequently confirmed her availability.

Australia's campaign is on a knife's edge after Thursday's 3-2 loss to Nigeria and the Matildas realistically must beat Canada to guarantee progression to the round of 16, without relying on Ireland to beat the Super Falcons.

Kerr, who had put herself forward to speak to the media, wouldn't be drawn on exactly how many minutes she could handle but when asked to clarify if she would be fit to play if selected, said: "Yes".

"I feel good. The plan has always been the same, miss the first two games and then reassess," she said.

"I'm feeling good. I was out on the pitch today. As good as I can be.

"I would love to tell you guys everything but ... that's a massive thing that the opposition wants to know.

"It's going to be down to the wire - I'm definitely going to be available but how we decide to use that is not to be given to the opposition."

Fellow striker Mary Fowler, who missed the Nigeria loss with concussion, should also return.

When asked how Kerr looked on the track, defender Ellie Carpenter said with a smile: "Like Sam".

Kerr joked she'd been stunned by the setback as she had "the biggest calves in the world" but had quickly moved on.

"I've never had an injury like this in my career. I mean, touch wood this is the last," she said.

"Normally when I've been injured it's been really a big one where I've been out for months on end, so it's an easy pill to swallow, but with these ones it's a bit more annoying.

"It was obviously disappointing and then I had to kind of suck it up. I'm part of a team. I'm not a part of an individual sport.

"It's not about me, and that's what I've done over the last however many days it's been - I've had to put the team first.

"I've enjoyed being on the other side and realising how important it is, the role you play from the bench. If anything, it's given me a new perspective on this whole team sport and how it takes a whole team."

Kerr opened up on the long, hard days of rehab, which regularly stretched from early morning until 4pm.

"I've done everything I can and no matter what happens, I know that I've given everything, not just in the last 10 days, in the last four years, I've given everything to be here," she said.

The Matildas (three points, goal difference 0) sit third in Group B behind Nigeria (four points, +1) and Canada (four points, +1).

© AAP 2023

A couple in their 60s are dead and a pilot has escaped without serious injury after two light planes collided midair at an airfield in regional Queensland.

The Australian Transport Safety Bureau is investigating the crash, which happened when a Jabiru J430 was taking off from one runway while a Piper Pawnee was landing on a crossing runway at the Caboolture aerodrome, north of Brisbane.

Several fire and and ambulance crews responded following the "significant incident" about 10.30am on Friday.

The man and woman in the Jabiru suffered fatal injuries and the other pilot, believed to be in his 70s, survived with minor injuries.

Police Superintendent Paul Ready said the collision occurred "low to the ground" at the eastern end of the airfield.

"It is an incident between two planes that has been a loss of life which is tragic," he told reporters.

Supt Ready said the surviving pilot was assisting investigators and was "probably quite lucky when you look at the damage on the ground".

Queensland Ambulance Senior Operations Supervisor Matthew Davis described the scene as "incredibly confronting".

"Any incident involving the loss of life, particularly under these circumstances, is extremely, extremely difficult and hard, obviously, for the first responders and most importantly for the family," he said.

Police Minister Mark Ryan said the crash was "so sad on many levels" and a full investigation would follow.

"Caboolture Airfield is a very busy place. There are a lot of people there and obviously there will be people impacted by witnessing this event, so there will be support provided for those people as well," he told reporters.

ATSB investigators were at the scene on Friday afternoon and additional investigators from Canberra will arrive on Saturday morning.

Chief Commissioner Angus Mitchell urged anyone who witnessed the accident or had video of either plane during their flights to come forward.

The airfield caters to general aviation and ultralight aircraft and is not controlled by Airservices Australia.

A spokesman confirmed the aircraft involved were registered and not linked to the gliding club based at the airfield.

Caboolture Airfield was also the scene of a horrific crash in March 2014 when a single-engine skydiving plane crashed during takeoff, killing all five people on board.

In another midair collision in southeast Queensland, a glider and ultralight aircraft crashed midair above Kybong, near Gympie in November, killing both male pilots.

© AAP 2023