Pilot captures moment huge shark stalks NSW paddleboarders

A pilot conducting an aerial survey of a beach on the NSW Central Coast has captured the moment a huge shark came within metres of a group of paddleboarders that included his brother.

Commercial aircraft and drone pilot Thomas Caska was testing his hi-tech equipment at Kilcare Beach on Tuesday when he spotted the giant predator stalking a school of fish.

Mr Caska said his brother Andrew had told him the conditions were "sharky" that day and he thought he had spotted a dolphin.

But when the pilot got home and reviewed his footage, he saw the massive shark.

Mr Caska told ninemsn the chilling image came as "a bit of a shock".

"It's the biggest shark that I have ever seen," Mr Caska, who has been a surfer his whole life, said.

"It was probably in the 4m range.

"The good thing was it was more interested in the fish than anything."

Mr Caska said when he showed the photo to his brother he "had a heart attack".

"My brother couldn't believe it," he said.

"He thought it wasn't real.

"I've been surfing with him a few times, we've seen sharks and pretty close but nothing that big."

The aviator said the shark could have been a great white.

"Broken Bay, which is nearby, is renowned for having great whites cruise in and out," he said.

"A fisheries guy told me he had seen a few in the area."

Despite the close call the drone entrepreneur said the whole experience was "comforting" and added that he would continue to surf at Kilcare Beach.

"If anything it gives me more confidence that we can live in harmony with the species," Mr Caska said.

"It had every chance to eat the other guy or my brother but it didn't."

Mr Caska is currently setting up a drone company called Aerolens that will offer aerial surveying and cinematography services. And even though his shark spotting was purely accidental he believes that unmanned aerial vehicles offer a good way to monitor shark movements and he plans to explore drone shark patrols in the future.

"The technology is so new the potential is enormous," he said.