A kite surfer suddenly lifted into the air by a southerly breeze and dragged through bushes and a fence nearly "peeled off half his face" when he slammed into a street-sign pole on the weekend, a Sydney lifesaver says.

The 48-year-old Woy Woy man - whose name was not known - had surgery for facial fractures and a blood clot to the brain after he lost control of his kite at Sydney's Ettalong Beach about 4.30pm on Saturday.

He was in a stable condition at Royal North Shore hospital, a hospital spokeswoman said.

But when lifesavers from Ocean Beach Surf Lifesaving Club found him on Saturday, he was unconscious and the pole he had smashed into was bent at an angle.

Moments earlier, a southerly buster had lifted the man approximately 15 metres into the air and carried him away from the beach towards bushes and a nearby road, police said.

"The surfer descended rapidly and was dragged through the bushes, struck a wire fence, which he broke through, and then struck and bent a street-sign pole," police said.

The man had just set up his kite on the beach when the incident happened, said Ocean Beach SLSC president Scott Hannell.

"He hadn't been in the water, he was still setting up to go out," he said. "From what I understand, most injuries in kite surfing happen at that stage.

"[The lifesavers] were doing a patrol down on the beach and saw it unfold as it happened."

The lifesavers followed the man as he was carried away from the beach, and were the first on-hand after he smashed into the street-sign.

"The injuries were pretty horrific from what I understand - when he hit the signpost it peeled off half his face, and there was talk he may lose one of his eyes.

"It would have been one of the worst [injuries we have seen]."

Mr Hannell said the man was not known to the lifesavers, and was likely just an enthusiast.

"It's a fairly popular spot for kite surfers - when the winds up there's usually a few out there," he said.

While most kites had an in-built safety release that allowed surfers to release the kite before they were pulled away by a sudden gust of wind, there was little that could be done after a gust had taken hold, said Rob Smallgood, from the Australian Kitesurfing Association.

"Once you're 15 metres in the air it's too late to pull the safety release because you'll drop like a stone," he said.

"After that, the idea is just to slowly go from one side to another like your dropping from a parachute, but while you're up there you're going to blow in the direction of the wind.

"So if you're coming down over a car park it's about trying to avoid those obstacles and come down safely."

He said it was extremely rare for trained kite surfers to be caught by surprise and unexpectedly lifted 15 metres.

"If you're on a beach and there's a massive southerly coming through, you can usually see that as there's a line of white caps coming across the water, and you wouldn't have the kite above you."

Mr Smallgood did not know how experienced the injured kite surfer was, or what equipment he had.

But as the sport became more popular, large numbers of people were taking it on without first getting crucial lessons, he said.

Mr Smallgood said kite surfing was safe in winds of up to 25 knots, but above that it was usually only experts who ventured onto the water.

Australia's Bureau of Meteorology said it recorded winds of up to 20 knots in the Central Coast area on Saturday afternoon, as per its forecasts.

"But that's not to say there wasn't a stronger local gust that happened," a BOM spokeswoman said.

Mr Hannell confirmed there had been strong southerly gusts on the Central Coast late on Saturday afternoon.

On the safety section of the NSW Kite Boarding Association's website, kite surfer Jimmy Barnett provides a firsthand account of what happens when things go wrong.

"I was hoisted 4m in the air and 50m along half the length of the beach. I landed the unintentional jump successfully, but was immediately carried again into the hostile stone seawall and timber crash barrier. "Here I snapped all four of my forearm bones, ascended over a car and then headfirst into the side of a car on the other side of the street, breaking some feet bones in the process.

"The kite settled briefly and I remember trying the safety system release with my arms flapping uselessly like seal flippers and blood spewing out of my head, cheek and eye.

"Luckily a fellow kiter with quick wits leaped on me and fully released the kite.

"The kite disappeared over the nearby houses as I slumped to the ground racked in agony, feeling incredibly pissed off with myself and experiencing disbelief that something I thought could never happen to me, had.

"Why didn't you pull the safety system sooner, you ask. The answer is that I was unfamiliar with it; I had a new bar and the situation developed so rapidly that I was simply not quick enough."

SOURCE: Stuff