Passenger Rescued As Plane Dives Into Ocean

A man travelling in a light aircraft has been pulled to safety after his plane nosedived into the sea off Sydney.

Onlookers on the beach in the northern part of the city plunged into the choppy ocean to rescue him.

An eyewitness told reporters he was working on a nearby building site when he noticed the plane circle overhead before pitching into the ocean.

"Me and another guy ... we ran out, swam out, we pulled one guy out, the passenger," he said.

"We got to the aircraft but (the passenger) had already popped out, he was sort of floating. He couldn't swim, he'd hurt his back pretty bad so we paddled him over to the shore."

The man was stabilised on the rocks before being winched into a rescue helicopter and taken to hospital with spinal injuries.

The aircraft sent a mayday alert before coming down in strong winds around 165ft (50 metres) off Curl Curl beach.

Superintendent Doreen Cruickshank said the aircraft appeared to get into difficulty as it was flying north across the beach.

"It nosedived into the water, it stayed on the surface for about two minutes and then sank," she said.

The pilot died in the crash despite two policemen swimming to the wreckage to try to find him.