'It's deadly serious': Video shows the terrifying moment a drone almost takes down a helicopter

Video has captured the moment a drone came within just three metres of a helicopter carrying five passengers.

The video shows a white dot appear above the horizen as the helicopter flies towards Coogee and within two seconds, passes underneath the aircraft.

The drone came within metres of a potentially catastrophic collision.

The drone came dangerously close to the helicopter. Photo: 7 News
The drone came dangerously close to the helicopter. Photo: 7 News

Stephen Leahy Westpac Life Saver Rescue Helictopters told 7 News "There is very little doubt indeed that that aircraft would've been brought out of the sky".

The video was captured on Saturday morning.

A pilot was flying 152 metres above sea level in restricted airspace called the 'Bondi five helicopter lane' with five passengers on board.

He estimates the drone was just three metres away from his aircraftwhen it passed by.

The pilot believes the drone came within just three metres of the helicopter. Photo: 7 News
The pilot believes the drone came within just three metres of the helicopter. Photo: 7 News

Aviation Editor Geoffrey Thomas said "it's deadly serious".

"They are going to cause an absolute tragedy - there's no question about it," he said.

The pilot posted the video online to warn it's only a matter of time before a collision takes place and to urge drone operators to learn the rules imposed by the Civil Aviation Safety Authority.

The drone was captured on video. Photo: 7 News
The drone was captured on video. Photo: 7 News

Peter Gibson from Civil Aviation Safety Authority said "it's a big wake up call to anybody flying drones".

"It's their responsibility to follow the safety rules at all times."

It's not illegal to fly a drone along the area in question as long as it doesn't come within thirty metres of people and stays below a certain altitude.

Drone users are being urged to follow the user guidelines. Photo: 7 News
Drone users are being urged to follow the user guidelines. Photo: 7 News

Aviation experts believe recreational users should be forced to get licenses too.

Fines for breaching the rules range from $900 to $9000.

"The fines should be increased and we should also be talking about jail time as well," Mr Thomas said.