New figures show pilots at Australian airports have spotted hundreds of drones in restricted airspace in the past two-and-a-half years, but experts say Australian law complicates the use of technology that could defeat a rogue drone attack.

Key points: More than 220 drones were spotted at Sydney Airport in the past 30 months

More than 220 drones were spotted at Sydney Airport in the past 30 months It may just be the tip of the iceberg as authorities are only now rolling out technology to measure the number of incursions

It may just be the tip of the iceberg as authorities are only now rolling out technology to measure the number of incursions Experts say Australian law restricting the use of drone-killing technology needs to change to prevent an aviation catastrophe

Data from Airservices Australia, which oversees flight navigation and air traffic control, shows Sydney Airport recorded 222 drone sightings in the past 30 months, almost half of all sightings around the country.

There were a total of 468 sightings by pilots across the country — most of these at airports.

Late last year suspected drone sightings saw flights at Gatwick Airport — England's second-largest air transport hub — grind to a halt.

Experts say if a drone hits an aircraft's windscreen or wing, the result could be "catastrophic".

Recent research from the University of Dayton Research Institute shows "large aircraft won't always win in a collision with small drones".

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However one of the world's largest drone manufacturers, DJI, said the institute's findings and video were misleading as the test speeds were far higher than what occurred in the real world.

Australia cracks down on drones

Australia's Civil Aviation Safety Authority (CASA) said it would roll out drone-tracking technology at major metropolitan airports over the next few months, to try to get an accurate picture of the scale of Australia's problem.

CASA spokesman Peter Gibson said the equipment would be used in future for enforcement purposes.

"We can identify where drones are, where the controller is, often get the serial number of the drone, and that will allow us to then pinpoint people who are breaking the rules and issue the appropriate penalties," Mr Gibson said.

"Fines can be in excess of $10,000. If a matter goes to court, a court can impose a jail sentence of up to five years."

Drone operators will also have to register the serial number of their device with authorities, starting from the middle of this year.

CASA has signed a contract with Counter Drone Solutions, run by former policeman John Hildebrand, to supply the equipment.

"With the data we're seeing around airports and prisons and stadiums, drones are everywhere," Mr Hildebrand said.

"The risk is one of those drones could fly into an aircraft engine, the aircraft windscreen, or some other componentry of a helicopter that could cause an aviation incident."

John Hildebrand runs Counter Drone Solutions. ( ABC News: Jennifer Huxley )

He will use fixed and mobile devices that include radio frequency sensors that listen for the drone's command signal, and identify the pilot's location.

Authorities can use multiple frequency sensors to triangulate location, speed, track and distance of the drone.

Other technologies, like radar and high-quality optics, can also be deployed.

Australia 'hamstrung' by privacy, telecommunication laws

But some experts say Australia needs more aggressive drone-killing technology — such as radio frequency jamming and "protocol manipulation", also known as "spoofing" to seize control of drones that enter restricted airspace.

Spoofing cracks into the communication protocols of the drone and sends it to a location predetermined to land, and the UK military was reported to have used it at Gatwick.

Counter-drone equipment deployed on a rooftop at Gatwick airport. ( AP: John Stillwell )

"We need the technology in the airports, but the legislation in place prevents the use of detection equipment, and specifically defeat technology," Mr Hildebrand said.

"So we might have a rogue drone operator operating at say, Sydney Airport, and we want to take it out, but the legislation hamstrings people, to do their job."

Aviation legal expert Ron Bartsch said the current legislation was not designed with drones in mind.

"Part of the difficulty is not so much the technology that is available out there, it's how much it can be used," Professor Bartsch said.

"One of the restrictions in Australia and elsewhere is our telecommunications laws which prohibit certain types of scanners and people interfering with telecommunication.

"Until and unless we modify some of our telecommunications legislation, we're not going to achieve the benefits … (and) advantages that we can gain from this counter-drone technology."

Professor Bartsch said the "drone epidemic" needed industry and government working together to prevent disaster.

"Obviously if [a drone] were to hit a windscreen of an aircraft, or be ingested in the engine of a jet aircraft, that could have potentially catastrophic effects.

"It's still very much a work in progress, and let's hope something can be done prior to an accident happening."