DH Deciphers | Friendly vs rogue drone: How are they differentiated and tackled?

The drone attack on the Indian Air Force (IAF) station in Jammu on June 27 has brought into focus the security threat from the skies. Prime Minister Narendra Modi recently chaired a meeting to recast India’s policy for unmanned aerial systems, promising to tighten the rules and frame response strategies to tackle rogue drones.

Here are the details:

What rules govern the use of drones in India?

The Unmanned Aerial System (UAS) Rules, 2021, notified in March this year, govern the operation of drones in India. These rules replaced the Civil Aviation Requirements (CAR) on Remotely Piloted Aircraft System (RPAS), which had regulated the space since 2018.

Also read: Storage, sale & use of drones banned in J&K's Rajouri

The drones are categorised into nano, micro, small, medium and large unmanned aircraft based on the maximum all-up weight, including its payload ranging from less than 250 grams to 150 kilograms. (All-up weight is the total weight of an aircraft with passengers, cargo and fuel.)

Can drones be purchased off the shelf for private use?

Yes. But the weight of such drones has to be less than 250 grams and the speed lower than 15 metres per second. Such drones are classified as micro drones and are not allowed to fly at an altitude of more than 60 metres.

Heavier drones require approval from the Directorate General of Civil Aviation and must also submit their flight path on the DigitalSky website for prior approval. DigitalSky is an initiative of the DGCA to manage the operations and traffic of unmanned aircraft.

All drones, including the nano ones, should be equipped with the Global Navigation Satellite System (GNSS), the Autonomous Flight Termination System or the Return To Home (RTH) option, geo-fencing capability and flight controller among others.

Are there any restrictions on flying drones?

According to the UAS Rules, a drone cannot be operated within five kilometres of international airports at Mumbai, Delhi, Chennai, Kolkata, Bengaluru and Hyderabad, and at a distance of three kilometres from the perimeter of any civil, private or defence airport.

What about rogue drones?

The National Counter Rogue Drone Guidelines, 2019, state that conventional air defence systems are "generally ineffective against drones", particularly smaller drones. The military establishment has radars designed to detect large drones used for warfare, besides aircraft and helicopters.

How do counter-drone operations work?

The guidelines suggest three broad models – full-scale, mid-segment and basic – for counter-drone operations. The full-scale model is used for protecting places of national importance such as Rashtrapati Bhavan and Parliament House, nuclear installations and major airports. It involves primary and passive detection means such as radars, radio frequency detectors and electro-optical/infrared cameras. In addition, it may use soft kill measures such as radio frequency jammers and GPS spoofers, and hard kill measures such as high-power electromagnetic weapons, lasers and drone catching nets.

Security agencies may also consider mobile systems to cater to event-based deployment. Such systems may consist of vehicle-mounted and rooftop-deployable configurations.

The mid-scale model is used for metro airports, oil refineries and power plants. The basic model is for state government secretariats, monuments of national importance and important official premises. Both these models have lower capabilities than the full-scale model.

What are the challenges in counter-drone operations?

Counter-drone systems need to be capable enough to detect and neutralise a growing variety of targets, ranging from large unmanned aircraft to low-flying micro-surveillance drones. As drone operations increase, it will be a challenge to differentiate between friendly and hostile drones.