Bird Vs Drone Vs Bird

Conflicts between birds and drones go way back. One on side, birds of prey in particular have targeted small drones for as long as they have been flying, and many drone operators have stories about bird attacks. Some of these have gone viral on social media, like the drone which was grabbed out of the air before being carried away and dumped on a mountainside at an altitude of 10,000 feet.

In the early days of counter-drone protection, some police forces tried using trained birds to tackle drones. The most celebrated was project in the Netherlands in 2016, but the French military and others also tries trained eagles. However, the Dutch project was dropped after a year for being ineffective as well as hazardous to the birds, and others similarly failed to take off.

While birds are vastly more agile and better adapted to aerial combat, they are likely to get injured when encountering anything with rotor blades. For example, in Ukraine a wild kestrel, later named “Shriek,” broke a wing downing a Russian drone. A Ukrainian drone crew saw the encounter and rescued Shriek, who ended up being treated at the Kolibri Veterinary Clinic.

We are now more likely to see the opposite happening: drones attacking birds. This is because a large bird looks similar to a drone on radar, so there is a risk an interceptor drone will be sent to down it.

The wingspan of white stork can be over ten feet, bigger than a Shahed drone. Like drones, the birds may fly at a height of several hundred feet and, like drones, they are non-metallic and have relatively small radar signatures. While storks have a much lower air speed, perhaps 30 mph compared to over 100 mph for a Shahed, their ground speed may be similar.

Most air defense radars tend to filter out small, slow objects as likely to be birds. It is only relatively sophisticated radars, like EchoDyne’s EchoShield, which can pick out the ‘micro-doppler’ signature of a spinning rotor blade and definitely tell whether a track is bird or drone.

Without more advanced sensors, mistakes happen. There is at least one incident on video, where a Russian FPV interceptor closes in on two large birds and hits one. Although initially wrongly identified as storks, the birds were Dalmatian Pelicans a globally threatened species. Even though the target in this case was clearly a bird not a drone, the Russians not only killed it but put the killing on social media. But in the case of the stork, the bird saw the drone and outmaneuvered it.

Flying Like A Bird

The ease with which the stork evades the drone shows how well evolved birds are compared to drones. Birds can change the shape of their wings almost instantaneously, spreading out to create drag and lift and perform sudden turns or hover above prey like a kestrel, or folding up so the peregrine falcon can stoop on prey at 240 mph.

Researchers have long sought to imitate these capabilities. There is a whole class of flying machine known as Ornithopters with flapping wings, most of which have been notably unsuccessful. The few exceptions include AeroVironment’s 2011 Nano Hummingbird drone, but even this only had endurance of 11 minutes.

Perhaps the most promising area for research is in morphing wing structures which imitate bird wings in changing shape for more stable, resilient and energy-efficient flight. Such work is still very much as the demonstration and proof-of-principle stage.

As well as agility, birds have an edge in flight endurance. A white stork may only fly 400 miles between stops, but the bar-tailed godwit, pigeon-sized wader, can migrate over 6,000 miles without stopping for food, water or rest.

Birds like storks are nature’s experts at using air currents to get a free ride. They typically take advantage of thermal updraughts to ascend to high altitude effortlessly, while pelicans exploit the lift generated by wind blowing over waves. Albatrosses use an advanced technique known as dynamic soaring to fly long distances without flapping their wings, simply by exploiting the difference in wind speed at different levels. Drone developers are exploring this technique which may one day enable drones to travel trans-oceanic distances without using fuel, but there is a lot of catching up to do.

Birds are also ahead in co-ordination. Harris Hawks hunt cooperatively in family groups of four to six birds, using a variety of tactics. Most common is a simultaneous attack with multiple hawks diving in from different directions, so a rabbit dodging one hawk runs straight into another. In “relay attacks,” hawks swoop down one after the other, each chasing the prey for a short distance until it is exhausted and can be taken easily. These relays can involve twenty different chases. A third technique is used to flush out prey which takes cover in vegetation. All are efficiently coordinated without radio communication or central control.

Perching on branches, power lines and other structures is another avian talent which researchers are still attempting to duplicate, often with direct copies of bird feet.

At present various drones are camouflaged as birds, but bio-inspired drone designs are still in their infancy. For the meantime, drones cannot match birds in agility, endurance, co-ordination or perching.

Ukraine’s iconic white stork wins a victory over a Russian drone. But the natural skills which birds have possessed for millions of years give an idea of what future drones will be able to do.