I've seen UAVs kill birds before though, and it's always a horrifying scene, reminiscent of the plucky character in a dystopian sci-fi movie meeting the all-powerful violent crusher of doom. Moderately powerful UAVs can easily resist birds. Even an off the shelf DJI Phantom 4 can - with stock everything - go 72 km/hr horizontally. I'd bet the eagle could catch up to it, however: the problem comes when the bird meets drone.
Every bird-drone incident I've seen is usually an instant kill (or comes close) for the drone, simply because most of the surface area of the drone is covered by four spinning propellers. The tips of these blades are going several hundred miles per hour, and the area of the top not covered by blades is only a few square centimeters covered in smooth, hard to grip plastic. Now you're telling me that a huge bird (that has a wingspan longer than most humans are tall) can grab onto this tiny place without becoming mincemeat? If the blades are carbon fiber, there's a good chance they won't break upon cutting the bird in half.
I've worked with drones enough to know what will and won't stop them. A bird won't: it'll brush the blades and fall to the ground in a bloody mess. A bullet will. Bullets are tried and true technology, we know how to use them, they're not ridiculously expensive, and they will certainly take down any drone of reasonable size.
This is PR, plain and simple. There's no other explanation for it, unless France's air force is hilariously incompetent, which I would doubt.
you can see that the blades got damaged because they're cheap plastic, perfectly fine if you just want to shoot some videos from an aerial pov. if you want to use your drone offensively you'd use a) a swarm of drones, b) a significantly stronger one or c) a swarm of hardened drones.
as the parent mentioned: the rotors become brutal weapons if you make them from carbon fiber or cheaper but still durable material
Military drones like the predator weigh more than a car, and we have plenty of weapons built for that. Small off the shelf drones are not something you can really hit with a missile, but you can shoot them down fairly easily with a gun. However, you don't really want to fire up into the air in the middle of a domestic city, making birds a more interesting option.
PS: They don't need to disable the drone, simply adding 8lb of weight will take most of them down easily.
There's also no way that a golden eagle can fly away with the drone: it'll definitely be taking it down too. A golden eagle has a payload of 900 grams. [0] Nine hundred grams! Videos of birds (typically not golden eagles) 'carrying' dogs or even goats for a half-second or so are because they perform a special swooping maneuver with their wings that lets them lift things up, taking advantage of the ground effect. There is no way this would work with a UAV, unless it was moving extremely slowly near the ground.
There are lots of people defending this PR piece because it sounds cool. This happens every time a new way to 'catch drones' comes out. Yes, golden eagles are extremely majestic. The reality however is that bullets are by far the best way to take down an unwanted UAV. Please, think about the realities of this: several hard blades going hundreds of mph is something you can only stop with a bullet. It doesn't matter if you put a super-suit on your eagles - at best, you'll just make the eagles die of internal bleeding instead.
Finally, if this UAV is flying over a city, it'll be very often above roofs/rivers/canals/etc where it's safe to crash. Give some special ops 20 minutes of training on shooting UAVs and a bullet, not a bunch of raptors that'll end up dead - that's the way to protect your city.
[0] https://raptorresource.blogspot.nl/2015/11/how-much-can-bald...
Anyway, you can build mortar's for under 100$. Rockets are a flexible terms, but 10 for under 20,000 is very possible. Importantly your drone needs to carry the box and what blows up where a rocket can be the box that blows up messing with your payload calculation.
PS: "Rockets red glare" refers to a mechanically simple devices that are still useful weapons.
Shotguns with bird-shot would be effective and are comparatively low risk to bullets.
https://en.wikipedia.org/wiki/List_of_birds_by_flight_speed
As to rotors they can generally avoid them. However, this is just for off the shelf drones, you can build something that can get past them but it's a lot more effort.
In any case, they most certainly cannot 'generally' avoid rotors. I have seen birds of prey - as well as smaller birds - attack and/or collide with UAVs. I have never seen a bird escape uninjured except with a small quadcopter with plastic blades. If someone was orchestrating a terrorist attack they would obviously need some sort of payload, and would not be flying a palm-sized plastic-blade quadcopter.
I think eagles are cool and they're clearly majestic creatures. But using them to catch a set of spinning blades in the sky - when a bullet works just fine - is really stupid.
Anyway, birds learn so you can train them to avoid the blades. Shooting something near buildings is risky and loud even with buckshot. Birds can also follow terrain etc. So, while this is far from perfect it's not a terrible or useless idea.
A mass of 4 kilograms or so diving at several hundred km/h will do a lot of damage, keep in mind these birds kill adult deers. They're also used to avoiding the dangerous parts of the animals they attack and fast bird vision gives them a better view of rotors than the indistinct blur humans see. At 10000 rpm or so, birds of prey should actually be able to follow the movement of blades.
They also have more lifting power than most drones, which means they are absolutely able to wrestle them to the ground if the initial impact doesn't knock them off (especially since they will have a far better understanding of what's going on than the drone's operator).
I am as tempted as anyone to think that I am smarter than professionals I read about in the news, but I'm pretty sure these guys have thought their experiment through.