Drone vs drone in Ukraine

Let's break down this drone vs drone strike reportedly over the skies of Ukraine.

https://twitter.com/nexta_tv/status/1580518271635566592

As of this writing, the camera drone is claimed to be Ukrainian, and the victim drone is claimed to be Russian. Though true to form, Russian social media is claiming the other way. Let's break down what happened.

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TL;DR

A drone comes up behind another drone and moves above and then drops down, destroying a propeller on the victim drone, and probably downing the victim.

The drones

The victim drone appears to be a DJI Mavic 3. This is a quad-copter weighing 895g (31.6oz). This is a common commercially available drone worth about $3,000 USD.

We don't know what type of drone the camera drone is. The Ukrainians fly a number of drones, from smaller commercial drones to large lifter-style drones. The camera drone could be a lifter-style drone trying to catch the victim in the landing gear, a grenade-dropping drone catching the victim in its release mechanism or another small drone that just YOLO'd and hoped. I have heard one commentator say the camera drone is also DJI, but I have no evidence of this.

Which drone is moving?

From the video, it appears that the camera drone might be stationary and the victim drone is the one moving. But, looks can be deceiving. At that altitude, a drone needs to be moving fairly fast before noticing any movement along the ground, and most drone cameras have pretty good horizon-locking stabilisation. If the victim drone was moving and the camera drone was still, then the victim drone would be tilting side to side (roll) or back to front (pitch). So, it looks like the victim drone is hovering though it might be going straight up or down too.

The blind spot

The camera drone comes from behind the victim drone. The Mavic 3 is a dead cat format quad, meaning that the rear arms are at more of an X while the front two arms are at a flatter angle. This keeps the front propellers out of the camera with a minimal sacrifice in performance that only matters to free-style and racing pilots. From a distance, the dead-cat format of the victim drone is visible, so the camera drone can easily approach from behind. As the camera drone closes the distance, the rear battery light is visible, the sensor cowling at the front is visible, and the folding arms show that the nearest arms fold lower than the further arms. On most folding quads (and on the Mavic 3), the front arms are higher than the rear arms - again to keep the propellers away from the cameras and minimise the amount of debris the propellers throw into the cameras and sensors.

Collison avoidance

The DJI Mavic 3 does have collision avoidance sensors and I have no way of knowing if these were active. Yes, there are backwards and upwards-facing sensors. However, these sensors might not be able to react fast enough to the camera drone.

Swing, miss, swing again and hit

The camera drone attempts to move above the victim drone and pounce downwards but misses on the first attempt. The camera drone misses but is still behind the victim, so it's unlikely that the victim knows what is about to happen.
The camera drone repositions above the victim and then punches down.
We see the camera drone holds steady, and the victim drone cartwheels off to the right while propeller debris fly in front of the camera.
It appears that the victim was struck on one of the rear arms, probably the right rear arm. The victim rolling right could be from the unequal downwards strike or the sudden unequal thrust force from the loss of the right rear prop.

Catastrophic damage

Typically, a quadcopter can survive minor damage to the props, but severe damage will make the quad unflyable, and it will fall from the sky. From the amount of debris we see, and because the camera drone continues to fly seemingly without problem, it's likely that the victim drone fell out of the sky. The impact on the ground would damage the drone further.

Capture with a net

One commenter on twitter suggested deploying a net would allow the camera drone to bag the victim and repurpose it. That's a cool idea with some risks that might not be worth it.
First of all, at present drone on drone fights are uncommon and it's probably better for a drone to carry more optics, battery or a grenade than a net.
Second, a DJI Mavic 3 is 900g and the hunting drone would need to have that much spare lifting capacity.
Third, a captured drone is likely still transmitting telemetry to its operators, and so they might be able to gather intel to order a strike on the hunter drone's operators.
Fourth, a drone caught in a net is likely to damage props, motors and possibly electronic speed control circuitry. I learnt this the hard way when my cinewhoop sucked up a net curtain - but any sudden stop the spinning propellers can be bad. That damage is repairable, but it's still damage.

Double drone-bros, what does this mean?

Small drones are likely to feature more in future wars and anti-drone technology will undergo innovation. One possible anti-drone measure would be to use specialist drone-killer drones, probably powered by AI. A killer drone has the advantage that it can take down several targets in quick succession with a lower risk of collateral damage.

I hope you have found this article informative. I have been flying drones for a little over six months and am not an expert by any means, so any errors are my own. Have at me in the comments.