Comment by nine_k | Hacker News Reader

Comment by nine_k | Hacker News Reader

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Does a consumer-grade 8K camera sensor detect a 20°C difference in a few pixels? Cameras have to aggressively fight against thermal noise. Visible light is much more energetic than IR; detecting a faint IR signal with a sensor which is about as hot as the object it's looking at is hard. You need to cool the sensor down; old military aircraft even carried a tank of liquid nitrogen for that.

I mean, yes, you can take a low-noise sensor, add cooling, add a telescope lens so that you'd see the shape more readily, put a bunch of these telescopes on a rotating platform to scan the sky, etc. This is doable, but the thread started with an idea that it's doable with consumer-grade ("cheap") tech. I doubt that.

While at it, even if we assume that stealth does not exist for fast and heavy aircraft, it seems to effectively exist for slow, lighter-weight drones. Ukrainian drones, built from ultralight aircraft like Aeroprakt A-20, somehow penetrate 700 miles into Russian territory to burn refineries. With a cruise speed of 70 mph (sic), it should take them 10 hours to fly this distance. Were they detected efficiently, that would be enough time to scramble an interceptor a hundred times. Apparently this does not happen.

How many of those attacks were successful? Russia has fairly advanced radar that is quite capable of picking up a plane like that. I think the more likely explanation is that it was incorrectly deemed not a threat or a minor threat.

700 miles is far more than the standard range of the A-20 (210nm). Is it possible they launched it from well within Russia thereby making it much less likely to be considered a threat?

Possible, just like Russel's teapot.

But there has been one very well published Ukrainian attack launched from Russian soil[1].

If Ukraine had could regularly smuggle several drone aircraft's and explosives into Russia and launch them, we would be seeing a lot of other effects. Such as attacks on weapon production sites deep into Russia[2].

But yes, a lot of those attacks are probably unsuccessful. With my qualifications as armchair general, I would be surprised if more than 10% of them was successful.

[1]: https://en.wikipedia.org/wiki/Operation_Spiderweb [2]: https://en.wikipedia.org/wiki/Yelabuga_drone_factory

I also don't think they'll target the Yelabuga drone factory with a drone when they could use that drone on something relatively small but high value (like an aircraft) or combustible (like a refinery), and are waiting for their heavy cruise missles to come online for targets like factories. You can't do much damage to a factory with a drone. We've seen Ukraine target industrial sites with drones, but it's not common.

These attacks were so successful that Russia is having fuel shortages right now, and decreased its exports of oil products by about 10%. It is estimated that about 30% of Russia's refining capacity is disabled by now. (E.g. https://www.bbc.com/news/articles/czx020k4056o)

So no, these are not isolated incidents, this is a big hole in air defense, and Russia used to produce some competent air defense systems. They are just not geared towards the drones, much like Patriot air defense systems are not either.

I agree the attacks were successful, I just don't agree they were successful because of lack of detection.

You generally can't continually launch a even $1mil missiles at $100-$10k drones and expect to win. The problem is that most air defenses were designed in an age where the enemy aircraft were quite expensive so it wasn't so critical to optimize ordinance cost. That IMO is the primary challenge for all militaries now.

You don't need a missile. Any fighter jet is equipped with a cannon; a bunch of 30mm fragmentation-action ammo would dispatch the drone. You don't need a jet; any decent piston-engine trainer plane can fly 4x as fast as the drone, just mount a machine gun on it. Hell, take a civilian helicopter, shoot through the open door. You have ten hours to dispatch it, given that you have detected it.

But, since this is not being done routinely along the way, I conclude that detection fails. All reports about drones shot down mention that the drones were shot down nearby, likely by local air-defense teams near the target. These could as well detect the drone visually, or by the sound.

Ukraine solved this even cheaper than cameras. They have an enormous microphone network listening for drones and cruise missiles.

Correct, and Ukraine has been doing exactly that with using simple trainer aircraft to shoot down drones.

https://www.twz.com/air/this-is-how-ukrainian-yak-52-crews-h...

The Russian air defense radar system has been badly degraded by recent Ukrainian strikes. They have been conducting a deliberate SEAD/DEAD campaign to clear the path for strikes on strategic targets. Of course the Russian air defenses everywhere far from Moscow were probably never very effective in the first place due to the usual mix of poverty, corruption, vodka, and incompetence.

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