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France's aircraft carrier located in real time by Le Monde through fitness app

lemonde.fr

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Re: France's aircraft carrier located in real time by Le Monde through fitness app

#281
post #149
post #85

Earlier quoted context omitted.

I would have thought so too but Naval Gazing has a short series [0] on why it's not as dire as one might think. An aircraft carrier's location being "secret" in this case is just one layer of the survivability onion [1] anyhow. (Caveat that as someone who takes a casual interest in this, I can't vouch for accurate this is at all.) [0] https://www.navalgazing.net/Carrier-Doom-Part-1 [1] https://www.goonhammer.com/star…

It is important to note the Naval Gazing article is specifically talking about the difficulties of actually targeting a ship for a successful kill rather than just tracking it. It's in response to the idea that satellites plus missiles would mean carriers could be instantly destroyed in a first round of hostilities with a sufficiently prepared opponent. Tracking is a lot easier to do than getting data fresh and preci…

It also seems worth considering that the article's view that "spending a lot of time searching for the carrier is a good way to get killed by defending fighters" is a distinctly pre-drone-ubiquity assumption.

Can a carrier group's point defense weapons and fighters reliably counter a swarm of hundreds of cheap drones, flying lower than cloud cover, that are programmed to look for carriers over a wide area, confirm their shape optically, paint them for missiles, and take the disconnection/destruction of any one of them as an indication of possible activity and automated retasking? It's a scary world to be a slow-moving vehicle, these days.

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#282
post #2

Is an aircraft carrier's location supposed to be secret? Pretty hard to hide from a satellite I'd imagine.

>> Pretty hard to hide from a satellite I'd imagine. Clouds. (Radar sats can see through clouds but can also be jammed.) But even on a clear day, most of the people looking to target a carrier these days (Iran/hamas etc) don't have their own satellites. But a real-time GPS position accurate to few meters? That could be tactically useful to anyone with a drone. An active fitness tracker might also give away the ship's…

Jamming is a good way to make sure everyone knows exactly where you are.

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#283

Earlier quoted context omitted.

[flagged]

I certainly hope so, but we've pretty much hung Ukraine out to dry under Trump [1], just like we did the Iranian protesters. Unlike Russia, Ukraine evidently doesn't have any kompromat on Trump or the Republican Party in general. 1: https://www.yahoo.com/news/articles/us-military-aid-ukraine-...

> I certainly hope so

Then you probably should accept that proxy wars work both ways. And well, it's not really Iran's fault that its borders has crept so close to the US military bases.

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#284
post #102

Seems we need a new digital category for Darwin Awards. This is the modern way to die of stupidity — use your fitness watch app to log your miles on an online app instead of locally — so reveal your operational location. The US had one of its secret bases in Afghanistan fully mapped for anyone to see by its residents logging their on-base runs. Now, the French aircraft carrier is pinpointed en route to a war zone. Ye…

[deleted]

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#285

Cruising speed of Charles de Gaulle is 27knots which would give the runner a pace of around 1:10mins/km depending on direction. That would really screw up your Strava stats

So I'm actually confused that in the little image of his run in the article it seems he's often making absolute progress in the opposite direction the ship is going for part of each lap. Like, was the ship going unusually slowly?

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#286
post #77

I seriously doubt there is a country on earth which lacks the capability to detect an aircraft carrier's presence in the Mediterranean sea. We are not talking about stealth vehicles.

Why make it easier for them?

I think people tend to lack imagination about how some piece of intel could be used by an adversary.

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#287

Earlier quoted context omitted.

How do these work? I would think radar would have a very difficult time seeing a ship against the backdrop of the ocean from so high above. Is the satellite bouncing radar waves off the side of the ship as the satellite is near the horizon? Even if you can detect a ship, I'm having a hard time imagining a sufficiently high radar resolution for such a wide sensor swath width at such an extreme range. Is the idea that…

Even with an extremely low resolution radar hit they are very identifiable. Most naval vessels move in groups/squadrons. Carriers basically always travel with a "carrier strike group"/CSG of a dozen other ships and destroyers often travel in "destroyer squadrons"/DESRONs. So any time you see a cluster of hits, just by the relative responses of each hit you can narrow down and guess the entire CSG/DESRON in one go and…

Granted, but how does satellite radar actually see ships at all? How do the ships not blend into the ocean (the relative difference between the distances between shipsatellite and oceansatellite is minescule)?

EDIT: the sibling comment already provided a high quality answer: https://news.ycombinator.com/item?id=47458766

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#289
post #202

Earlier quoted context omitted.

How do these work? I would think radar would have a very difficult time seeing a ship against the backdrop of the ocean from so high above. Is the satellite bouncing radar waves off the side of the ship as the satellite is near the horizon? Even if you can detect a ship, I'm having a hard time imagining a sufficiently high radar resolution for such a wide sensor swath width at such an extreme range. Is the idea that…

SAR operates in side-looking slant geometry. Consider shooting a ray at the ocean at an oblique angle from a satellite: it bounces off and scatters away from you. Hardly any of the energy scatters back towards you. Now, put a ship there. The ray bounces off the surface of the ocean and scatters up into the side of the ship, and from geometry, it's going to bounce off the ship and come straight back towards its origin…

This is cool. Thanks for the detailed follow up!

Re: France's aircraft carrier located in real time by Le Monde through fitness app

#290
post #255
post #179

Earlier quoted context omitted.

Neither SAR nor high resolution optical sensing are trivial at panopticon scale. https://www.youtube.com/watch?v=-GTpBMPjjFc is a good overview of what's up there so far, and what's coming as they really try to scale the technology. Bandwidth and processing are substantial bottlenecks with SAR; Only targeted and stationary applications have been broadly useful so far, and more focus has been put on planes than satell…

> Bandwidth and processing are substantial bottlenecks with SAR; Only targeted and stationary applications have been broadly useful so far, and more focus has been put on planes than satellites for this. I'm not sure why you assume this, this is factually incorrect. Satellite based SAR has been successfully used for civilian ship detection applications (traffic management, illegal fishing, smuggling detection, etc) f…

40 years ago the USN was working on using SAR with a elliptical kalmann filter to detect _submarine_ wakes. I assume things haven't digressed since then.
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