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

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

#261

Post by IncreasePosts »

baq wrote: post #211
garyfirestorm wrote: post #208

Earlier quoted context omitted.

We couldn’t find a commercial jet (MH370). Both, while it was still flying in the air and after it was presumably lost in the ocean. They couldn’t track it in the air nor can they still find its remains after looking for it for so long. This problem is not trivial.

There's a nonzero chance military intelligence agencies of multiple countries know exactly where that plane fell, but none can say anything, because that would reveal the true extent of their capabilities.

They could just feed the data to some associated outside party with some other plausible explanation. But, there are only a few, maybe two countries, with the ability and desire to have listening stations all over the ocean, and neither one is particularly interested in the Indian ocean.

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

#262

Post by marricks »

TeMPOraL wrote: post #258
loeg wrote: post #212

Earlier quoted context omitted.

The Indian Ocean is both larger and has significantly less traffic than the Mediterranean. And a 777 is about 16x faster than a carrier.

> And a 777 is about 16x faster than a carrier. Surely that's missing a 0 or are carriers really that fast?

Aircraft carrier speed... 33 knots or about 35mph[1]

Boeing 777 speed 554mph[2]

So about 16x!

[1] http://www.navweaps.com/index_tech/tech-028.php

[2] https://en.wikipedia.org/wiki/Boeing_777

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

#263

Post by wat10000 »

garyfirestorm wrote: post #208
elif wrote: 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.

We couldn’t find a commercial jet (MH370). Both, while it was still flying in the air and after it was presumably lost in the ocean. They couldn’t track it in the air nor can they still find its remains after looking for it for so long. This problem is not trivial.

Nobody was looking for MH370 while it was in the air. After a few hours, it rapidly became a submarine, which is a type of craft that's well known for being hard to find. In addition to that, it took on its new submersible form in one of the most remote areas of the ocean, rather than in a small and very busy sea.

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

#264

Post by jmalicki »

TeMPOraL wrote: post #258
loeg wrote: post #212

Earlier quoted context omitted.

The Indian Ocean is both larger and has significantly less traffic than the Mediterranean. And a 777 is about 16x faster than a carrier.

> And a 777 is about 16x faster than a carrier. Surely that's missing a 0 or are carriers really that fast?

Commercial airliners are sub mach1. The Charles de Gaulle is reported to go at least 27 knots at top speed.

27*16=432, a 777 goes 510-520 knots.

So maybe more like 18-19x.

For the carriers it is at least as the true top speed is classified.

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

#265

Post by [deleted] »

TeMPOraL wrote: post #258
loeg wrote: post #212

Earlier quoted context omitted.

The Indian Ocean is both larger and has significantly less traffic than the Mediterranean. And a 777 is about 16x faster than a carrier.

> And a 777 is about 16x faster than a carrier. Surely that's missing a 0 or are carriers really that fast?

[deleted]

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

#266

Post by contingencies »

literalAardvark wrote: post #248
garyfirestorm wrote: post #208

Earlier quoted context omitted.

We couldn’t find a commercial jet (MH370). Both, while it was still flying in the air and after it was presumably lost in the ocean. They couldn’t track it in the air nor can they still find its remains after looking for it for so long. This problem is not trivial.

MH370 crashed in the Pacific. Look at the globe some day from that angle and compare it to the Mediterranean.

Err, no. The consensus and available evidence including washed up components seems to be that it crashed in the Indian Ocean, that's the (also vast) space between ~Australia and ~Africa, bounded in the north by Indonesia, the Indian subcontinent, and Arabia. It crashed somewhere in the eastern portion, not far from Indonesia and Australia. Currents then took parts as far as the Maldives/Sri Lanka, IIRC. The Pacific is the other (eastern) side of Australia, which stretches from the Aussie-Kiwi approach to the South Pole to Alaska, and Vladivostok to Tierra del Fuego.

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

#267

Post by ray__ »

marricks wrote: post #262
TeMPOraL wrote: post #258

Earlier quoted context omitted.

> And a 777 is about 16x faster than a carrier. Surely that's missing a 0 or are carriers really that fast?

Aircraft carrier speed... 33 knots or about 35mph[1] Boeing 777 speed 554mph[2] So about 16x! [1] http://www.navweaps.com/index_tech/tech-028.php [2] https://en.wikipedia.org/wiki/Boeing_777

Honestly pretty crazy, although that must be the max speed. The carrier was going about 10 mph in this case (per Strava).

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

#268

Post by Phemist »

bigyabai wrote: post #209
maxerickson wrote: post #178

Earlier quoted context omitted.

So you task the satellite to where you know the ship is?

To get a naval fix, you usually define an "area of uncertainty" around the last confirmed location of the ship. The area is usually a circle with the radius being the maximum distance the ship/group could travel at full speed. So, you don't exactly "know" where the ship is, but you can draw a hypothetical geofence around where it's likely to be, and scan that area.

So the satellite can know where the ship is, because it knows where it isn't? Then it's a simple matter of subtracting the isn't from the is, or the is from the isn't (whichever is greater)?

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

#269

Post by drivebyhooting »

cbsks wrote: post #128
deepsun wrote: post #89

Earlier quoted context omitted.

Mediterranean maybe (although I'm not sure), but it's actually very hard to find a ship, even as large as an aircraft carrier, in the ocean. The empty space is just too big. Satellites have hard time taking pictures of every square mile of a sea to find any ship, yet alone the one you need.

I really don’t want to work for the defense industry, but I have to admit that they do have very fun problems to solve. You know there are people at NRO who are dedicated to ship tracking via satellite. I assume they can easily track ships without cloud cover, but how do they do it when it’s cloudy? Heat signatures? Synthetic Aperture Radar? Wake detection?

I wish defense paid better. The problems are infinitely more interesting than ads. And it’s not like social media is a saint anyway.

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

#270

Post by awesome_dude »

rtkwe wrote: post #226
signatoremo wrote: post #193

Earlier quoted context omitted.

It was sunk there because it attended an on-off event in India before that. Iran's ships don't get on regular trips far from home.

They don't but it shows they could.

I mean, a personal yacht can sail around the world, that's not really demonstrating whether the vessel is useful in combat operations anywhere in the world.
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