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Old 06-28-2019, 12:21 PM   #16
UglyMowgli
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< Magic points are an interesting idea. I am not sure how a boomer could know its position over sea floor terrain without using an active sensor to "look">

I know zero about real world submarine navigation and I suppose it is classified, but Inertial Navigation Systems INS have been around for decades. It was standard on the 747 and other airliners before Satellite GPS. Using sensitive gyroscopes and acceleromotors (force sensors) which calculate distances, velocities and accelerations a submarine would know its position fairly accurately without need of any external references, except some initialisation point when setting the system initially and checking its accuracy. On aircraft the initialisation point on startup is the gate which is a known coordinate. Maybe they utilise magnetic fields as well?

I expect all submarines would have back-up systems like this to cross-check with other more accurate systems. I have no-idea what a magic point is.



An INS drift after some time even the laser one, what is good for an airliner flying for few hours is not for a sub navigating under the sea for months. they need to re-calibrate their position. there is few methods
- GPS but need to have a signal (and during a war, well don't count on it)
- Old sextant method, need time and like the GPS method need to be on periscope depth - too dangerous during a war/crisis


- Using a distinctive seafloor topography (a big rock in the middle of a flat) or a shipwreck whose exact location is well known. This is the magic point. And to find it, there is few systems like a XXXXX or a XXXXX - sorry this is classified


And since nobody talk about, the title of the movie Wolf call refer to the sound of an active low frequency sonar using modulation to bypass the target distance ambiguity. This sound is like a wolf howling.
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Old 06-28-2019, 03:02 PM   #17
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Originally Posted by US IRON View Post
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< Magic points are an interesting idea. I am not sure how a boomer could know its position over sea floor terrain without using an active sensor to "look">

I know zero about real world submarine navigation and I suppose it is classified, but Inertial Navigation Systems INS have been around for decades. It was standard on the 747 and other airliners before Satellite GPS. Using sensitive gyroscopes and acceleromotors (force sensors) which calculate distances, velocities and accelerations a submarine would know its position fairly accurately without need of any external references, except some initialisation point when setting the system initially and checking its accuracy. On aircraft the initialisation point on startup is the gate which is a known coordinate. Maybe they utilise magnetic fields as well?

I expect all submarines would have back-up systems like this to cross-check with other more accurate systems. I have no-idea what a magic point is.
I have many ocean crossings with INS as a secondary navigation system and over the few hours of a jet crossing the error is quite large. Usually 1-3 miles or so for the trip over the North Atlantic. Age and condition of the system also affect this drift.

Here are some articles I found on Gravity Anomaly Aided Inertial Navigation System (GAINS), which is pretty interesting stuff.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579750/

https://www.navysbir.com/n09_1/N091-092.htm

https://pdfs.semanticscholar.org/860...57b0712f25.pdf

https://www.frontiersin.org/articles...019.00019/full
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Old 06-29-2019, 05:00 AM   #18
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But then the idea that the nuclear missiles need to be launched from a precisely known position in order to be more accurate to prevent civilian casualties is a bit silly on the face of it.

The entire premise of nuclear deterrence is retaliatory strikes against the civilian population of the opponent.
The movie does not reveal the details of French president's chosen retaliatory option, but my guess is that he had chosen a limited retaliatory strike against a military target. You will notice that when the orders to launch arrive and are plugged into the weapons console only one missile gets activated and only one vertical tube opens.

Its not entirely unrealistic. Many WW3 scenarios assume an escalating nuclear exchange, rather than full on all-missile bombardment. Starting from few tactical nukes, escalating into greater payloads and quantities.

And since the chosen target was military it would make sense to want to limit casualties. Captain's priviledge i guess.
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Old 06-29-2019, 05:20 AM   #19
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The plot is pretty silly with some huge holes but all is forgiven for the excellent job with the crew and submarine interior scenes.
Yeah, I was disappointed in the end given the apparently good production values. Weak script, shallow characters, average actors at best. The script seems to be quite inspired by Crimson Tide (plus the sound guy seems to be inspired by Jones from Red October).

By far the worst moment is when they decide to shoot down that helicopter with some recoilless launcher they shouldn't have in the first place. They actually miss it, but somehow the projectile still gets activated and damages the helicopter which instead of crashing down, explodes in mid-air for no good reason.

It's a shame as it seems like there were enough ingredients there for a much better movie.
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Old 06-30-2019, 06:45 AM   #20
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Many thanks beauregard for the links on INS.

I can see now that variable gravity is a problem. Theoretically, without that problem, I would think that there should be little limit to their accuracy.

I will definitely read up on these links.
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Old 07-11-2019, 03:21 PM   #21
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The movie isn't perfect (it ain't called Red October), but still really enjoyable overall IMO, offering a decent story centered on the sonar analyst, the iconic figure of submarine warfare who's too often ignored in movies (with the exception, once again, of Red October, but McTiernan's movie is perfect anyway, so it should go without saying).

The MN (Marine Nationale - French Navy) did contribute a lot to the production, to the point that the actors and the set managers could go inside both classes of submarines showed, the Rubis SSN and Triomphant SSBN and got a dive in the SSN. This allowed the producers to actually build a 1:1 model of the SSN command center for the scenes there (minus stuff that appeared in pictures the MN deleted from the cameras once they left the boat, of course). SSN COs were working alongside the producers, and in several scenes of the movie, numerous extras were... actual French submarine crew members playing their own roles inside their boat.

Not without weaknesses, of course, the helicopter scene being a bit, well, too much (though at least, the dialogue indicates the origin of that PzF 3, which the CO, Grandchamp, says was brought by the special forces and left on-board when they were deployed - which, BTW, is why the crew realizes only too late the RPG has a safety lock). Also a particularly annoying mistake, which has zero excuse, is the ABM intercept attempt, where the video shows... an Exocet AShM being fired from its canister. It wouldn't have cost anything more to put the proper stock video of an Aster 30 SAM being fired from the VLS of the ship (the Aster 30B1NT will have a MRBM intercept capability, which wouldn't be reliable in any way to intercept a SLBM, but it'd be believable that they'd try anyway, nothing to lose at that point). Other mistake that led to snarky comments by French viewers is during the Crimson Tide hommage scene, when each crew enters their boat, the SSN new captain does a US-style salute rather than a French one (which looks like the British, you can see it properly done in other scenes).

In terms of procedures, though, it's a really enjoyable watch, particularly on such details as the crew getting their headcaps, shrapnel glasses and gloves when shifting to battle stations (if you google pictures from the French ships and boats, you'll see that this is SOP there) as well as duct taping the old CRT screens to limit the possibility of broken glass flying around after a near miss.


Favourite quote, for me? "Dans la mort, il n'y a que la victoire qui est belle."//"In death, only victory is beautiful." from ALFOST.


For curious people, the director of the movie (it's his very first movie, BTW) wrote another one a few years ago, which is really good albeit in an entirely different context, called The French Minister. It's an autobiographical movie about his time under the French Foreign Affairs Minister in the 2002-2003 era, when he was a young top-level civil servant under a kinda eccentric Minister (de Villepin could be weird for his underlings IRL apparently), and his job was to write the speeches.

And of course, came the small thing known as the 2003 Iraq War, the movie showing you in a pretty amusing way the lead-up to the war from the French PoV, all the way until de Villepin's famous speech at the UN to oppose the war.
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Old 08-03-2019, 03:03 PM   #22
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very good movie, just watched it.
better then the hollywood crap, much better.
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Old 08-12-2019, 09:40 PM   #23
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I saw it a couple days ago, and it was pretty good. Easily the best submarine film since Hunt For Red October.

Couldn't help but be annoyed though at the inconsistent depictions of the mystery Russian sub. First they portray it as a Delta type SSBN, then in the archives it is portrayed as a Victor III SSN, then when it makes it's key move in the story, it's back to an SSBN.

For all the work they did into getting a lot of things right, it blows my mind that such a relatively simple thing got done so badly.
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Old 08-14-2019, 03:49 AM   #24
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Yep, that and a few other easily-avoided mistakes are pretty jarring compared to the attention to detail shown in the rest of the movie.
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