NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Dip-meter again
From: Lu Abel
Date: 2012 Apr 11, 15:39 -0700
From: Lu Abel
Date: 2012 Apr 11, 15:39 -0700
I correct myself: While the warhead's final path is strictly ballistic, INS guidance is used for much of the missile's trajectory. This is especially important with multiple warhead missiles, where each warhead must be sent on an independent ballistic path. By the time a warhead re-enters the atmosphere, it's on a ballistic trajectory. But it can certainly be under INS guidance for more than half of its flight.
From: Lu Abel <luabel@ymail.com>
To: "NavList@fer3.com" <NavList@fer3.com>
Sent: Wednesday, April 11, 2012 2:15 PM
Subject: [NavList] Re: Dip-meter again
Let's be clear here.The "B" in ICBM stands for ballistic -- following a preselected ballistic path like an artillery shell, not under active guidance. From a weaponry standpoint, you can't jam or interfere with something that's strictly on a ballistic trajectory.BUT .. when a missile is fired from a silo or other launch facility, it has to get into the correct ballistic trajectory. That's where an INS came into play. INS served as a guidance-just-after-launch capability, not as guidance throughout the missile's flight.
From: Alexandre E Eremenko <eremenko@math.purdue.edu>
To: NavList@fer3.com
Sent: Tuesday, April 10, 2012 1:25 PM
Subject: [NavList] Re: Dip-meter again
Gary,
Sorry, I don't understand the meaning of your "No" :-)
Inertial system was also developed for submarine.
But what I was discussing was the MISSLE GUIDANCE SYSTEM.
Which according to Wikipedia was inertial.
The submarine could use any navigation system, and I suppose
inertial one was less accurate than Cel Nav.
And that Transit was developed with the explicit purpose
(or one of the purposes) to improve the missle submarine navigation.
Again, I learn this from the Wikipedia article).
So apparently inertial nav for a submarine, was not sufficient.
Alex.
On Tue, 10 Apr 2012, Gary LaPook wrote:
>
> No, the INS was for the submarine and came in, I believe, in the late '50s, for some reason 1957 sticks in my head.
>
> Also there were other electronic systems that provided accurate navigation. LORAN-A, since WW2, LORAN-C in the '70s, and OMEGA.
>
> gl
>
> --- On Tue, 4/10/12, Alexandre E Eremenko <eremenko---purdue.edu> wrote:
>
> From: Alexandre E Eremenko <eremenko---purdue.edu>
> Subject: [NavList] Re: Dip-meter again
> To: NavList@fer3.com
> Date: Tuesday, April 10, 2012, 11:52 AM
>
>
> Fred,
>
> I suppose that when speaking of "inertial nav" as a guidance system,
> they mean the nav of the missile itself, not of the submarine.
>
> To use an inertiale nav in the missle one needs the position
> of the starting point. This is what Sat nav was for.
>
> Now we see Shufeldt's report in new light:-)
> The reaseach was made in 1957-1961 :-)
> And then classified.
> Exactly at the time when they developed the Polaris A-1 missile...
>
> When Transit became available, they declassified the Shufeldt report.
>
> So now we know what "Precision Cel nav" was really for:-)
>
> Alex.
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> : http://fer3.com/arc/m2.aspx?i=118913
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