NavList:

   

Reply

Greg,
Clancy is a fiction writer, why do you think he is trustworthy
in such matters?

Of the methods of navigation you (or he) list, only the tethered GPS
antenna
looks like something plausible.

All the rest reminds me navigation of ancient Polynesians who used
waves, bird flight, etc:-)
Internal gyros (=inertial nav) were already discussed.
They cannot be accurate for more than several days.

It seems that a submarine must surface, or come close enough to the
surface to use a tethered GPS reciever, or a sextant in the periscope.
Perhaps this is a secret, not widely publicized, and not known to
Clancy:-)

I also have to correct some mistakes in my previous message on the
subject: just keep reading and finding more info:-)
This first Soviet ballistic missle was NOT fueled at start.
They kept it with liquid fuel and this was a major problem.
First fuel was oxigen and alcohol.
Then they decided that they cannot keep it for long time with this.
(Perhaps because Russian seamen could not be trusted with so much
alcohol nearby:-) There are stories about ground missiles, where this
was a real problem and they had to change the fuel because of that:-)

Their final choice was nitric acid + kerosene.
It is true that the missile had to be installed vertically,
but not on the deck, over the superstructure:-)
There is a photo of such launch on Internet.

Even earlier, they had a cruise missle, launched from
Whiskey Long Bean submarines. (I've seen several of these in my childhood,
and still remember them as possibly the ugliest thing afloat, ever:-)
You can find some photos on the web but they do not really tell
the truth, how ugly this monster was).
Cruise missile was first unguided, then equipped with an inertial system.
It had range 500 km and a nuclear warhead. Launched from surface.

The inertial nav system (of the ship) is absolutely necessary.
And I found what for.
The problem is that the rocket ia launched from the surface position,
you have pitch and roll, and you cannot aim the missile.
This was done as follows:
1. The gyros of the missle were started and synchronized with the
gyros of the boat. The gyros of the boat "knew" the space orientation,
as every inertial navigation system does.
2. So the missle could be launched in more or less arbitrary direction,
and AFTER that its gyros directed it in the desirable direction.
3. This helps to orient, to aim the missle after the start.
4. But this does not help to find the ship's position, unless
you did some Cell Nav shortly before.

Same applies to missiles launched from underater.
To know the position at the moment of launch, you need inertial nav
system.
Nothing else can give this position.
But shortly BEFORE that, you have to correct your inertial system.
Either by Cel Nav or by a satellite, unless you are close enough to a
friendly shore to use radio bearings. This is how I understand this
launching business now.

(Source of all this new info is the book: Zapolsky, Missiles start from
the sea, SPb, 1994, there is an English translation on the Internet).
The author took part in the first tests.
The first launch of ballistic missile occured on Sept 16, 1955.

Alex.

   

Reply