[PSUBS-MAILIST] Snow White navigation (was: Snow White virus)

["Michael B. Holt" <mholt@richmond.edu>]

"Sean T. Stevenson" wrote:
> 
> How much room do you have in your sub?  As far as DR is concerned,
> I like to lay out a chart and use a pencil...  

Somehow, plotting a course with a chart and pencil always looks
more accurate, doesn't it?

> Assuming you have
> an electronic solution in mind, are you talking about a GPS unit
> or some sort of ECS?  Electronically I can see using a fluxgate
> compass and external knotmeter to provide NMEA info on course and
> speed, with the GPS overriding when the signal becomes
> available (when you are surfaced).

As I said, I supsect this sort of thing is available.  Probably
in a high-end GPS unit, come to think of it.  This is just
a thought-experiment.

> Adjustment for current would need to be made according to a
> tide/current atlas, but the information in these publications
> is generally surface oriented. 

Come to think of it, is there any charting done with submarines
in mind? 

> How much of a discrepancy will there be at depth?  

Good question.  Possibly none.

> As for staying out of  the way of traffic - you're in a
> submarine... just who are you expecting to run into?

I'm more worried about fishing boats and the like on their way
to wherever they are going.  They'll stay in certain lanes,
if only out of habit.

This does get back to the question of "What do you expect
to do with your submarine?"  Submarine use can probably be
divided into a very few specific categories, based mostly
on the range and endurance of the boat.  How many of us
expect to wander any distance?  Will there be a repeat of
Simon Lake's 1898 trip that covered 1000 miles, part of it
in the Atlantic Ocean?  I doubt it.  Most of these boats
will drop to the bottom, cruise for a short distance and
get back to the support site rather quickly.



Mike