NavList:

I find it interesting this discussion about paper charts and subs with sextants.  I have been away at sea for awhile, so I hope this hasn't been covered in my absence.

 

If we are reduced to using a sextant because of the loss of other navigational methods (inertia and GPS aboard subs if my facts are straight) then we would need to use the sextant at sea.  The trouble is that we would need to plot the LOP's derived from the celestial bodies.  On what do we plot these lines? This is the crux of the matter. Now there are computer programs out there that will give a Lat and Long from a series of sights, and my Navy issued "ICE" ECDIS can take celestial LOP's as inputs, but that would assume that the only failures would be in the navigation systems and not a general electronic failure. 

 

In the case of EMP, or other catastrophic loss of electronics, that would force a sub to use HO 229, the NA and a sextant, we would be likewise forced to plot the position on some sort of paper to figure out where we were.  If all the sub had for paper charts were harbor charts, and they were still mid ocean or even outside of visual and radar range, they had better start making some plotting sheets. (possible from any sheet of paper if you need to).

 

I guess my answer to the issue is that a prudent CO would have the NA, some manual method of reduction, and a good supply of universal plotting sheets along with plotting tools in case he did have to break out the sextant.  In this case, he should be able to find his location anywhere.  Of course he'd need a compass (magnetic?) and the plant to be running to get anywhere, but that is another issue altogether.

 

Jeremy