[R-390] OT: Submarine navigation

[GRANT YOUNGMAN]

WW2 boats were essentially surface craft that could submerge.  Celestial navigation was the primary method of position determination.  With the advent of nuclear power (and even some of the diesel electric subs) in the late 50’s, and the teardrop hull design, boats became true submersibles — built to run submerged.

The SINS — Ship’s Inertial Navigation System was pretty sophisticated for it’s time.  It worked well, although I do recall at least one time that it put us (this was the early 70’s) in the middle of mainland China.   And the gyros were problematic, very expensive, and failed frequently enough that they were a critical supply item.   It’s also possible to take a star sight with a periscope.  We carried LORAN (as I recall it was LORAN-C) as well, but I don’t recall it ever being used.

On a trip to the Arctic in 1970 we had one of the first satellite navigation systems on board.  (No GPS in those days, and the SINS did not work well at extremely high latitudes, at least for position).  We had to come to periscope depth at about the right time, stick a mast out of the water, and then it would take about 20 minutes to get a satellite pass and fix.  Running under the ice, you had SINS and dead reckoning.  Never got lost :)

Even in the 60’s and 70’s — (not really the dark ages) — subs did not have to surface.  In a typical 8-12 week patrol you'd surface once — in the middle of a moonless night, for as little time as possible — to clean the periscope head windows.  A modern (includes 60’s 70’s) boat is completely self sufficient (makes water, makes oxygen, cleans the internal atmosphere) and can remain at sea and submerged indefinitely — except for the limit of about 120+ days driven by food supply.

Grant NQ5T


On Sep 9, 2014, at 8:35 AM, Ben <brloper at gmail.com> wrote:

> If you're talking 60-70's time frame then a pretty advanced INS .  WW2 they only stayed under water for a few hours and then in an attack.
> 
> Sent from my iPhone
> 
>> On Sep 9, 2014, at 7:40 AM, Blair Batty <blairbatty at gmail.com> wrote:
>> 
 ...
>> I suppose today they have all sorts of magic, electronic gps devices, so
>> they can travel for months without every surfacing. But what was available,
>> say in the 60's-70's?
>>