Courtney Thomas wrote:
Jeff wrote:

Gary wrote:

otnmbrd wrote:

That same bolt of lightening will take out your calculator so you
then have to work stars long hand. It'll also kill your digital
watch and radio so you won't have the correct time. It'll probably
short out your boat so you won't be able to work the stars out
until light the next morning. The lightening excuse to learn astro
is BS. Learn it because you want to or take a couple extra
handheld GPS. Practice dead reckoning. Know where you are all the
time.

Gaz





Let's see...... calculator gone, long hand star calc's....add a
minute or two to the solution.
digital watch killed..... in that case I'm probably dead too so
what do I care.... always have a mechanical clock that you know the
error...no big deal, was done for years.
lights out?....lite a candle or wait till daylight.... what the
hell, it's offshore navigation, what's the rush....



And how did you check the error on that deck watch? Radio? What was
the error and how much does it change daily? Can't just do the time
check anymore. Damn lightening.



With all due respect Gary, I think you need a refresher course on
celestial. I wear a "windup" watch, and have two windup ship's
clocks. All of them are accurate to a minute a month, and have a
pretty consistent error rate. I generally set them once a week, so the
error is well under a minute. So, would you care to tell us what the
expected error would be for both Latitude and Longitude?

To be honest, I don't really buy the lightning argument either. But
I'm not sure some find fault in celestial because it is not accurate
to 3 meters.


Jeff,

I'd be very interested in your opinion of where to get an inexpensive
but reliable "windup" clock/watch ?


Did I say inexpensive? My watch is an older Rolex, and the clocks are
both Chelsea. The most accurate of the three is a WWII deck clock I got
for about $250. My point is not that windup watches/clocks are perfect
backups for their more modern counterparts, but that in a pinch
electronics are not necessary for navigation. Latitude can be
determined without time, and longitude can be determined within 30 miles
even with a few minutes error. Not great for long passages, but good
enough to get you home.

BTW, my father-in-law spent 17 days in a lifeboat at the end of WWII.
He was able to navigate about 1000 miles using a Movado watch.