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THINK ABOUT IT - pabrides - 02-07-2021
If I disoriented you beyond doubt, so that you didnt know your location on earth, and if I dropped you in some ocean;
1... could you determine your approximate location, say within a few hundred miles, given a raft full of non-electronic navigation equipment and publications?
2... If yes, how would you go about it?
RE: THINK ABOUT IT - craigsl - 02-09-2021
Pabrides,
That's a great question!
Well, hopefully you'd allow a chronometer (non-battery) set to GMT and let me know the date (based on Greenwich). Without knowing the time and date I certainly couldn't get longitude and latitude would be slightly inaccurate.
The first thing I'd do is determine latitude using either the Sun, stars, or the Moon and check them again several times to insure accuracy. I'd be using The Nautical Almanac, Pub. No. 249 volume 1 (for stars) and Pub. No. 249 Vol. 2 & 3 for the Sun or other bodies.
Once latitude has been determined I'd try for longitude. Since I don't know where I am on the earth, except latitude, the intercepts based on AP longitude (whole degree) will be huge (probably) until after many tries when the calculations bring me within 60 nm or so. At that point a fix would've been obtained.
Lastly, I'd write my "Last Will and Testament" and put it into a watertight container then hope and pray I get rescued.
How does that sound?
Craig
RE: THINK ABOUT IT - pabrides - 02-09-2021
Good one Craig...
I suppose id have to include the chronometer because I said a boat load of nav stuff. However you wouldnt know the day or if the watch was accurate.
Nav texts would help though. What about finding out which hemisphere your in first. Perhaps the stars are a first good step. What do you think? Could you narrow down what month you're in... etc?
Cheers
RE: THINK ABOUT IT - Rumata - 02-09-2021
Alain Bombard did it in reality. And without bottled freshwater and food crossed Atlantic.
RE: THINK ABOUT IT - pabrides - 02-10-2021
@Rumata
Whats the story on that Bombard crossing?
BTW... why do the reply and quote buttons not work?
Cheers
RE: THINK ABOUT IT - Rumata - 02-10-2021
He was A French NAvy doctor. Young. He analyzed alot of shipwrecking stories and came to the conclusion that people on open seas died mainly of fear. Not of lack of water and provisions. He decided to prove his point. In 1952 he took 4 meter rubber boat, called Heretic, and took with him just emergency supply of food to which he did not touch. He cross Atlantic in 65 days. Lost 25 kg. Not pounds. Ate plankton and squeeze flying fish to get water. He found out that fish consists of almost 80% water. And was not salt water. Also, he taught himself to drink ocean water ina very small portions not to block his kidney. He almost died from terrible storms, for 3 days bailed out water from his leaking ship, suffered from dehydration . Most difficult problem he had experienced when he met passenger transatlantic steamer. All the world knew about his joourney. And he was invited to step on board of the steamer. He was greeted as ahero ( about half of way through the ocean) and everything went pretty smoothly until he did not smell fresh baked bread. It was too much even for this strong will man. He ate just a piece of it. This was too much for his stomach used for days of diet of squeezed fish juice and plankton. The pain was absolutely terrible. And to help it-a stron storm was coming. He needed to manage his boat, its sail, bailed ot, etc. He was 99% dead. But he made it. He proved the point. You can survive, not luxury living, but survive without almost anything. Fascinating life. He supposed to sail with another guy, Palmer by last name. But in the day of departure Palmer did not show and that's it. And by the way, Alain started his journey day his daughter was born.
For navigation, Bombard, who was an ace celestial navigator, took only his sextant.
RE: THINK ABOUT IT - pabrides - 02-10-2021
@Rumata... if I was his wife I'd be pretty pissed off.
RE: THINK ABOUT IT - Rumata - 02-10-2021
If men would listen to their wives -nobody would ever cross any pond. There is always something to fix in a barn, or leaking toilet. Or wedding anniversary. World history show this point every time..
RE: THINK ABOUT IT - Lipr - 02-10-2021
That's a very interesting story! Died of fear? That combined with confusion surely would decide the result.
Larry
RE: THINK ABOUT IT - craigsl - 02-12-2021
(02-10-2021, 03:52 AM)pabrides Wrote: @Rumata
Whats the story on that Bombard crossing?
BTW... why do the reply and quote buttons not work?
Cheers
padbrides,
Looks like the reply button's working- it'll include quotes for you.
Craig
RE: THINK ABOUT IT - pabrides - 02-12-2021
(02-12-2021, 02:25 AM)craigsl Wrote:hi craig(02-10-2021, 03:52 AM)pabrides Wrote: @Rumata
Whats the story on that Bombard crossing?
BTW... why do the reply and quote buttons not work?
Cheers
padbrides,
Looks like the reply button's working- it'll include quotes for you.
Craig
Looks like someone fixed it, but all my attachments disappeared... I'm trying to put them up again.
You can look back through the threads and see the reply or quote buttons haven't been used for a while.. what did you do? :)
Cheers
RE: THINK ABOUT IT - craigsl - 02-12-2021
(02-12-2021, 06:55 AM)pabrides Wrote:(02-12-2021, 02:25 AM)craigsl Wrote:hi craig(02-10-2021, 03:52 AM)pabrides Wrote: @Rumata
Whats the story on that Bombard crossing?
BTW... why do the reply and quote buttons not work?
Cheers
padbrides,
Looks like the reply button's working- it'll include quotes for you.
Craig
Looks like someone fixed it, but all my attachments disappeared... I'm trying to put them up again.
You can look back through the threads and see the reply or quote buttons haven't been used for a while.. what did you do? :)
Cheers
pabrides,
I guess CelNav fixed it.
Works fine now.
Craig
RE: THINK ABOUT IT - BigBill - 05-16-2021
(02-07-2021, 02:40 PM)I have always assumed the noon sight and a Polaris sight would be good for that. You could at least get latitude pretty well, if use of a timepiece is allowed, longitude follows. Then later, a series of sight reductions to narrow that down further. Funny, 'don't know your location on Earth', is the way many people assume CelNav is daily, when in reality, you are just reducing the uncertainty in your estimated position.
pabrides Wrote: If I disoriented you beyond doubt, so that you didnt know your location on earth, and if I dropped you in some ocean;
1... could you determine your approximate location, say within a few hundred miles, given a raft full of non-electronic navigation equipment and publications?
2... If yes, how would you go about it?