VoyForums
[ Show ]
Support VoyForums
[ Shrink ]
VoyForums Announcement: Programming and providing support for this service has been a labor of love since 1997. We are one of the few services online who values our users' privacy, and have never sold your information. We have even fought hard to defend your privacy in legal cases; however, we've done it with almost no financial support -- paying out of pocket to continue providing the service. Due to the issues imposed on us by advertisers, we also stopped hosting most ads on the forums many years ago. We hope you appreciate our efforts.

Show your support by donating any amount. (Note: We are still technically a for-profit company, so your contribution is not tax-deductible.) PayPal Acct: Feedback:

Donate to VoyForums (PayPal):

[ Login ] [ Contact Forum Admin ] [ Main index ] [ Post a new message ] [ Search | Check update time | Archives: 1, 2, [3], 4 ]

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Date Posted: 10:45:57 10/07/08 Tue
Author: RadioRay (GPS, Celestial and Any Single Point of Failure)
Subject: Re: Philosophy, GPS and the sailor
In reply to: TomH 's message, "Re: Philosophy, GPS and the sailor" on 08:05:46 10/07/08 Tue

This is a good question. GPS is a marvel. The ability to know your position to less than the size of your boat in zero visibility is simply amazing to me. However, is should not be the only navigation method in use. You do want redundancy. The GPS is as you've pointed-out a military system first and foremost, owned and operated by a government which has a large and growing list of enemies many of whom would be quite capable of at least area denial of GPS navigation through everything from local jamming to satellite attack. I'd hate to be out on the Big Blue with ONLY a GPS during a war, or naval exercise with jamming or as posted earlier, even accidental interference...

Celestial is fun, though I also find that a 'fix' of my position is more to tell me under five or ten miles, my location. Yes, there are far better fixes that those more skilled than I can produce, on a bouncy little sailboat, single handing and with plenty to do other than trolling for seasickness from staring at my calculations on a paper tablet. Another, faster option is sextant and navigation software for the times when you have a working , programmable calculator, PDA or laptop. Know how to do it on paper, but these little programmes are really excellent and can take your 'sights' and reduce them to the chart in under a minute, so multiple, averages sights on celectial objects can be rapidly averaged in the software and displayed. Because it takes much of the pencil scratching and TIME out of celestial, you're more likely to be taking many, many shots and averaging them for better accuracy than you would do if reducing your sights using only paper and pencil.

However, when you're trying to find a continent, a few miles here or there is not such a bad thing! ;^)


>RadioRay ..._ ._

Ps. Funny story: when I lived ashore I was practicing with my Soviet Navy surplus CNO-T sextant (fine instrument, BTW) in the yard of my rental apartment. The owner's rather tasty 20 year old daughter spied me curiously as I was peering into this strange object:

Girl: "What it that?"

Sailor: "It's a sextant."

Girl hears "It's a SEX....." and frowns suspiciously.

Sailor: "You've heard of navigating by the stars? Well this is a sextant, used for measuring angles up to the stars for navigation on my sailboat."

Girl: (I KNOW I heard him say something to me about SEX. That dirty old man.) Frowning // "Uh-huh"

-- Unfortunately I neither convinced her about my need for navigation or sex. Though I did have my preference. --

Ignorance is bliss and she was right about one thing: I would happily have remained ignorant of my 'position' at the time, in exchange for some blissful position with her, but that's a constant state of mind, especially it seems, for sailors.

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Replies:

  • Re: "receiver" -- Zombi (don't believe everything you know.), 14:56:24 10/07/08 Tue
  • Slight Correction... -- Mark D, 11:41:57 10/08/08 Wed
    [ Contact Forum Admin ]

    Forum timezone: GMT-8
    VF Version: 3.00b, ConfDB:
    Before posting please read our privacy policy.
    VoyForums(tm) is a Free Service from Voyager Info-Systems.
    Copyright © 1998-2019 Voyager Info-Systems. All Rights Reserved.