Paper Charts and GPS

[GordMay]

The USS “San Francisco”, a $1 billion fast-attack nuclear submarine, struck an undersea mountain on January8, 2005.

They were passing through the Caroline Islands (enroute from Guam south to Australia), at a depth of 525 feet, when 7,000 tons of steel, moving at flank speed, with 137 souls on board, came to a crashing halt.

The “San Francisco” was using a classified, best-available Navy chart (which showed nothing like a sea-mount), and steering a route sent from headquarters, when it ran into the mountain .

There were other charts on board that clearly show a navigation hazard near where the San Francisco grounded. And the Navy says Captain Mooney and his team were required to look at all the charts, not to rely on the accuracy of just the one.

➥ http://www.nytimes.com/2005/05/18/na...rash.html?_r=1

➥ Who's To Blame For Sub Accident? - CBS News

➥ USS San Francisco (SSN-711) - Wikipedia, the free encyclopedia

[bayview]

I see the preliminary recommendations from the inquiry into the Flinders Island tragedy have just been released. Makes interesting reading with regard to this thread.

Take note of item '1'. Its starting to look like techo wizzo stuff is being relied on a tad too much.

2009_CYCA_FlinderIslet_Announcement

[Pblais]

Its starting to look like techo wizzo stuff is being relied on a tad too much.

Perhaps so. Perfect information seems to be an assumption or at least a great expectation. GPS is exceptionally good, but maps are far less so. Sorry folks, the far corners of the world not involved in the global economy are in the "couldn't care less" category as far as updated charts. Guess what places are where you really want to be are? You need to deal with imperfect information or you are at your peril. It's still possible to navigate in an imperfect world.

[alan2]

My knowledge and understanding of navigation is likely quite limited, however that aside, it sounds as if EVERYONE on that boat is lucky to be alive, very lucky.

Re R.B. Emerson's, "we are one battery failure from the age of sail" is likely a lot closer to the mark than some would like to admit or are comfortable with. Nevertheless, it remains true, all to true, and the ripples in the pond extend quite far from things involving sailing. Such considerations as are involved with this get quite far from the scope of discussions here though.

Happy holidays to all.

[btrayfors]

Originally Posted by alan2

My knowledge and understanding of navigation is likely quite limited, however that aside, it sounds as if EVERYONE on that boat is lucky to be alive, very lucky.
....

Alan,

You're absolutely right!!

By chance, I know an engineer who was deeply involved in this incident and it's aftermath. By chance, I received an email from him this morning, responding to an email I'd sent him referencing the news story.

He commented, among other things, that "Those guys came about as close to loosing the boat as you can come."

Such disasters are not all because of too much reliance on "fancy toys"...though there are lots of "GPS-assisted disasters" one can point to -- but just underscore the fact that there's no room on a boat for sloppy navigation techniques. Sooner or later it's gonna result in disaster.

Happy Holidays,

Bill

[clearsea]

Originally Posted by Lodesman

Your points bring up another question - how many who use paper only have a back-up? What do they use?

Hand-held GPS (wink).

[bayview]

Originally Posted by Lodesman

. Your points bring up another question - how many who use paper only have a back-up? What do they use?

An Atlas, or if that fails look over the side of the boat and make your own.

[Factor]

Originally Posted by bayview

I see the preliminary recommendations from the inquiry into the Flinders Island tragedy have just been released. Makes interesting reading with regard to this thread.

Take note of item '1'. Its starting to look like techo wizzo stuff is being relied on a tad too much.

2009_CYCA_FlinderIslet_Announcement

Ah - no thats just what the CYCA say they think happened. I think I may wait for the Police brief to the coroner to be tabled before I draw any conclusions. And in any event - even if that were true to extrapolate that comment about that boat more broadly is without foundation or basis.

And further - If someone who races at that level was driving by chart and they were not one of the deceased then I would expect to see a finding of culpability.

But like I said - I dont think I will place too much store in a report that wasn't based on any of the accepted rules of evidence, had no opportunity for transparent and rigorous cross examination, and does not publish its unedited document. They may be right - they may have done a wonderful job, its just that I dont know that they have and cant objectively satisfy myself to that extent

The problem with these sorts of disasters aside from the deep personal tragedy is that another phalanx of rules will enter racing and then find their way into my cruising life as people like YA and YQ like to think that they are the spokespersons for sailors in Australia and Queensland. .

[Factor]

Originally Posted by Factor

And further - If someone who races at that level was driving by chart and they were not one of the deceased then I would expect to see a finding of culpability .

That word should read chartplotter

[alan2]

Interestingly or troublingly, it seems that more and more vessels clear port without a sextant, and or the charts, tables that would be used with same, to determine one's position. As I understand, possibly incorrectly, this applies to naval vessels as well as commercial ships.

[IslandHopper]

Originally Posted by alan2

Interestingly or troublingly, it seems that more and more vessels clear port without a sextant, and or the charts, tables that would be used with same, to determine one's position. As I understand, possibly incorrectly, this applies to naval vessels as well as commercial ships.

I cannot comment on the charts, but as far as the Sextant goes, you are correct. As far as the world's Navy's go, most do not teach Celestial Nav anymore, and quite rightly so, a near miss is just not acceptable, and by that i do not mean what you are aiming at but where you fire from, which needs to be accurate, you cannot hope to hit a target with a missile if you don't know where it was fired from, and a Sextant will NOT give you that sort of precision....

In the commercial sector where i work, Sextants are still placed on new builds, but most do not know how to use them correctly because they are irrelevent to the day to day requirements. I work in the Offshore Oil and Gas Industry and a Sextant is usless in the precision we are required to work to. Unfortunatly the Sextant has no place in the commercial world of shipping these days due to the enforcement of strict time tables, and been within 20 to 30nm (if you are consistantly that good) of the shortest course to your destination is unacceptable.

We still do a Sun Run Sun when able, and we still use a Polaris for Compass corrections, but it is never used in a practical way and only entered in the compass log because we are still required to carry one.

Unfortunatly the Sextant is slowly being reduced to the hobbist... i know how to use one as it was drummed into me at maritime collage years ago, and kicked into me as a second mate, but the reality is, it just does not apply to todays requirements....

[s/v Beth]

I think the loss of c-nav in the commerical shipping is sad. That said, what are they doing with all the old sextants? Can you snag me one?

[alan2]

Originally Posted by s/v Beth

I think the loss of c-nav in the commerical shipping is sad. That said, what are they doing with all the old sextants? Can you snag me one?

If you go to ebay.com, type in marine sextant you will find, some offered. The story, which I can neither confirm nor show to be false is that the instruments offered come from vessels that went through "breakers yard", were salvaged and offered for sale. The claim is that they are all in good condition/very good, of course, re such matters, it might be a question of How One Spells Good or Very Good Condition.

I have absoluteley no idea as to how the cookie might crumble in the case of a purchaser feeling that a sextant he bought was not as advertized. As for U.S. Navy sextants, the Mark 3 I believe was the last of the ones they had, I saw one of them offered, a while back, on ebay. I think that the thing went for around $500, though that's a guess.

$600 buys you a brand new with a 1 year warranty, from Celestaire, the Astra 111B. $800 buys the Astra 111 Professional, or if you feel really flush, C & P and the Tamaya are offered too, the price is about double or more. Some of these also appear on ebay.com, but you are buying Sight Unseen.

Based on my VERY LIMITED EXPERIENCE one can shoot the sun and moon with the Davis Mk. 15 (Plastic) too, for less than $200. Pay your money and take your choice.

[alan2]

Island Hopper:
I have no doubt that you are right on regarding the accuracy of sextant shots and the positioning obtained there from, including that the navies of the world aren’t teaching it any more either, it just won't cut it in the world today, which might or might not be sad.

Within the limits of battery power and other considerations, sun spots and such, an $80 hand held GPS unit will produce lat and long position data well within 10 meters, within a minute of so. There is no sextant in the world that will come anywhere close to that accuracy, and then there is the time involved. Seems like a dead loss from start to stop, so long as the electronics work.

I just fool around with celestial navigation, when I can get to the beach, not all that often unfortunately. When I do sun and moon or moon and planet shots, assuming that I read the Nautical Almanac tables correctly, not always the case, and also assuming that I didn't blow the LOC sight reduction calculations by punching the wrong key on my calculator, again not always the case, I usually get estimated positions within 5 NM of a Known Position or GPS Fix. That strikes me as pretty good, though how it would strike people who know what they are doing, who knows.

Anyhow, having said the above, Celestial Navigation isn't that hard to get some understanding of, if I could do it, most reasonably intelligent and interest persons could too. It‘s also a classical skill, and in-so-far as that goes, it strikes me as worth maintaining, even if only as hobby, possibly like shooting targets with the long bow. If I had to hunt to feed myself, I'd much rather hunt deer with a 30 caliber rifle, but should none be at hand, that long bow could suffice.

[Lodesman]

Originally Posted by alan2

Island Hopper:
I usually get estimated positions within 5 NM of a Known Position or GPS Fix. That strikes me as pretty good, though how it would strike people who know what they are doing, who knows.

I'd estimate 5-mile accuracy to be typical for the average user. A meticulous person who practices daily might see 2 NM accuracy or slightly better. This is more than suitable to get you to within sight of land, then a sextant can be used for visual fixing (with typical visual-fix accuracy).