|
"otnmbrd" wrote in message ink.net... It's not so much you should use your charts with a "grain of salt", as you need be aware that they are not perfect and if you have any doubts, you should use ALL means at your disposal, especially the "Mark I eyeball". If you see discolored water, obvious current swirls, disturbed wave action, (to name some) in a particular area, or your wake changes and you bog down ..... these are indications that something may not be as the chart suggest, and it doesn't matter whether you're using GPS, celestial, radar, etc., for your navigation, you may want to stop or reverse direction till you can figure things out or find a better route. otn Got it...3AM blowing 35...12 foot seas...Check for the disturbed waves and current swirls...yeah right. Watch the little birds...if they land it probably is not deep. Still at the old game otnmbrd? Would you really reverse course under those conditions? Would you turn the boat across the wind? Jim Donohue |
On Sun, 16 Jan 2005 19:31:22 GMT, "Roger Long"
wrote: Yeah, the QEII (I think) ran aground about 20 years ago just off the Elizabeth Islands on Cape Cod and in one of the most heavily traveled areas of New England. The chart turned out to be wrong. -- Much more recent than that. I kept a copy of the last chart edition before the grounding just to show people. It was surveyed quite promptly after the grounding. THe new edition looks very different. BTW, the previous survey was not 100 years old. It was 1939. WW2 intervened or I expect the job would have been completed. Rodney Myrvaagnes NYC J36 Gjo/a Capsizing under chute, and having the chute rise and fill without tangling, all while Mark and Sally are still behind you |
|
Jim Donohue wrote:
Got it...3AM blowing 35...12 foot seas...Check for the disturbed waves and current swirls...yeah right. Watch the little birds...if they land it probably is not deep. Still at the old game otnmbrd? Would you really reverse course under those conditions? Would you turn the boat across the wind? Jim Donohue LOL I see you're still looking for the simple cure-all answer to navigation. Sorry Jim, it doesn't exist. You'll note I said use ALL means at your disposal. Sometimes those means are limited due to conditions, be they visibility or sea conditions. However, frequently there are any number of things you can look for under many varied conditions which may help you determine that you are "standing into danger" and your god, GPS will not tell you these things. So, yes, I'm still up to the old games ..... if in doubt, stop, turn around, sail across the wind, if those things are possible. Don't keep going blindly based on a GPS fix ..../ use whatever other tools may be available to you, be they natural, mechanical, or electronic. Only a fool relies on one means of navigation and only a bigger fool discards all the older methods which served and still serve, many of us well, even if in a limited capacity. G Maybe someday you'll learn to take your eyes off the GPS and see what's going on around you. otn |
On Sun, 16 Jan 2005 23:17:11 GMT, "Roger Long"
wrote: That rings a bell and I think you might be right. The shoal being shallower than charted may have been a secondary factor. I don't think it would have been GPS in those days. Probably Loran. Can't tell what you are talking about. Both the QE2 and Nantucket shoals incident are quite recent. The QE2 was a chart problem, since corrected, and had nothing to do with autopilot or any other automated gear. The Nantucket shoals incident was from a system that ran on DR for 600+ miles with the GPS disconnected. Rodney Myrvaagnes NYC J36 Gjo/a Capsizing under chute, and having the chute rise and fill without tangling, all while Mark and Sally are still behind you |
I think that incident occurred several years ago. The QE2 did suffer from a mysterious power
ailment and found itself adrift for several hours in the 1980's while cruising thru an area known as the Bermuda Triangle... but I will leave it at that. The QE2 grounding was also found to be exacerbated by a previously unknown condition the ship had while at speed, it was found to "squat" down 6 feet. "Roger Long" wrote: Yeah, the QEII (I think) ran aground about 20 years ago just off the Elizabeth Islands on Cape Cod and in one of the most heavily traveled areas of New England. The chart turned out to be wrong. |
On Sun, 16 Jan 2005 11:04:38 -0500, "Glenn Ashmore"
wrote: http://www.goupstate.com/apps/pbcs.d...60/1051/NEWS01 Not that any of us will be cruising at 30 knots 500 feet below the surface but navigating soly by GPS you are just as blind. Many of the charts we use are from surveys over 100 years old. If I might use an analogy. How many out there are prepared to drive their car using GPS only? Jack __________________________________________________ Jack Dale Swiftsure Sailing Academy Director/ISPA and CYA Instructor http://www.swiftsuresailing.com __________________________________________________ |
What I recall reading about the QE2 hitting the rock there (divers confirmed
that there was recent bottom paint scuffed on the rock, and I don't think there was an indication that the rock had less water than the chart showed) is that she was running at too much speed for that little clearance between hull and sea floor. The hydrodynamic forces from speed in shallow water will pull the stern down. I see this happen frequently, and when it does, besides thinking about QE2, I know I'd better head to deeper water, or slow down. I just couldn't believe the captain didn't think about this when he was steaming along near the rock. "Roger Long" wrote in message ... Yeah, the QEII (I think) ran aground about 20 years ago just off the Elizabeth Islands on Cape Cod and in one of the most heavily traveled areas of New England. The chart turned out to be wrong. -- Roger Long "Glenn Ashmore" wrote in message news:mgwGd.21097$EG1.17828@lakeread04... http://www.goupstate.com/apps/pbcs.d...NYT02/50115036 0/1051/NEWS01 Not that any of us will be cruising at 30 knots 500 feet below the surface but navigating soly by GPS you are just as blind. Many of the charts we use are from surveys over 100 years old. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
The Nantucket shoals incident was from a system that ran on DR for
600+ miles with the GPS disconnected. THAT is the story I was remembering. None of the crew noticed. No one was running their own plot. |
When did these incidents happen? I lived on the Cape in the late 70's
so I may be transferring the memory back to that association. When did they start installing GPS on big ships? -- Roger Long "Rodney Myrvaagnes" wrote in message ... On Sun, 16 Jan 2005 23:17:11 GMT, "Roger Long" wrote: That rings a bell and I think you might be right. The shoal being shallower than charted may have been a secondary factor. I don't think it would have been GPS in those days. Probably Loran. Can't tell what you are talking about. Both the QE2 and Nantucket shoals incident are quite recent. The QE2 was a chart problem, since corrected, and had nothing to do with autopilot or any other automated gear. The Nantucket shoals incident was from a system that ran on DR for 600+ miles with the GPS disconnected. Rodney Myrvaagnes NYC J36 Gjo/a Capsizing under chute, and having the chute rise and fill without tangling, all while Mark and Sally are still behind you |
| All times are GMT +1. The time now is 12:23 AM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 BoatBanter.com