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Old 30 March 2006, 02:56   #11
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Quote:
Originally Posted by roycruse
How many peoiple have ever had GPS failure ??? I havnt had GPS failure EVER - on land, in the air, or at sea. In over 10 years of using them.
Chart plotters are pretty reliable these days, but not infallible. Plenty of people have had various electrical problems that could leave a chartplotter out of action. Hand held GPSs are a good backup, and also generally reliable, but have limited battery life (remember, your main power is knackered at this time too!).

The likelihood of failure may be low, bur I would still fit a magnetic compass as a back up.
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How many people (other than when on a training course) have ever needed to follow a bearing with a compass. If im navigating to an out of site mark - I have my plotter on a screen that simply tells me how many degrees left or right I need to turn - easy -
On longer passages I actually prefer to steer by compass rather than constantly staring at a screen. It also avoids constantly correcting course to get on the "correct" line just because the GPS says so.

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Old 30 March 2006, 03:15   #12
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There is something very reassuring about being able to compare the GPS or to a magnetic compass when your stuck in thick fog. An ordinary orienteering compass is pretty fool proof and having carried one underwater for 10 years pretty water proof too if you don't want to rush to one of the yachtie ones like JK suggested.

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Old 30 March 2006, 04:14   #13
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Quote:
Originally Posted by roycruse
How many peoiple have ever had GPS failure ???
Agree, the electronics are pretty reliable nowadays. But how reliable is the grey mush between your ears? If it involves electronics or human input, IT CAN GO PETE TONG!

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Originally Posted by roycruise
...I rely heavily on the moving map charts on the plotter - theres no way you could do this kind of ad hoc high speed in close stuff without being able to know at a glance whats ahead of you.
Moving map displays are very useful, but again its interpretation of what you see. You should be looking ahead most of the time, not staring at a screen. It sounds to me like you are getting too confident with gps. Take a step back and prepare a plan for your trip. It doesn't take 5 minutes and is alot more satisfying than running a technology trip.

Quote:
Originally Posted by roycruise
How many people (other than when on a training course) have ever needed to follow a bearing with a compass.
A couple of times in anger yes. Could you do it?
We take great pride in our activity, and part of the fun is to be seen doing the right thing. It is good entertainment watching somebody else making a fool of themselves with poor seamanship.

Now before anyone gets on their soapbox, I am not advocating turn all gps's off and navigate by sun and star, just bear in mind that gps nor its operator is infallable. Have a backup plan, and be capable to use it effectively.

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Old 30 March 2006, 04:54   #14
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I never said don't carry a compass - in fact I have said in a previous post on a different thread that you should never leave shore without one.

All I was saying is that in all the time of carrying a compass I have never actually used one for steering by.

I don't drive my RIB like a video game - staring at the screen - I glance at it no more frequently than a rear view mirror when driving a car. I am very much looking where I'm going - but often you cant sea under the water and even when you can its very difficult to judge the exact depth.

I took my dad on a trip from Falmouth to Fowey last year - when doing these coastal trips I have the chart plotter zoomed right in so its only giving me info on whats directly ahead of me - at this zoom level you also get a circle around your position giving you the gps accuracy - I, after a lot of testing and trial and error, comparing the moving charts with my actual position and the readings from the depth sounder, now trust this position info completely and using it in conjunction with the sounder and visual cues from my observations can be confident ands get in real close with the coastline - nipping in between exposed rocks etc and getting a great view rather than missing it all going round a cardinal mark half a mile out. My dad is a far more experienced boatman than me having done the same trip many times in powerboats and yachts. The one thing he said to me after the trip was "WOW, Ive never been that close to the coastline before" That was the power of using a chart plotter that you could never do with a compass and map.

Anyway - my ramblings are slightly off the thread topic - electronic compass ?????? cant see the point in them, at all. I am a complete gadget freak and the first time I ever saw one in a shop - I thought WOW an electronic compass - bought it - fitted it to the dash - drove round in circles a few times in a car park to calibrate it. then a few weeks later - the batteries where dead - it spent a couple more weeks stuck on the dash not working - then I threw it away. Pointless.

Electrickery is only useful when it has an advantage over the non electrical counterpart - I cant see any advantages of an electrical compass over a mechanical one.
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Old 30 March 2006, 05:39   #15
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Hi Roycruse,
Sorry if it sounded like a rant, it wasnt intended that way. Just a reminder that leaving little room for error is not good. I too use a chart plotter but never rely on it alone. (if I can help it!).
I often put a cover over it and practice non gps navigation. Its actually good entertainment if you have the time.
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Old 30 March 2006, 06:54   #16
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Quote:
Originally Posted by roycruse
I cant see the point in a compass at all on a RIB other than if you have gps failure in fog or out of sight of land (ie as an emergency safety device). How many peoiple have ever had GPS failure ??? I havnt had GPS failure EVER - on land, in the air, or at sea. In over 10 years of using them.
Especially if you dont also have a radar reflector in the fog
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Old 30 March 2006, 08:18   #17
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Yes they're great value and plenty more in stock. We also have some excellent 'bent-box' specials on Steiner for the big spenders like Codders. (Looks like I owe JK £100 now - will upgrade shortly, honest)

Open to negotiaton on the Steiners from Ribnet people (maybe a free float strap?) Give me a call on 01256 478000 if you're interested. Can also do carriage-free for pickup at Solent meet-ups.

Prefer regular compass myself - as Tim says, digital can mean something else to go wrong.
Just looked at your site and realised it was you I bought my Steiners from - I think!!!
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Old 31 March 2006, 01:26   #18
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Quote:
Originally Posted by Pete7
There is something very reassuring about being able to compare the GPS or to a magnetic compass when your stuck in thick fog. An ordinary orienteering compass is pretty fool proof and having carried one underwater for 10 years pretty water proof too if you don't want to rush to one of the yachtie ones like JK suggested.

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Old 31 March 2006, 03:29   #19
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Yes, I was only watching a Discovery prog on Sky this morning on the subject, I know it's an aside, but apparently the earths magnetic field has weakened more over the past 300 years than in the past 5,000 years. There are several anomalies in the Southern hemisphere that give a 30 degree deviation, these are getting larger, suggesting a pole reversal. These happen every 10,000 years or so, apparently we are due for one soon

Soon” meaning like a few thousand years. Thanks for all the replies I think I will ditch the digital compass idea and stick to a consol mounted for direction and a hand held for fixing points.

BootNeck
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Old 31 March 2006, 06:00   #20
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Fred, that's an interesting site. Well found.
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