Reply
 
Thread Tools Display Modes
 
Old 12-19-2012, 10:26 AM   #61
Guru
 
MurrayM's Avatar
 
City: Kitimat, North Coast BC
Country: Canada
Vessel Name: Badger
Vessel Model: 30' Sundowner Tug
Join Date: Jul 2012
Posts: 3,325
Quote:
Originally Posted by RickB View Post
If you were halfway across the Pacific with no landmarks in sight and a 50 knot current developed from ahead or astern you wouldn't know about it unless you looked at your GPS and the boat would never know about it. The only thing that changes is the time it takes to go between A and B.
The Polynesians managed it.
__________________
Advertisement

__________________
"The most interesting path between two points is not a straight line" Murray Minchin
MurrayM is offline   Reply With Quote
Old 12-19-2012, 10:44 AM   #62
Scraping Paint
 
City: Fort Lauderdale
Vessel Model: CHB 48 Zodiac YL 4.2
Join Date: Oct 2007
Posts: 3,804
Quote:
Originally Posted by MurrayM View Post
The Polynesians managed it.
"You guys made way more sense arguing about anchors."
__________________

RickB is offline   Reply With Quote
Old 12-19-2012, 10:55 AM   #63
Guru
 
skipperdude's Avatar
 
City: Whittier AK
Country: USA
Vessel Name: Apache II
Vessel Model: 1974 Donald Jones
Join Date: Oct 2007
Posts: 3,147
From reading all the thoughts on this question I have gained a bit of insight.
I started a thread on a similar issue on running the boat at a given rpm to maintain the true hull speed.
Without being able to run at slack tide with no current.
Without a true speed Thur water. As available with a pito tube mounted on the hull.
I have decided to maintain a given rpm and currents and tides be dammed.
I will get from point A to B and just enjoy the ride.

Hey MurryM. what is that photo of in your avatar and why did you select it for a boating forum?
I don't have any problem with it just curious.

SD
__________________
If you can't repair it maybe it shouldn't be on the boat
skipperdude is offline   Reply With Quote
Old 12-19-2012, 10:55 AM   #64
Guru
 
MurrayM's Avatar
 
City: Kitimat, North Coast BC
Country: Canada
Vessel Name: Badger
Vessel Model: 30' Sundowner Tug
Join Date: Jul 2012
Posts: 3,325
Oh, and the Vikings did pretty good too.
__________________
"The most interesting path between two points is not a straight line" Murray Minchin
MurrayM is offline   Reply With Quote
Old 12-19-2012, 11:02 AM   #65
Guru
 
MurrayM's Avatar
 
City: Kitimat, North Coast BC
Country: Canada
Vessel Name: Badger
Vessel Model: 30' Sundowner Tug
Join Date: Jul 2012
Posts: 3,325
Quote:
Originally Posted by skipperdude View Post
Hey MurryM. what is that photo of in your avatar and why did you select it for a boating forum?
I don't have any problem with it just curious.
It's a piece of a beach on BC's north coast that I took while sea kayaking. We plan to use our 'new to us' vessel as a base camp, so we can explore even more such locations. The title and location is in my signature line.


Look for more in the future
__________________
"The most interesting path between two points is not a straight line" Murray Minchin
MurrayM is offline   Reply With Quote
Old 12-19-2012, 11:05 AM   #66
Guru
 
SomeSailor's Avatar
 
City: Everett, WA
Vessel Name: Honey Badger
Vessel Model: 42' CHB Europa
Join Date: Oct 2011
Posts: 784
Quote:
Originally Posted by Marin View Post
Then someone came back with how they don't ask their dog for advice, and it went on from there.
My dog is a 160# Newfy, and although they are known for their seamanship I try to refrain from asking his advice.

I think Marin trusts his canine counsel more than he should at times.
SomeSailor is offline   Reply With Quote
Old 12-19-2012, 11:15 AM   #67
Art
Guru
 
Art's Avatar
 
City: SF Bay Area
Country: USA
Vessel Model: Tollycraft 34' Tri Cabin
Join Date: Feb 2011
Posts: 7,981
How can there be any argument at all on this???

Carefully read my post # 54. Simple is as simple does!

1. Cruise with the current and faster "over-the-land speed" is realized, therefore using less fuel to travel a documented “land distance”.
2. Cruise against the current and slower "over-the-land speed" is realized, therefore using more fuel to travel a documented “land distance”.

As is depicted in my post # 54 there are some deep thinking (lol) processes required to make sure you consistently travel with the current... to help increase your “land speed” and therefore reduce your fuel usage. I’m sure every boater can figure those deep thinking processes out!

BTW, Marin (regarding your post # 55) my post # 54 does not pose theory – it states fact... just like this post!
Art is offline   Reply With Quote
Old 12-19-2012, 11:20 AM   #68
Guru
 
skipperdude's Avatar
 
City: Whittier AK
Country: USA
Vessel Name: Apache II
Vessel Model: 1974 Donald Jones
Join Date: Oct 2007
Posts: 3,147

19Skipperdude Talk about your unique rock formations what is this.


0:25WATCHED

Freaky Fossilized human boot/ shoe print. Time travel?


4,357 views Found this fossil impression of what appears to be a set of tracks or boot prints in stone in a small cove in Prince William Sound Alaska.

Sorry I didn't mean to hyjack this tread.
I should have posted this on another place.
Is this considered a form of thread creep?
__________________
If you can't repair it maybe it shouldn't be on the boat
skipperdude is offline   Reply With Quote
Old 12-19-2012, 11:22 AM   #69
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 13,714
skipperdude wrote;

"I have decided to maintain a given rpm and currents and tides be dammed.
I will get from point A to B and just enjoy the ride."

That's exactly what I do. But when something as interesting as this looms up ya just gotta think about it ... talk about it.

Not one of us would have thunk of all this stuff alone.

We can do lots of stuff here together that we can't do alone.

Rick your'e horney for anchors but you never had much or anything to say about anchors as I remember. I think there's more lurkers here than combatants.

Dogs ..... no I'm not going to go there.
__________________
Eric

North Western Washington State USA
Nomad Willy is offline   Reply With Quote
Old 12-19-2012, 11:26 AM   #70
Guru
 
SomeSailor's Avatar
 
City: Everett, WA
Vessel Name: Honey Badger
Vessel Model: 42' CHB Europa
Join Date: Oct 2011
Posts: 784
Quote:
Originally Posted by Marin View Post
Your theory will work where you are. It won't here, to a large degree, because for much of the coast there is no way to know exactly what the currents will do in a specific channel or pass because there are far too many of them to put in the current tables.
You need to update your chartplotter. Mine (Garmin) predicts the current flows and tides from the local stations and overlays those onto your display. It's handy to be able look ahead and realize you won't make it.

I also use sites like Dairiki to validate the predictions and then actual current reading from the local stations on my iPad/iPhone
SomeSailor is offline   Reply With Quote
Old 12-19-2012, 11:53 AM   #71
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 9,996
Greetings,
Mr. SS. Newfoundlander would be the most polite term for your dog. I think Newfy is considered a derogatory term according to my sources but I guess the most PC term would be Newfoundlander and Labradorian.
__________________
RTF
RT Firefly is offline   Reply With Quote
Old 12-19-2012, 12:02 PM   #72
Guru
 
skipperdude's Avatar
 
City: Whittier AK
Country: USA
Vessel Name: Apache II
Vessel Model: 1974 Donald Jones
Join Date: Oct 2007
Posts: 3,147
Right on RT.

It is pronounced
New fund lander.
Not New found lunder
Not New found lund.

New fund land with the accent being on land not like New Englund

Not sure about the little pronouncement icons. sort of like
Illinois or New Orleans.

Some get irate if not pronounced as the locals



sd
__________________
If you can't repair it maybe it shouldn't be on the boat
skipperdude is offline   Reply With Quote
Old 12-19-2012, 12:14 PM   #73
Guru
 
MurrayM's Avatar
 
City: Kitimat, North Coast BC
Country: Canada
Vessel Name: Badger
Vessel Model: 30' Sundowner Tug
Join Date: Jul 2012
Posts: 3,325
skipperdude; that is truly weird. Could it be a Native petroglyph?
__________________
"The most interesting path between two points is not a straight line" Murray Minchin
MurrayM is offline   Reply With Quote
Old 12-19-2012, 12:25 PM   #74
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,633
Quote:
Originally Posted by FlyWright View Post
I believe Marin is right and I'll attempt to prove it mathematically.

Imagine cruising a 2 NM course, round trip at 6 kts with no current. Each leg will take 20 minutes (2/6=.333x60=:20) for a :40 round trip.

Now cruise the same course with 2 kts of current with you and against you. Leg 1 is into the current yielding a 4 kt speed over 2 miles and it takes you 30 minutes. (2/4=.5x60=:30)
Leg 2 is completed at 8 kts with the push from the current and takes you 15 minutes.(2/8=.25x60=:15) Adding leg 1 and 2 is :30+:15=:45.

The same course traveled with the 2 kt current took 5 minutes longer. The reason is that when the current is helping you, you have less time to benefit from it. When it slowing you down, the effect of the current hits you over a longer span of time.

That's this engineer's take on it anyway.
And that is 1000% correct and end of discussion!!!
Baker is offline   Reply With Quote
Old 12-19-2012, 12:28 PM   #75
Guru
 
Moonstruck's Avatar
 
City: Hailing Port: Charleston, SC
Country: USA
Vessel Name: Moonstruck
Vessel Model: Sabre 42 Hardtop Express
Join Date: Nov 2008
Posts: 7,849
Quote:
Originally Posted by Baker View Post
And that is 1000% correct and end of discussion!!!
Two pilots don't make a right.
__________________
Don on Moonstruck
Sabre 42 Hardtop Express & Blackfin 25 CC
When cruising life is simpler, but on a grander scale (author unknown)
http://moonstruckblog.wordpress.com/
Moonstruck is offline   Reply With Quote
Old 12-19-2012, 12:33 PM   #76
Guru
 
AusCan's Avatar
 
City: Adelaide
Country: Australia
Vessel Name: Kokanee
Vessel Model: Cuddles 30 Pilot House Motor Sailer
Join Date: Jul 2012
Posts: 2,097
To clarify by "hull speed" I meant normal maximum hull speed.
AusCan is offline   Reply With Quote
Old 12-19-2012, 12:42 PM   #77
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,633
Quote:
Originally Posted by Moonstruck View Post
Two pilots don't make a right.


Now....I got one for y'all??? Does cross current affect your SOG at all??? On the circular slide rule, it says it does not. But I disagree.
Baker is offline   Reply With Quote
Old 12-19-2012, 01:02 PM   #78
Art
Guru
 
Art's Avatar
 
City: SF Bay Area
Country: USA
Vessel Model: Tollycraft 34' Tri Cabin
Join Date: Feb 2011
Posts: 7,981
Quote:
Originally Posted by Baker View Post
And that is 1000% correct and end of discussion!!!
That is only end of discussion if you do not plan correctly to exclusively travel with the current... read my posts #’s 54 and 67.

To travel against the current is unnecessary unless your schedule demands that you must travel against the current too, in order to meet time obligations. In that case I say you are on some fashion of a work party, rather than a pleasure party!
Art is offline   Reply With Quote
Old 12-19-2012, 01:06 PM   #79
Enigma
 
RT Firefly's Avatar
 
City: Slicker?
Country: Bumpkin?
Join Date: Oct 2007
Posts: 9,996
Greetings,
Mr. Baker. OK...Brain in gear...
Try to remember something about vectors...
Conclusion: Can't remember much but if the cross current is at 90 degrees, the only thing I think would have any effect would be a slight increase in drag due to the hull slewing sideways. Any angle other than 90 degrees to the beam will either add or subtract to SOG.
Good golly, thinking is tough!
__________________
RTF
RT Firefly is offline   Reply With Quote
Old 12-19-2012, 01:09 PM   #80
Guru
 
MurrayM's Avatar
 
City: Kitimat, North Coast BC
Country: Canada
Vessel Name: Badger
Vessel Model: 30' Sundowner Tug
Join Date: Jul 2012
Posts: 3,325
Quote:
Originally Posted by Baker View Post
Now....I got one for y'all??? Does cross current affect your SOG at all??? On the circular slide rule, it says it does not. But I disagree.
When figuring out channel crossings while sea kayaking, we measured the distance of drift caused by current as if we paddled straight across on a compass bearing. The wider the channel, the greater the distance "off target" we would be taken by the current. This longer distance was what we used to estimate how long it would take, because to get to our intended destination we would have to angle into the current an equal and opposite angle to the angle of drift, to counteract drift. This meant a much longer crossing time than if we could simply paddled straight across. So, in this case, SOG is definitely affected.
__________________

__________________
"The most interesting path between two points is not a straight line" Murray Minchin
MurrayM is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 06:17 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012