If it's not luffing, it's helping? - SailNet Community
 
LinkBack Thread Tools
post #1 of 9 Old 03-11-2012 Thread Starter
Member
 
steveg353's Avatar
 
Join Date: Jun 2008
Location: Houston TX
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
 
If it's not luffing, it's helping?

This question pertains to motor sailing directly into the wind with mainsail only.
Is it true that if you pull the traveler all the way over(whichever side seems closer to windward) and sheet in tight, that as long as the main is not luffing, it is helping to move the boat forward. I was told that if you cannot “hear” the sail, it is helping.
It feels like it helps to me but I wanted to see what the salts had to say about it.
I have a trip this week that, according to the reports, I will be running about 20 miles dead into the wind in a very busy ship channel.
steveg353 is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 9 Old 03-11-2012
Just another Moderator
 
Faster's Avatar
 
Join Date: Sep 2005
Location: New Westminster, BC
Posts: 16,382
Thanks: 101
Thanked 304 Times in 294 Posts
Rep Power: 10
     
Re: If it's not luffing, it's helping?

If you're truly "head to wind" and haul the traveller to one side or the other to stop the noise I'd say it's just drag.. if your apparent wind is, say, 20 or 25 degrees off the bow then you're probably getting some drive.

In any event it's WAY better for the sail to stop the luffing, and way easier on the nerves and ears. However if you know the whole trip is upwind and it's not rough, I'd douse the sail. If it's rolly then there's a stabilizing effect that's worthwhile, as long as you're not beating the sail to death.

Ron

1984 Fast/Nicholson 345 "FastForward"

".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
Faster is offline  
Quote Quick Reply Share with Facebook
post #3 of 9 Old 03-11-2012 Thread Starter
Member
 
steveg353's Avatar
 
Join Date: Jun 2008
Location: Houston TX
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
 
Re: If it's not luffing, it's helping?

That is what I was wondering...does it cause forward drive or dreaded drag when the sail is tight and silent. Hopefully, the wind will be off the nose enough to help but I'm pretty sure the diesel is going to get a workout this week.
I love my diesel...I just hate using it.
steveg353 is offline  
Quote Quick Reply Share with Facebook
post #4 of 9 Old 03-11-2012
Senior Member
 
overbored's Avatar
 
Join Date: Oct 2010
Location: Dana Point, Ca
Posts: 1,133
Thanks: 1
Thanked 54 Times in 54 Posts
Rep Power: 5
 
Re: If it's not luffing, it's helping?

Quote:
Originally Posted by steveg353 View Post
That is what I was wondering...does it cause forward drive or dreaded drag when the sail is tight and silent. Hopefully, the wind will be off the nose enough to help but I'm pretty sure the diesel is going to get a workout this week.
I love my diesel...I just hate using it.
it depends on the wind speed and the angle of the wind if you are motoring at lets say 6 kts and the wind is on the nose then it is drag. if you are motoring at 30 dergees to the wind and motoring at 4 kts and the wind is blowing 20 then it maybe helping if the wind is only 6kts then it is drag. basicly if you are motoring at a given speed that there is not enough wind to make the same speed while under sail alone then the sail is drag.

"FULL TILT II" 2011 BENETEAU FIRST 30
"FULL TILT" SOVEREL 33
"GOLD RUSH" PRINDLE 16
overbored is offline  
Quote Quick Reply Share with Facebook
post #5 of 9 Old 03-11-2012
Senior Member
 
Join Date: May 2006
Posts: 825
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 10
 
Re: If it's not luffing, it's helping?

Not sure about the above. Because of the motoring the apparent wind moves forward and increases. As a result one might sail as if in 10 knots v 6 say at 4
instead of 2. The drive the sail produces depends on the angle to the apparent wind, and therefore requires the true wind to be somewhat further abeam. It may be that at 30 apparent you get drive whereas at 10 you get less drive than drag. In practice if you are getting more speed than the revs of the motor would give some of the force is coming from the sail as a result of the apparent wind increasing. Often the revs may be as low as 1000. However you still require an apparent wind angle which produces a force with a forward component. This may be say 30 meaning the twa is greater.
If the wind is in fact dead ahead not just light having the motor on will increase its strength but not produce a force on the sail other than drag think flags. Holding the boom to windward would produce a backward force.
chris_gee is offline  
Quote Quick Reply Share with Facebook
post #6 of 9 Old 03-11-2012
Senior Member
 
Join Date: Sep 2006
Location: Texas
Posts: 526
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 9
 
Re: If it's not luffing, it's helping?

The science factor is if the vector of force on the sail is forward of abeam, then it is helping, (you get better gas milage if too low to increase speed).

The Sun has Risen on a New Day filled with the Promise of Adventure.
CapnBilll is offline  
Quote Quick Reply Share with Facebook
post #7 of 9 Old 03-11-2012
Senior Member
 
Join Date: May 2002
Posts: 2,669
Thanks: 4
Thanked 29 Times in 27 Posts
Rep Power: 14
 
Re: If it's not luffing, it's helping?

I can't explain the theory, but I have done a lot of motorsailing up and down the Chesapeake, alone as well as in company of other boats, and can say that motorsailing increases speed and saves significantly on fuel. Also, you can motorsail much closer to the wind than you can sail. I don't think you gain by moving the traveler hard to windward, although you can prevent the sail from luffing that way, and I do it occasionally, when I'm motorsailing head-to-wind, or nearly so, in a narrow channel, where I don't have room to tack. If you have room to tack, the better choice is to approximately center the boom, or "cheat" it a little to windward, and then motorsail at an angle to the wind that produces good drive from the sails and good speed. If you tack with the wind shifts, you'll help yourself even more. Even though you will add distance by tacking back and forth, you'll gain enough in speed and fuel savings to make it worthwhile.
Sailormon6 is offline  
Quote Quick Reply Share with Facebook
post #8 of 9 Old 03-11-2012
Senior Moment Member
 
SloopJonB's Avatar
 
Join Date: Jun 2011
Location: West Vancouver B.C.
Posts: 11,329
Thanks: 59
Thanked 65 Times in 62 Posts
Rep Power: 4
 
Re: If it's not luffing, it's helping?

Quote:
Originally Posted by Sailormon6 View Post
can say that motorsailing increases speed and saves significantly on fuel. Also, you can motorsail much closer to the wind than you can sail.
That's essentially why motorsailors were created in the first place. You get a much smoother and less rolly ride as well

I, myself, personally intend to continue being outspoken and opinionated, intolerant of all fanatics, fools and ignoramuses, deeply suspicious of all those who have "found the answer" and on my bad days, downright rude.
SloopJonB is offline  
Quote Quick Reply Share with Facebook
post #9 of 9 Old 03-11-2012 Thread Starter
Member
 
steveg353's Avatar
 
Join Date: Jun 2008
Location: Houston TX
Posts: 93
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
 
Re: If it's not luffing, it's helping?

I am just wondering if there is a point(dead into wind) when the main would hinder more than help. I am guessing, by what has been said, that if you must pull the sail past the centerline to stop luffing, it probably isn't helping power the boat forward or helping with fuel.
steveg353 is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
helping those who Bermudahigh General Discussion (sailing related) 0 10-22-2011 05:22 AM
Helping You In The Canaries Ecotec General Discussion (sailing related) 0 08-20-2010 08:58 AM
Rights and luffing sails jarcher Racing 13 08-25-2009 07:04 AM
luffing the leech ... mikehoyt Racing 10 08-11-2006 12:16 AM
Rules - Luffing v Sailing above proper course Bootydawg Racing 2 09-09-2005 07:15 AM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome