Film ****** Assistance - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > General Interest > General Discussion (sailing related)
 Not a Member? 


Reply
 
LinkBack Thread Tools
  #1  
Old 03-07-2012
Junior Member
 
Join Date: Mar 2012
Posts: 4
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
John Merrick is on a distinguished road
Film ****** Assistance

Hello there,

I would be very grateful if anyone can spare the time to answer two questions. I apologise in advance for the ignorance I will inevitably display - I am far from seaworthy!

1: If a sailboat becomes unmanned, with its sails fully hoisted, and with a strong wind at its back, what is the likely pattern it will describe?

2: I realise the above is dependent on a great many factors, so a further question would be - how would the unmanned boat need to be rigged for it to continue to travel unmanned with speed, however erratically, and what wind conditions would ensure this?

Any answers will be much appreciated, thanks!
John
Reply With Quote Share with Facebook
  #2  
Old 03-07-2012
AllThumbs's Avatar
midlife crisis member
 
Join Date: Jul 2008
Posts: 967
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 7
AllThumbs is on a distinguished road
Re: Film ****** Assistance

It depends but downwind a sailboat would likely continue on it's course or close to it after the sailor fell off.

I would say the "best" way to ensure this at least for a time is to have the boat sailing "Wing and wing" (main and foresail flying on opposite sides of the mast with boat going directly downwind)

or, foresail only, no main.

Eric
Reply With Quote Share with Facebook
  #3  
Old 03-07-2012
deniseO30's Avatar
Move over Joan Rivers!
 
Join Date: Nov 2006
Location: Bristol pa
Posts: 5,982
Thanks: 51
Thanked 82 Times in 72 Posts
Rep Power: 9
deniseO30 will become famous soon enough deniseO30 will become famous soon enough
Re: Film ****** Assistance

Welcome to Sailnet!
Others can explain it better then me but, If the wheel or tiller isn't locked or on auto pilot. the boat will round up into the wind. depending on the blow it will wander at the mercy of the wind and current. The boom will slam side to side, boat may heel over.

Wind at the back is the most difficult to maintain course. Sailboats are like weather vanes but will be all over the place without steerage.
__________________
Denise, Bristol PA, Oday 30. On Tidal Delaware River, Anchor Yacht Club. New Website!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

my current "project"!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #4  
Old 03-07-2012
FSMike's Avatar
Senior Member
 
Join Date: Jan 2010
Location: Florida
Posts: 580
Thanks: 0
Thanked 13 Times in 13 Posts
Rep Power: 5
FSMike is on a distinguished road
Re: Film ****** Assistance

John -
Too many variables for a truly accurate answer, but:
In your first case scenario the boat will probably describe wide variations in course, but will probably end up going in a downwind direction overall.
In the second scenario, having only a jib up will probably have the boat proceeding in a generally downwind direction due to the center of effort of the sails being towards the bow.
If there is some sort of self steering device rigged the boat could go in most directions, depending on which sails are used and how the self steering is rigged.
If you're trying to film an unmanned boat under sail, put somebody below decks with the remote controls for the autopilot.
__________________
Sail Fast Live Slow
40' Norman Cross trimaran

Last edited by FSMike; 03-07-2012 at 11:23 AM.
Reply With Quote Share with Facebook
  #5  
Old 03-07-2012
Junior Member
 
Join Date: Mar 2012
Posts: 4
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
John Merrick is on a distinguished road
Re: Film ****** Assistance

Very helpful answers, Eric, Denise and Mike, and fast too! That's all I really need for now, but I think I'll have to return here when things get more specific.

Thanks again,
John
Reply With Quote Share with Facebook
  #6  
Old 03-07-2012
Senior Member
 
Join Date: Jun 2005
Location: New Orleans
Posts: 1,860
Thanks: 6
Thanked 23 Times in 21 Posts
Rep Power: 10
nolatom will become famous soon enough
Re: Film ****** Assistance

you're probably describing a broad reach with the wind behind but not directly behind, and if sailing some distance, likely with an autopilot steering the boat.

Fall overboard then, and the boat will keep sailing away on a broad reach.

No autopilot? then she'll round up to a reach, luff and spill most of the wind but not all, and make slow progress downwind as long as there's wind and searoom, until after a couple of months the sails start to tear and shred from all that luffing.

That help?
Reply With Quote Share with Facebook
  #7  
Old 03-07-2012
KIVALO's Avatar
Senior Member
 
Join Date: Nov 2011
Location: Central New York
Posts: 391
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 3
KIVALO is on a distinguished road
Re: Film ****** Assistance

For what its worth I snapped my rudder off, that's sort of like the skipper falling overboard, and the boat rounded up and tacked but by then I had loosed the sails we drifted until I was able to lower the sails.

Brad
s/v KIVALO
__________________
s/v KIVALO
2003 Hunter 260
"Any damn fool can navigate the world sober. It takes a really good sailor to do it drunk." - Sir Francis Chichester while loading his boat with gin.
WORK IS OVER-RATED
Reply With Quote Share with Facebook
  #8  
Old 03-07-2012
Junior Member
 
Join Date: Mar 2012
Posts: 4
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
John Merrick is on a distinguished road
Re: Film ****** Assistance

Quote:
Originally Posted by nolatom View Post
you're probably describing a broad reach with the wind behind but not directly behind, and if sailing some distance, likely with an autopilot steering the boat.

Fall overboard then, and the boat will keep sailing away on a broad reach.

No autopilot? then she'll round up to a reach, luff and spill most of the wind but not all, and make slow progress downwind as long as there's wind and searoom, until after a couple of months the sails start to tear and shred from all that luffing.

That help?
That did help, thanks. In fact, I do have another, more specific question to the film.

If you were to fall overboard whilst the boat was stalled, and a strong downwind suddenly picked up, would the boat's acceleration be quick enough to preclude you getting back on board? I had presumed yes, but it would be nice to know more definitively.
Reply With Quote Share with Facebook
  #9  
Old 03-07-2012
Senior Member
 
Join Date: Jun 2005
Location: New Orleans
Posts: 1,860
Thanks: 6
Thanked 23 Times in 21 Posts
Rep Power: 10
nolatom will become famous soon enough
Re: Film ****** Assistance

Quote:
Originally Posted by John Merrick View Post
That did help, thanks. In fact, I do have another, more specific question to the film.

If you were to fall overboard whilst the boat was stalled, and a strong downwind suddenly picked up, would the boat's acceleration be quick enough to preclude you getting back on board? I had presumed yes, but it would be nice to know more definitively.

If by stalled you mean stopped or drifting very slowly due to calm wind, then yes, wind resumes at say 10 knots, boat is on autopilot (or maybe even not) and begins to sail downwind at say 3 knots. Most average swimmers max out around 2 knots and can't sustain that for too long, so do the math...

But the boat would accelerate slowly, might take a half to a minute to reach that speed. So kind of a coin-toss whether Mr. Oscar Overboard could reach her before she got up to speed, depending on his distance off, was he injured in the fall, what's the water temp (hypothermia etc).

But a big factor is even if her could get to the boat, could he get back on board? Most offshore cruisers are quite high-sided, and if he hasn't left a ladder out, or a line trailing astern, your character could be plumb out of luck.
Reply With Quote Share with Facebook
  #10  
Old 03-07-2012
Junior Member
 
Join Date: Mar 2012
Posts: 4
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
John Merrick is on a distinguished road
Re: Film ****** Assistance

Quote:
Originally Posted by nolatom View Post
If by stalled you mean stopped or drifting very slowly due to calm wind, then yes, wind resumes at say 10 knots, boat is on autopilot (or maybe even not) and begins to sail downwind at say 3 knots. Most average swimmers max out around 2 knots and can't sustain that for too long, so do the math...

But the boat would accelerate slowly, might take a half to a minute to reach that speed. So kind of a coin-toss whether Mr. Oscar Overboard could reach her before she got up to speed, depending on his distance off, was he injured in the fall, what's the water temp (hypothermia etc).

But a big factor is even if her could get to the boat, could he get back on board? Most offshore cruisers are quite high-sided, and if he hasn't left a ladder out, or a line trailing astern, your character could be plumb out of luck.
Again, very helpful, thanks. Especially the half to a minute acceleration factor.
Reply With Quote Share with Facebook
Reply

Tags
film


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Seaclear assistance needed bhcva Gear & Maintenance 8 08-21-2007 11:32 PM
Assistance with interior fabric wheeltime General Discussion (sailing related) 2 07-31-2007 06:59 PM
Big Navy to Assistance of S/V Chaunclm Cruising & Liveaboard Forum 25 06-05-2007 03:56 PM
biologists looking for assistance teambenthos General Discussion (sailing related) 12 06-01-2004 12:59 PM


All times are GMT -4. The time now is 12:42 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.