Masthead, or Fractional Sloop?

Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Now for a simple question. I 1994 Hunter 40.5, standard sized battened main, non furling, solid foot, overlapping Genoa (not sure of how much, probably 130%). From what I'm reading if I intend to do a lot of beating to windward, I'd be better off with a non-overlapping Jib, Is that correct?
Not unless you typically sail in 15 knots plus. Otherwise, just like most boats, you're best off with a headsail sized for your typical winds. If your boat powers up with that 130, use that.

Remember, boats that use non-overlapping headsails were DESIGNED for that, and will have taller masts and more area with just the jib.
 
May 1, 2011
4,238
Pearson 37 Lusby MD
Do I race? Not formally but you bet, when I am on a near parallel course with a sailboat of approximately the same length as mine I'm always thinking, "I'm gaining on him" or "he's going faster than me, I need to adjust the sails." Be honest, don't you do that too?
That's the two boats, it's a race department. I absolutely do that!
 

Kermit

.
Jul 31, 2010
5,657
AquaCat 12.5 17342 Wateree Lake, SC
Should I take my sister-in-law and brother-in-law sailing New Year’s Day? We have a fractional sloop with a B&R rig and roller furling. My head is swimming.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
If I'm designing my own boat, its rig will be based, in part, on what I learn here.
I'm going to go lookup performance data on the delta rig now. I think it might be pertinent. Be back to report.
There have been several variations on the aft-mast design, the delta being one of them. The common denominator is how any of them sailed.... quirky.

Oh. and forget spinnakers.
 
Oct 19, 2017
7,744
O'Day 19 Littleton, NH
My head is swimming.
Isn't that normal for you?

aft-mast design, the delta being one of them. The common denominator is how any of them sailed.... quirky.
http://www.transitionrig.com/delta_sails.htm

An article on the crab claw rig:
http://proafile.com/multihull-boats/article/proa-rig-options-crab-claw

"with the heading angle 90 degrees, the driving force coefficient of the crab claw is about 1.7, whereas that of the Bermuda rig is about 0.9. That is, the crab claw rig delivers about 90% more driving power than the Bermuda rig."

Apparently, these results have not been reproducible.
- Will (Dragonfly)
 
Oct 19, 2017
7,744
O'Day 19 Littleton, NH
Anyhow, it doesn't matter at this point. Your statement about new fractional rigs is still a good one.:thumbup:
- Will (Dragonfly)
 
Nov 30, 2015
1,337
Hunter 1978 H30 Cherubini, Treman Marina, Ithaca, NY
Masthead rigged, hanked on 110, also have a 155 for light winds and don’t even need the main up with that on. The only fractional rigged boats I’ve sailed are all little day sailers. What’s this fuss over anyway. I’ve got this old girl up to 8.5 (THS 5.5 kts) on a broad reach and 7.0 kts into the wind on a 22 degree heel in 15-20 Knot breeze. All boats I’ve chartered in the BVI are mast head rigged.
Wanna race in this class heavy weight...I’m game next season.

D42B3E47-F3E0-4027-BC9B-2A935D905AE2.jpeg
 
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walt

.
Jun 1, 2007
3,511
Macgregor 26S Hobie TI Ridgway Colorado
As I believe already mentioned, the benefit of the fractional rid is being able to tune the main sail shape by bending the mast. It seems odd that you can actually do that on say a 60 foot boat with a 7/8 fractional rig.. must be some serious tension on that backstay! But I can definitely bend the mast on my old fractional rig 1990 Mac 26S with the backstay.

A video earlier said less backstay tension for light wind or downwind and more backstay tension for heavier wind. More or less are relative so what indicators do you use to tune the backstay?

Not really knowing what Im doing, I have been watching the tell tail on the windward side of the main just aft of the mast and about 3/4 the way up the sail. It seems I can often get rid of a separation bubble on the windward side by adjusting the backstay tension. It also seems that I will get an "S" shape behind the mast in higher winds that should not be there and I can get rid of that with higher backstay tension.. My main is getting somewhat past its prime now so those could be just that I need to replace the main.. wont know until I get the next one.
 
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May 17, 2004
5,071
Beneteau Oceanis 37 Havre de Grace
Not really knowing what Im doing, I have been watching the tell tail on the windward side of the main just aft of the mast and about 3/4 the way up the sail. It seems I can often get rid of a separation bubble on the windward side by adjusting the tension. It also seems that in higher winds, I will get an "S" shape behind the mast in higher winds that should not be there and I can get rid of that with higher backstay tension.. My main is getting somewhat past its prime now so those could be just that I need to replace the main.. wont know until I get the next one.
In general for the main the leech telltales are the more valuable indicator than ones close to the luff. The luff is affected by turbulence off the mast and so may not be showing you what’s really going on. As you add backstay tension you might just be removing some belly, putting that telltale someplace the turbulence doesn’t affect. I guess it’s also possible that if the sail is old and blown out, and adding the tension compensates for that a bit.

In higher winds the wind pressure might be adding more draft to the sail, and certainly as the wind speed goes up you’ll want the extra backstay tension to flatten the sail and depower it. Depending on the wind speed a bit of S shape might be ok anyway, further depowering the sail and keeping the boat on its feet.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Backstay has little effect on ‘trim’. Use backstay to flatten the mainsail, which will help keep the boat flat. So that’s your gauge. Boatspeed and heel, not trim.
 
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Ted

.
Jan 26, 2005
1,254
C&C 110 Bay Shore, Long Island, NY
Downwind, masthead rigs used to do better against fract spin boats because they where fractional spin hoist as well, because old (IRC and PHRF) rules dumbly penalized them for a hoist bigger than J.
Being penalized for a hoist bigger than "J" would be really dumb, even for IRC and PHRF. :rolleyes: I'm sure you meant "I".

On my last masthead boat I had a baby stay. Although it made fast tacking with a large genoa a bit challenging without someone forward of the mast to help it around, it was good in other respects. You are able to bend the mast independently of forestay/backstay tension making main and headsail trim less dependent on each other which allows for more sail shape options.
 
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Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Being penalized for a hoist bigger than "J" would be really dumb, even for IRC and PHRF. :rolleyes: I'm sure you meant "I".

On my last masthead boat I had a baby stay. Although it made fast tacking with a large genoa a bit challenging without someone forward of the mast to help it around, it was good in other respects. You are able to bend the mast independently of forestay/backstay tension making main and headsail trim less dependent on each other which allows for more sail shape options.
LOL for sure ‘I’! ;-)

C&C was the best at getting the most out of a masthead rig.