Is there any safety issues with boats not having backstays?

DAP007

.
Feb 16, 2023
1
Hunter 23 Deltaville
I have a Hunter 23, which has a backstay. I found out my friend who has a Hunter 23.5 does not have a backstay. I feel safer knowing my mast has the backstay and feel it would help prevent demasting more than a boat not haveing a backstay. Does anyone have any literature for or against that self-made theory?
 
Jan 11, 2014
12,648
Sabre 362 113 Fair Haven, NY
Welcome to SBO.

Some rigs are designed to have a back stay, some not. Hunter used a B & R rig on a number of their boats which does not have a backstay. The rig has swept back spreaders which counter the load from the forestay. The advantage to this rig is a larger roach on the mainsail which provides more power. The downside is the mainsail can not be let out as far when heading downwind.

The really short story is, if the rig was designed to have a back stay, it needs a back stay. Although, in terms of keeping the mast up right it is the least important of the 4 main stays, forestay, cap shrouds (uppers) and back stay.
 
May 17, 2004
5,532
Beneteau Oceanis 37 Havre de Grace
All other things being equal you’re right that a backstay would be necessary to effectively hold up the mast. The thing is that all things aren’t equal between the rig designs. The backstay-less rigs have significantly more swept spreaders, so the upper shrouds are providing all of the aft pull on the mast that the backstay otherwise would. In terms of net force they can both be built to provide equivalent strength. Whether or not they are in practice is a matter of implementation, but that doesn’t make the design inherently worse.

Personally I’m not a fan of backstay-less rigs because the spreader sweep also reduces freedom to trim the main on a run, but that’s more personal preference than an absolute.

To flip the coin on the strength argument - consider that failure of any shroud or the forestay or backstay on a traditional rig means possible dismasting, but a backstay-less rig has one less point of failure.
 
Jan 11, 2014
12,648
Sabre 362 113 Fair Haven, NY
Rig loads are pretty dynamic and there is some inherent redundancy for the forestay and backstay with the jib luff absorbing some of the forestay load and the mainsail leech and sheet absorbing some of the load from the backstay. The most critical stay is the windward cap shroud, if this should fail the mast or part of the mast will come down.
 
Sep 25, 2008
7,332
Alden 50 Sarasota, Florida
It’s been a while since we owned a H40.5 but it had a backstay and the spreaders were swept back as in a B&Rdesign. Guess it was some hybrid of conventional and B&R.
 

Joe

.
Jun 1, 2004
8,149
Catalina 27 Mission Bay, San Diego
I have a Hunter 23, which has a backstay. I found out my friend who has a Hunter 23.5 does not have a backstay. I feel safer knowing my mast has the backstay and feel it would help prevent demasting more than a boat not haveing a backstay. Does anyone have any literature for or against that self-made theory?
You will learn over time than many boat designs do not have "backstays" per se. The mast is supported in other ways. Almost all small sailing vessels... catamarans, dinghies, etc. are not designed with backstays. Catamarans in particular because their twin hull geometry, coupled with a mainsail that has large roach (the curved area of the sail beyond a straight line from top to back corner). That's also why you will see full length battens sewn into their mainsail..... to support the extra roach area... a backstay would interfere with the sails battens when it goes from side to side.
You'll no see backstays in most racing dinghies.... under 18 ft for sure... for the same reason, large mainsails and relatively short hull length,
Boats that don't have the traditional backstays you imagine, support their masts with a forward stay going to the pointy end of the hull, and two swept back shrouds (sometimes referred to as "side stays"). These 3 stays create a triangular support.... just like a large radio antenna. Each stay will be adjustable to optimize performance.

My Nacra 5.2 (17ft beach cat) is typical. A forestay and two swept back shrouds. The traditional backstay's rig adjustment features allow the crew to control aspects of the mast and thus affect the trim of headsail and mainsail. With out a backstay, sailors control mast bend and forestay tension (which in turn affects mainsail and headsail shape/trim) by using other tools. A powerful cunningham, for instance, not only tensions mainsail luff tension, but is strong enough to actually impart mast bend. Beach cats and other small backstay-less boats will have extra powerful mainsheet tackle... which can also help bend the mast via the mainsail's leech (trailing edge). The boom vang can provide additional trim options not needed with a backstay equipped.

Therefore, young sailor, a boat with no backstay is nothing to fear....unless of course, it's supposed to have one. In that case, someone has goofed.
So.... quit you're fretting. What you should actually be concerned with is what to do if your boat's backstay breaks!!!! You really need to know that before you take your boat out again. I challenge you to answer that question. "What if the boat's backstay breaks? How do I prevent losing the mast?" Pop quiz tomorrow, do your homework, don't wait for someone else to give the answer. good luck, have fun.
 
Jan 1, 2006
7,452
Slickcraft 26 Sailfish
Great pic of the trimaran, Thinwater! I note how close the main comes to being the shape of an airplane wing. Doesn't need no stinking' backstay!
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,691
CAL 35 Cruiser #21 moored EVERETT WA
I have sailed Dinghies and small sailboats without back stays. Each was safe and secure. I now sail boat with a back stay. It also feels safe and secure.

Different boat designs require different systems.
 
Jan 19, 2010
12,549
Hobie 16 & Rhodes 22 Skeeter Charleston
Personally I’m not a fan of backstay-less rigs because the spreader sweep also reduces freedom to trim the main on a run, but that’s more personal preference than an absolute.
This is true-ish... but you also have a larger main facing the wind on a run because of the larger roach. Personally, I liked the trade-offs of the B&R. The only time I missed having a back stay is when I wanted to fly a flag off of the back of my boat. I used the topping lift instead ....

On my H26, I felt the real limiting variable on a run was the relatively small fractional jib.... but the H26 came with a spinnaker halyard so it could be set up better.
 
Jun 8, 2004
10,373
-na -NA Anywhere USA
@DAP007

I am a retired Hunter dealer who introduced the 23.5 with no backstay having sold nearly a quarter of the production line. I do not know of any mast failures due to the B & R rig. I replaced masts on the 23.5 due to ignorance, lack of maintenance/tuning, lack of knowledge and so forth. I know my boat all too well. The original plans for the 23.5 came from me given to Hunter.
 
Jul 12, 2011
1,165
Leopard 40 Jupiter, Florida
The B&R rig discussed above is standard on all production catamarans. Think about the huge number of large cruising cats that are in (rough) charter service, have crossed oceans, circumnavigated, and done other feats. I live on one of these, and have minimal concerns of dismasting due to only five (largish) steel cables. When you sit on a three-legged stool, you don't wonder if you are unsafe because of the "missing" leg. It's all how they are designed.
 
Jan 7, 2011
5,414
Oday 322 East Chicago, IN
My Hunter 280 had the B&R rig with no backstay. It was designed to not need a backstay. Never had an issue with it.

But my O’Day 322 is a masthead sloop, with a back stay. Yes, I feel better with the backstay.

But many Hunter B&R boats out there for many years.


And consider a Freedom sailboat that has no stays or shrouds…

All depends on how the boat was designed.


Greg
 
Mar 13, 2011
82
Seaward Fox 19 Lakeview, Ohio
We had a 23.5 and there were no issues! Loved the mast raising system in the 23.5. The water ballast was a bit of a pain, but wish we had her back at this point. Our watershed group and the introduction of zebra mussels cleared our shallow lake so well, we now have a "salad sea". But no back stay, never an issue even in rough winds.