Tuesday, December 11, 2018

Actual Anchor Loads



I spent a LOT of time researching this topic, through the literature and by staring at a load cell for hours and hours. I used all sorts of rodes and snubbers, in all weather, on a number of boats.

ABYC (American Boat and Yacht Council) set standards for rodes and deck hardware 50 years ago, based on testing with boats on all-chain rode in open harbors and shallow water (but no breaking waves) and no snubber. In fact, these values are VERY close to what I got testing in similar conditions. This is very much a worst case situation and is something you should NEVER do, but is a good basis for the design of something that cannot fail. I don't think I've ever heard of a system meeting Table 1 requirements that was in good repair failing, outside the eye of a huricane (an even then it isn't the chain that breaks; they either drag or the roller and cleats fail.


Interestingly, every investigator reported 3-5 times less when they measured the strain on their boat (me too). Of course, they wisely anchored in deeper water (lower waves and more catenary), used rope, or used a snubber.

Looking only at the 60 knot row, which is very likely the most you will ever face without some protection from trees or shoreline, we see that the wind load is only about 20-25% of the ABYC load. Waves and snatching make up the rest. If you use a long chain in deep water (at least 20 feet), a long  snubber (35'-50'), or a rope rode, the load will be only 25-30% of the ABYC value.




For larger boats or those around coral and rocks, all chain is nice. Rig a LONG snubber, even if you have to cleat it at the mid-ships or stern cleats to keep the connection off the bottom.
My PDQ came with rope, but I changed to chain and a long snubber after a few years. I liked the increased security, but the main reason was that the windlass handled all-chain better than chain with a splice. 

In my mind, if your anchor is 35 pounds or more, you will be better served by a windlass and all chain, and if it is 15 pounds or less, manual handling and rope makes more sense. At 25 pounds, the decision is up to you, depending on pocketbook, fitness, and sensitivity to weight in the bow. I'd probably go with chain and a winch on a monohull or heavy cat, and manual with rope on a fast multihull.

 With smaller boats and mud bottoms, the rope is a better answer. It is much lighter, gives good shock absorption, and lasts as long or longer, if it is protected from chafe. You see, chain will fail from corrosion in 5-7 years, even if you don't anchor out, whereas nylon can go even longer if oversized a bit. So go oversize for durability and ease of handling. Finally, nylon can actually be too stretchy if over 100 feet are out, and oversize rope reduces this.
My 24-foot, 1700-pound trimaran only calls for 3/8-inch nylon rode, but I like 1/2-inch for better handling, durability, and reduced stretch. I did the same on my Stiletto 27.

I've even gone to a Dyneema bridle to reduce yawing and to reduce the sometimes-excessive stretch of all-nylon rode. Because the bridle does not distort under shifting loads, yawing is reduced.

[Images excerpted from Rigging Modern Anchors.]

Monday, November 26, 2018

Northill Anchors

It seems quite a few have never heard of these, so I thought I would post a few images. I used one a bit with my Stiletto 27; it was better than Fortress in weed, rocks, and shell, and the new generation anchors had not taken off yet. I used it a little with my PDQ 32, testing in-line rigs, but never collected hard numbers; there did not seem much point, as they are long out of production. But I'm thinking of going back to it for my F-24, since it has a few advantages:
  • Folds flat
  • Very easy to assemble, better than any other break-down anchor (less than 10 seconds)
  • Works on any bottom type
  • Good reset behavior
  • Good holding capacity (450 pounds for 12-pound 6R Utility in mud), comparable to  many new generation anchors. The cross stock adds a LOT of holding power when it meets the bottom. I've tested this anchor to 750 pounds in fine sand and it didn't budge.
It has one disadvantage:
  • The lazy fluke is sticking up. A problem if the tide does a 360, which it can.
I still have the one shown below, and I think it is the right size for the F-24. All you do to fold it is unclip a carabiner and slide the stock out.

Northill 6R, 12 pounds.


They suggest a larger anchor, at least a 12R for a storm anchor for the F-24, but I carry a second anchor and I'm pretty good at reducing the load. And really, I'm just day sailing, anyway. If I start cruising, I'll find a nice cove for nights.

Sunday, November 25, 2018

The Tradition of Tandem Anchors

I have never liked tandem anchors, because with a change in direction, the lead anchor always rolls out and becomes pinned on its back, a position from which it often cannot recover. All of the manufacturers, other than Rocna, agree. So how did the idea become popularized?



Some time ago I was reading a 1930s sailing book, pre-CQR and pre-Danforth, and they showed a tandem anchor set up. They liked it for mud, not rocks. And their reasoning made perfect sense for the time, because...

  • The anchors were both traditional fisherman style. There was no back to roll over onto. If it rolls, it is ready to dig again.
  • A fisherman is poor in mud but good in rocks.
  • A fisherman doesn't really bury well, so the negative impact of secondary rode tension is small.
  • V-arrangements are fatal with fisherman's anchors; you will foul for sure. So this is the only logical 2-anchor rig.

So in-line tandems were traditionally used with fisherman's- or yachtsman's-style anchors... but are wrong with today's less symmetrical anchors. 
I wonder if it would work with twin Northills? I'm temped to get another one, just to see. I'll have to watch E-Bay, just because I like to expereiment.


Tuesday, November 20, 2018

Why does the World Sailing Off-Shore Rule Forbid Wider Pulpits?

It can be awfully skinny at the bow. The obvious solution is to set the railings outside, a little wider:

I would like to see a beefy toe rail with this arrangement, required by the Off-Shore Rule. The rule also requires a mid-rail. Net is not required, but it would finish the job.

 The front curve is handy for suporting the bowsprit when foldedI like that the F-24 has a place to attach a safety line at the back corner. It reduces sail snagging and guards a gap.



But the Off-Shore Rule is rather specific:


 Not only does this make for a safer work area, it avoids jib impingement.


I'm confused. It seems like a good idea to me. I understand why this would be important farther aft, since rail meat would be sitting farther aft. but that is a different matter and easily excluded, if that is the intention.

Thursday, November 15, 2018

Hugo Boss Sets a Record, Over 38 Knots

On the other hand, I love my Farrier. I bet my dollar-to-grin ratio is higher. It better be, since I don't have the dollars.


Wednesday, October 31, 2018

Man, We're Getting Old... and It's Getting Worse

(From a 2016 boating trade presentation on the state of the industry)

The conclusion of industry analysts is while new boaters come and go, the core of long-term sailors is stable. Those of us that become addicted occasionally sell a boat, but then by replacement. That's certainly my story, having owned a beach catamaran, Stiletto 27, PDQ 32, and now a Corsair F-24 Mk II.

Unfortunately, new boat owners come, but mostly go. As a result, boating is in gradual decline. Some point to New Age alternatives--the internet and other sports. Some correctly point out chartering is on the rise--boat ownership and all of the maintenance that goes with it is a good fit with the new generation.

Small boats are still a healthy industry. My daughter, for example, would love a sailing dinghy and I'll bet she'll buy one someday. But you can't see her owning a bigger boat. It wouldn't fit her needs, and the maintenance and fiddling would never hold her attention. I can see that. It feels pretty irrational at times to me.

The result is that we sailors are getting older and older. It doesn't just seem that way, it's true. I'm okay with that. By the time the sail population ages enough that my target market has evaporated, I'll have run out of things to write about.

Bow Wind Indicators

Masthead wind indicators are ubiquitous. Unfortunately, they can be hidden by sails, put a crick in your  neck, and take your eyes away from where you are going.

 The highlight vane is enlarged 2x.

On beach cats, a vine under the bridle is common. It's right in your line of sight when the action gets fast and allows you to watch the lee bow, as it tries to turn submarine.

I've always had vanes on the bow. The crew like them both for sailing, and just as much for hoisting sail and anchoring; they arn't all sailors and they don't like looking up while driving forward. They have a point. It can be tricky to locate them so that they are not damaged. In this case, the pulpit and the bow sprit up-haul line (blue) have kept them safe.


Why two vanes? I have been testing vanes for 2 seasons for an up coming article, rotating models from time to time. There is nothing like time-in-service to sift out the top performers.

 You would think the air would be more disturbed by sails. but in fact they reflect only a slight curving of he wind near the sail.

The Bottom Line. I like them all. I find them handy on every point of the sail, but perhaps most useful tacking and jibing. Look for the Write-up in Practical Sailor Magazine.

Monday, October 29, 2018

Trimaran Bridle

Multihulls love bridles, but going out on the skinny amas of a trimaran to rig that bridle is uninviting if there is any chop. Thus, I leave mine rigged but retracted.

 The line is over-size Dyneema; about 15x maximum working load, including allowance for single leg loading. The normal load factor for Dyneema would be about 4x, so this allows me to loose 75% strength to UV and wear before reaching the WLL. That should take over 10 years, based on available desert testing. This also squares with my personal experience with old Dyneema.

 When not in use, they are pulled back to mid-tramp by a Davis Instruments Mini-Shockle (a very heavy duty bungee). The front end is secured to the pulpit with a carabiner.


 To deploy, the Shockles are released and the carbiners are clipped to a prusik sling.

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To learn more about anchoring with rope, visit Practical Sailor Magazine. This last image is from and up-coming series on anchoring without chain.

Friday, October 26, 2018

No-Discharge Zones

In 2017 a new No-Discharge Zone (NDZ) was established in the Puget Sound. In stead of allowing discharge of treated wastes 3 miles from shore now there will be none. The local cruisers feel they have been demonized, but in reality it is the cruise ships that were targeted.

The Puget sound is unique in that it is the ONLY large bay where the 3-mile rule applied. All other bays (Chesapeake, San Fransisco, etc.) are considered inland waters, and all discharge of untreated waste is banned, whether 3 miles from shore or not. But the Puget sound is shared with Canada and is thus not the inland waters of the US.

Because the navigable waters are regulated by the federal government, the state has no authority to regulate discharges from boats, OTHER than requesting NDZ status from the EPA, which is quite easy, so the Washington state EPA had only one option; NDZ status.

NDZs began with the Clean Water Act (CWA) in 1972. They are often seen as political statements.


I'm not seeing a correlation with presidential party affiliations. There was a predictable burst when the law passed, no interest nearly a decade, and then a pretty steady rate since. The last Bush administration implemented 4 more NDZs than the Obama administration. If there are politics, they are local in nature and consistent.

Perhaps the rate is now declining, as the map gets filled in.

Interestingly, the Friends of the Earth petitioned the EPA in 2010 to allow several popular high-efficiency treatment systems, arguing they were better for the environment than a ban. How about them apples? It seems they believe that good treatment is better than the cheating that otherwise takes place. Rather like ethanol gas, the full cost of the regulation and the unintended consequences are not always considered. In this case, however, I think it is more a matter of the convoluted nature of regulations; the Washington EPA saw NDZ as the only available option.

Sadly, I don't think the effectiveness of treatment systems, such as the Rairitan Electroscan, is well understood.

Sunday, September 30, 2018

Helmets

After one more like wack on the head, and an invitation from a magazine to write an article, I fond myself pondering where on the safety scale helmets might fall. I'm think we are in the midst of a big change in mind set, akin to bicycle helmets in the 70s and 80s.

US Sailing has this to say [emphasis added]:


2015. A word of caution to all persons who consider using helmets while sailing. There is no data to confirm that helmets will prevent concussions. The brain injury comes from the acceleration/deceleration from the strike, which is apparently not substantially altered by a helmet.
Helmets have been shown to reduce the incidence and severity of facial and skull fractures, contusions and lacerations but not concussions. 

Concussions seem to occur more easily in pre-teen and teens. We also need to be aware that adding a helmet to a young head makes the head a “larger” target and could possibly lead to more head strikes.
Therefore, it is the position of the Sports Medicine Committee of US SAILING that helmets should be considered and encouraged but not mandated for:
♦ aggressive competitive sailing,
♦ crew positions at increased risk for strikes to the head, and
♦ sailors who are learning the sport and thus unfamiliar with the position and movement of rigging and equipment.

In the event that a concussion or head injury occurs, treatment and the evaluation for a return to activity should be done by a trained specialist. 

David Jones, M.D., Chair of the Sports Medicine Committee
Thomas Hubbell, M.D., President of US Sailing


Kayakers have long worn them. In fact, it is the law in many whitewater areas, including my home Potomac river from Great Falls to Chain Bridge. It's easy to get pasted in the head by a rock while inverted.

 The Protec Ace is top rated and economical. I like to for whitewater kayaking as well.

I googled ocean racing accidents. While head injuries represent only a small portion of the total carnage, they represent nearly half of the injuries resulting in evacuations or retirement. I strongly suspect they are a factor in some of the drownings ("So-and-so was knocked overboard by the boom [or spin pole, or banged across the deck] and was recovered drown.). You don't need a skull fracture to be dazed just enough to swallow some water after going in head first.


A little impractical, I think. For a helmet to prevent concussions it needs to be thick enough to provide deceleration distance.All kidding a aside, the risk of entanglement in lines and increased impact when hitting the water at speed disqualify and oversized design.

I googled cruisers. There's a good list of injuries in heavy weather. I've been tapped a good number of times, but a cap is enough for those. I did get swatted to the deck once, but it was just a skimming across the crown and did no damage. But it makes you think.

And then there is the danger of the helmet itself. I wide rim, like a bike helmet could snag on ropes. A brim could add to rotation or catch on the water at high speed. A helmet needs to be compact, such those we are seeing on many performance boat crews. I need to feel the wind. It cannot block my vision. On the other hand, it could keep my head warmer in the winter and it could double as a rain hat. Which brings up the matter of interference with the hood.

As I descend the rabbit hole of article research, I'm becoming convinced they are rational in many settings. Youth through college sailing, beach cats and skiffs, and maybe any small boat racing where mark rounding get crazy. Ocean racing in rough weather. Up the mast off-shore for everyone.

But what about cruising scenarios?  The foredeck when it's bad. Perhaps it is like headlights (if the wipers are on, the head lights must be on); if tethers are needed, so is a helmet? No, that seems like too much as a general rule. On the other hand, seatbelts don't seem very useful until that one instant you need one. When I look at the numbers, including only experiences sailors, It's hard not to see PFD, tethers, and helmets in a similar light. The accident numbers say they are all in the same range. Discomfort and expense are all in a similar range, I think. You wear a hat and I'm pretty used to my bike helmet. But I do miss the wind in my hair and I don't always wear it.

Food for thought.