Eric's Dream Job

(poached the photo from here http://www.blueoceantackle.com/anchors_and_chains.htm )

That's a monster indeed and the ship it's attached to is probably a monster also. I wonder how this would stack up in a weight of anchor to weight of vessel relationship. When seen on ships they look so small. But larger pleasure craft seem to visually have smaller anchors also. If I was to find out that ships have anchors that would equate to an very small anchor on my boat I'd wonder how they could hold the boat.

I saw this yacht in Craig AK a few years ago and it looks like it's Navy anchor gets used. If newer anchors are so much better why does this very valuable yacht depend on an anchor we all think it has so little holding power it's practically useless? It has a very important job and I'm inclined to think the people that put it there probably know what the're doing. Actually it could have been "put there" by the NA that designed the boat as the recession in the hull that the anchor resides in looks much like the other recessions on the sides of the hull. For boats this size there is probably a maritime standard (perhaps insurance related) that specifies the size of numerous types of anchors similar to the Navy anchor. Manson makes anchors for boats like this that look much like this Navy anchor. They call them a "Kedge" and the smallest is 112lbs. I saw on a website another company offering Navy anchors as small as 100lbs.

What do you think? 4 to 1, Anchor vs. Willy? Probably not big enough.

manyboats said:

For boats this size there is probably a maritime standard (perhaps insurance related) that specifies the size of numerous types of anchors similar to the Navy anchor.

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http://www.iacs.org.uk/vdunifiedrequirements/ur_a_pdf148.pdf

Rick I made that comment hoping you'd respond. Haven't figured it out yet. What is "EN"? And what are "Bower" anchors?

manyboats said:

That's a monster indeed and the ship it's attached to is probably a monster also. I wonder how this would stack up in a weight of anchor to weight of vessel relationship. When seen on ships they look so small. But larger pleasure craft seem to visually have smaller anchors also. If I was to find out that ships have anchors that would equate to an very small anchor on my boat I'd wonder how they could hold the boat.

I saw this yacht in Craig AK a few years ago and it looks like it's Navy anchor gets used. If newer anchors are so much better why does this very valuable yacht depend on an anchor we all think it has so little holding power it's practically useless? It has a very important job and I'm inclined to think the people that put it there probably know what the're doing. Actually it could have been "put there" by the NA that designed the boat as the recession in the hull that the anchor resides in looks much like the other recessions on the sides of the hull. For boats this size there is probably a maritime standard (perhaps insurance related) that specifies the size of numerous types of anchors similar to the Navy anchor. Manson makes anchors for boats like this that look much like this Navy anchor. They call them a "Kedge" and the smallest is 112lbs. I saw on a website another company offering Navy anchors as small as 100lbs.

Click to expand...

One thing for sure is that that hawse fitting would not accommodate a Rocna. Okay, or a Sarca, or a Manson Supreme, etc.

Conrad,

Shouldn't take much creativity to solve that problem. Do you remember the way the Fortress was carried on that CG boat in the pic less than a week ago? As I recall it was basically a hawse pipe through the stem of the bow. And of course one could always use a small crane on the bow to lift the modern anchor up on deck. That's the way yachts did it before about 1955. That was one of the advantages of a Danforth or Kedge (Yachtsman's anchor). They could easily be stored on deck. Makes for a better looking yacht too. A modern hydraulic crane could lower the mast down on the deck when through putting the anchor in it's cradle. And of course a giant bow roller could easily be fabricated .... but the thing may get in the way of mooring or other operations. Lots of options.

manyboats said:

Rick I made that comment hoping you'd respond. Haven't figured it out yet. What is "EN"? And what are "Bower" anchors?

Click to expand...

I couldn't get the link to do anything....slow here today I guess, blowing 30NW and the internets are downwind......

EN is probably Equipment Number if that's a class document. The EN is a function of vessel size and windage and is used for sizing anchors, cables, etc.

Bower is just your largest anchor, classed ships will carry two of the same weight. Long ago the Best Bower was in the starboard hawsepipe, the Small Bower is in the Port hawsepipe, they are of the same size. Today they are just port and starboard bowers.

TAD .... Glad you're here. I'm trying to find out how many pounds of anchor is typically used to anchor how many tons of ship. We can all quickly compute that for our own boats and w the ships numbers we can learn or compare the difference between our boats and the same relationship of anchor to vessel weight of big ships.

I'm thinking their anchors must be small but only because they look small. And that dosn't make sense as we know the holding power of typical ships anchors is very low (comparatively) to our small boat anchors.

manyboats said:

TAD .... Glad you're here. I'm trying to find out how many pounds of anchor is typically used to anchor how many tons of ship. We can all quickly compute that for our own boats and w the ships numbers we can learn or compare the difference between our boats and the same relationship of anchor to vessel weight of big ships.

I'm thinking their anchors must be small but only because they look small. And that dosn't make sense as we know the holding power of typical ships anchors is very low (comparatively) to our small boat anchors.

Click to expand...

I guess it depends on whether you think a 40,000 pound anchor is small?

The comparison is possible, I can give you a spreadsheet to calculate EN, but you need a ship for which you have all the dimensions. And I don't think you'll find it useful. Proportionally you'll find ship's anchors are small, but their chains are huge. For instance, in the ABS rules for Motor Yachts, for an anchor of 200 LBS (You must carry two of these) the required chain is 85 fathoms of 1/2". That's 1400 pounds of chain times two, plus 400 pounds of anchors. These are the old style stockless ship's anchor, most class society's will let you reduce anchor weight (but not chain size) by 25% for a "modern" high-holding power anchor, this would be anything like a danforth, CQR, Bruce, Delta, Manson, etc.

Also note that ships often drag anchor in high winds, it's just not that big a deal because the bridge is supposed to be maned 24/7. When ship's are mothballed without crew it's always to mooring buoys and they drop their anchors, both of them.....

Thanks TAD,
Food for thought. Lots of variables like multiple anchors and extreme variations in weight for freighters.

I found Titanic's specs.
"water disp" 66000 tons. Anchors 4000 tons ea. = 6600-1 ratio.

My Willard,
Disp. 16000lbs. Anchor 18lbs. = 800-1 ratio.

So my gut feeling seems somewhat correct that 1lb of anchor on a ship has MUCH more weight to hold back.

If Willy had the same weight to hold as Titanic her anchor would weigh less than 3lbs .... IF i figured it correctly and I'm not great w numbers. Looks like my anchor is way too big.

Tried to find the anchor weight of an Alaska state ferry ... but failed. If I had better numbers better comparisons could be made.

My gift to you Eric...have fun

http://www.uscg.mil/d13/cfvs/acsa/ACSA_References/ABS3-5-1.pdf

Eric

For the Titanic numbers you posted, that works out to 17:1 or at 16,000 lbs for Willy a 940 pound anchor!

Where did you get a 4000 ton anchor? That seems pretty heavy.

Tad Roberts said:

Also note that ships often drag anchor in high winds, it's just not that big a deal because the bridge is supposed to be maned 24/7. When ship's are mothballed without crew it's always to mooring buoys and they drop their anchors, both of them.....

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No mooring buoys here at the fast-disappearing Suisun Bay reserve fleet.

Eric,

Here is some more anchor info for you.

Big E Statistics

Designation: USS Enterprise (CVN-65)
Keel Laid: February 4, 1958
Launched: September 24, 1960
Commissioned: November 25, 1961
Overall Length: 1,123'
Width (at widest point): 257'
Height (from keel to mast): 250'
Area of Flight Deck: 4.47 acres
Area of Hangar Bay: 216,000 sq. feet
Displacement: 93,000 tons fully-loaded
75,000 tons without airwing, jet fuel, or ordnance
Crew: 5,500 (airwing + ship's company)
3,500 (ship's company only)
Nuclear Reactors: Eight
Horsepower: 280,000
Top Speed: 30+ knots
Propellors: Four, each measures 18' diameter
Rudders: Four, each weighs 35 tons
Anchors: Two, each weighs 32 tons

Each anchor chain is 1,080 feet long, and consists of over 700 links of 369 pounds each. Each anchor chain weighs 113 tons.

The Displacement/Anchor ratio is 2906:1.

For your Willie, using the same ratio, you would need an anchor of only 5.5 lb. . . . . . .

The scaling is obviously not linear.

Cheers

MurrayM said:

(poached the photo from here Anchors and chains and marine equipment. )

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Blue Ocean Tackle is a great site! I see they also are offering the Black Pearl for sale Pirate Ship For Sale

Murray,
Yes it's a can of worms and TAD hinted of that in a previous post.

EN??? I think I'll just leave that one lie. Bower? Yet another name for an anchor.

Tom I got the 4000 ton anchor number from the Google Search anchor images. One thumbnail gave some specs for Titanic. She was rather large .. Right? Over 1000' long.

Mark I remember seeing those old ships when I was 19. Three of us in a 1940 Chevy coupe. First time to California. Still remember the very warm sun and huge palm trees. Had our first frost last night.

Larry,
Great old stuff. I think the Titanic's rudder was 116 tons. Still wasn't enough rudder when they needed it. It was made of multiple pieces.
5.5lbs EH? Well that's more than I figured.
1961 .... That's when I joined the Navy. The Big E was the star of the fleet then.
Not linear? You mean I don't get a 32 ton Bower? Or do you mean the ratio should be much the same for ships AND boats. Well maybe there's more of those guys say'in their anchor isn't big enough until their friends are making fun of their huge anchor. We even had a thread "Bigger is Better" or someth'in like that. If you adhere to the philosophy of "get the next size up" theory one may be inclined to do that twice or start w a blown up number. Then get bigger yet. I started that w Willy. She came w a 13lb Danforth. I've used heavier anchors since then up to 35lbs. And I haven't dragged w any of them. I'm a firm believer in the philosophy of excess weight insures that machines will be less effective than they would be if they didn't have that excess weight. Now that I know my anchor only needs to be 6lbs maybe I should be scaling down instead of up from my 18lb Bower.

Well I think this has shown what I expected and I shouldn't be anchoring downwind of a big ship in a blow.

Thanks all for the help.

Eric,

That's for sure, in fact, just stay away from ships and their anchors!

anchor falls and hits tug boat bignellmatt - YouTube

manyboats said:

Thanks TAD,
Food for thought. Lots of variables like multiple anchors and extreme variations in weight for freighters.

I found Titanic's specs.
"water disp" 66000 tons. Anchors 4000 tons ea. = 6600-1 ratio.

My Willard,
Disp. 16000lbs. Anchor 18lbs. = 800-1 ratio.

So my gut feeling seems somewhat correct that 1lb of anchor on a ship has MUCH more weight to hold back.

If Willy had the same weight to hold as Titanic her anchor would weigh less than 3lbs .... IF i figured it correctly and I'm not great w numbers. Looks like my anchor is way too big.

Tried to find the anchor weight of an Alaska state ferry ... but failed. If I had better numbers better comparisons could be made.

Click to expand...

Which is why the E number takes windage as well as weight into account. Boats with the highest windage (sailboats with tall rigs and multi-story boxy powerboats) need bigger anchors and heavier/longer chain.....

Wman2blame

Just purchased a 175 lb. Mantus will let everyone know how it does, It's going to replace a50kg claw on a 54' trawler with 40 ton load. We will see what the deal is. We travel alot and I'm trying to worry less. I'm new to this site and just figuring out everything.Will post what the anchor lives up to.

Wman2blame

Just trying to see if pics show up on posts.

manyboats said:

My Willard,
Disp. 16000lbs. Anchor 18lbs. = 800-1 ratio.

Click to expand...

Does that actually work and keep you in place? Seems small....

Seaweed:
Weight 7000 pounds
Anchor 33 pound Rocna
Chain: 100' of 1/4" G4

And when I recover from the financial hit of the engine swap I'll buy another 150' of chain for the bow and move the 100' piece to the stern for my stop anchor (a 16 pound Hydro-bubble)

One thing I've had trouble with is figuring her displacement. I was on the .gov site for documentation and came away confused. Is there a trick to it that I've forgotten to determine displacement for my boat?

Thanks!

Janice aboard Seaweed, living the good life afloat
http://janice142.com

For weight ask the guy on the travelift next time you haul out and ask him. They have scales in at least most of them. Or seek out info from the manufacturer.

"keep me in place"? Always has. But when anchored in 50 knot winds both times I've was using a very unusual anchor .. that I trust. See pics. I use only small lengths of chain and 400' of nylon line. I also have a 13lb, 18lb and 35lb Danforth, a 22lb Claw, an 18lb Manson Supreme, and a 35lb Dreadnought. Used all but the 35lb Danforth. Most up to 35 knot winds. The anchors in the pics are XYZs. The one on gravel is older. I used it in one of the 50 knot gales. It was 13lbs. I sent it to the landfill when we moved south as it would not set in anything but soft mud. The other XYZ is not original. I modified it by putting a larger chisel shaped "nose" on it and it has set every one of the 10 (or so) times I used it on my trip south. See older post "Long Way Home" (there's two). Must have all been soft bottoms as I can't imagine it setting in anything else. In the future when it dosn't set I'll just put out another anchor. My 35lb Danforth is unusual too. Just acquired it recently. I think it was made by a salvage company. The only Danforth I've ever seen that looks strong enough. The shank and stock are 3/4" but it probably is just mild steel.

manyboats said:

For weight ask the guy on the travelift next time you haul out and ask him.

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It's been my experience that the TravelLifts don't give an accurate weight. During the last 3 haul outs I've asked the operator to give me the weight of my boat. In each case the reading was over 23,000 lbs and there is no way my boat weighs that much.

Well Walt it's been my experience that some TF members don't give an accurate account of political matters either. Re the oil thread. Hard to get good information these days.

I have no idea about the travel lifts as I've not inquired about Willy on the lift and I only know what the manufacturer and all the Willard owners say. Willy's heavy but it suites her. I assume they have scales on the travelifts so they won't pick up something too heavy for the lift so accuracy for lighter boats (most that the TL will handle) isn't necessary. The Port of Everett was right on re my Sumnercraft but that was just re the manufacturer's specs.
So you're probably right.

I once asked a travel lift operator how much Possum weighed. He gave me a number but said it wasn't very accurate. His lift didn't have a scale but he estimated the weight from the hydraulic pressure needed to lift her.

manyboats said:

"keep me in place"? Always has. But when anchored in 50 knot winds both times I've was using a very unusual anchor .. that I trust.

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That is an unusual anchor. I'm glad it successfully held you. So far I've not had to anchor in mud so I'm not certain how mine will work in those conditions. I'm hoping I don't have to experiment!

I do know that if I don't pull up anchor by day three I have to power out the Rocna -- with the old 25 pound plow it always came up with the windlass. I'm always at anchor so my perspective on anchors probably differs from the marina folks. Well, I did tie up to a dock back in January for a week (visiting friends) and then again I think it was in May for two days. Otherwise, on the hook works just fine for me.

Life is great afloat.

Janice aboard Seaweed
http://janice142.com

Don't know that boat Janice but she looks a bit heavy in the bow.
You should be aware that your boat with a high performance anchor like the Rocna should weather almost anything. Given a 5-1 scope or better that anchor is one of the highest performing anchors in the world.
Looks like you like dogs better than boats.

manyboats said:

I also have a 13lb, 18lb and 35lb Danforth, a 22lb Claw, an 18lb Manson Supreme, and a 35lb Dreadnought. Used all but the 35lb Danforth. Most up to 35 knot winds. The anchors in the pics are XYZs.

Don't know that boat Janice but she looks a bit heavy in the bow.
You should be aware that your boat with a high performance anchor like the Rocna should weather almost anything. Given a 5-1 scope or better that anchor is one of the highest performing anchors in the world.
Looks like you like dogs better than boats.

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Sorry dear Eric, but I just have to call you out on this one. You are extremely conscious of the need to avoid excess weight in the bow, as noted in your comment to Janice above, yet you have all that hardware, presumably on board, because it's a bit late to decide what anchors to take along out of the garage when you are out at sea, and decide the ones you have are not suitable, so how on earth does that work. You must be dragging so much dead weight around, even if used as ballast and not in the bow, it must be upping your fuel consumption and taking up valuable space. Why don't you just buy one decent anchor, and sell all the others except for one favourite as the spare/stern anchor - I suggest your Manson Supreme.
Why don't you give Rex a hail, and see what deal he might cut you to ship a Sarca #5 to your door..?

You've told me many times I should stop buying more anchors and you've told me many times I should buy one like yours. Hmmm?

As to weight .. add'um all up. Dosn't amount to much (about 50lbs) compared to 300' of chain. And I usually only have three anchors aboard. On my trip south I was play'in anchor tester but was so pleased w my modified XYZ I used it more than the others. I was amazed at how well it worked. Once I got down here I was planing on making a pointed "nose" for it (as in pics) but since I think it has more holding power than any anchor in the world now I think I'll keep it like it is and use another anchor when it dos'nt set.

And if I get another anchor it will probably be a Fortress.