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SEAMANSHIP CH. 9 ANCHORING

SEAMANSHIP CH. 9 ANCHORING. The study references for this chapter are again found in Chapman’s Piloting, Seamanship and Small Boat Handling, along with this Power Point Presentation and the USCG Auxiliary Student study guide and practice questions. QUESTIONS TO CONSIDER.

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SEAMANSHIP CH. 9 ANCHORING

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  1. SEAMANSHIP CH. 9 ANCHORING The study references for this chapter are again found in Chapman’s Piloting, Seamanship and Small Boat Handling, along with this Power Point Presentation and the USCG Auxiliary Student study guide and practice questions.

  2. QUESTIONS TO CONSIDER • The process of anchoring is mostly a combination of “a SEAMAN’S EYE and common sense”. • What do you want the anchor to do? • How big an anchor do you need? • Where will you be anchoring? • Where will you keep it on the boat? • Who will handle the anchor

  3. WHAT DO YOU WANT THE ANCHOR TO DO? • You want the anchor to HOLD THE BOAT WHERE YOU PUT IT. • That implies that the anchor must STAY where you PUT it. • It must be light enough to comfortably handle and yet heavy enough to dig in and hold the bottom. • It must be designed for the bottom types you will encounter the most. • It must hold in all kinds of weather, seas and current.

  4. HOW BIG AN ANCHOR DO YOU NEED? • A mistaken concept is that the effectiveness of anchor depends upon the weight, for it’s holding power. For most Auxiliaryvessels ( 16-26 ft.) a utility – type 12-18 lb. type is satisfactory. Deeper draft vessels may need a little more. • The anchor’s holding power depends on the design. • There are anchors designed for every type of bottom known. Try to choose the anchor for your vessel’s weight, handling characteristics, use and area of operation bottom type. • They are made from aluminum, steel, cast iron and bronze, depending on the desired use.

  5. DESIGN • The primary motivation for the design of an anchor, is it’s HOLDING POWER. • Most of the characteristics of the anchor reflect it’s ability to “DIG IN” and continue to hold, without turning over, flipping, or simply breaking loose. • Additional considerations are its ability NOT to foul on anything it may encounter. • Finally, the ease of maintenance feature must be considered.

  6. WHERE WILL YOU BE ANCHORING • Bottom type is probably the greatest item of consideration for the TYPE of anchor you will need. Consult your navigation chart in your operating area. It’s printed right on it. • Lightweight anchors such as the Danforth-type by Danforth or Fortress, the Plow, the Delta, the Bruce, the Max, the Kedge, the Navy-type and the Grapnels, Folding – types, and the Northill and Mushroom – type are either general – purpose or designed for a limited range of specific uses.

  7. STORING THE ANCHOR • It and all other accompanying gear such as the rode, should be stored in a location “FOR IMMEDIATE USE” mode. • It should remain free of all entanglements or any fouling apparatus. • There should be ample room for the rode to run free.

  8. WHO WILL HANDLE THE ANCHOR? • Do not buy an anchor that cannot be comfortably handled by your crew. It will not be a satisfying experience. • Consideration should be given to the physical capabilities of the crew including their eyesight, hearing capabilities, their limitations, training and knowledge of the functions and importance of ANCHORING.

  9. ANCHOR TYPES

  10. MORE ANCHOR TYPES& NOMENCLATURE Flukes

  11. SAMPLE ANCHOR TYPES http://www.go2marine.com/category.do?no=12417&view=item

  12. THE KEDGE, NAVY AND GRAPNELS KEDGE – types: The Hereshoff, Fisherman and the Yachtsman. All Excellent on heavy grass or weed bottoms. Also commonly used to “kedge” a grounded boat off the bar. NAVY – types: Not the best for small boats. They must weigh far too much before their holding power becomes efficient. Used on big ships because they are flukeless so as to be retrieved into hawse pipes. GRAPNELS: Not recommended for small boats. Good in rocks. Must use a tripping line to free them otherwise, you are permanently attached to the bottom!

  13. TWISTED THREE STRAND NYLON • All of the gear, collectively, between the anchor and the boat, is called the “ANCHOR RODE”, whether it is of chain, synthetic fiber or a combination of both. • The most widely used material for the anchor line is three-strand twisted or double braided nylon. Chain makes a good rode but the weight is generally prohibitive. • DOUBLE-BRAIDED NYLON is elastic. The stretch qualities (15%-25%) make it ideal for stress loads in heavy seas while at anchor. Stow it out of the direct sunlight!

  14. BRAIDED SYNTHETIC LINE DOUBLE BRAIDED NYLON: Gives exceptional stability without the twisting characteristic of the twisted variety. No kinks. Can be easily faired through fittings and into storage. You need to “fake” it down to prevent a “set”.

  15. CHAIN • CHAIN is for vessels which would require too large a diameter of nylon for an efficient anchor line. It can be used, however, as a personal choice. • In heavy coral or rock areas, chain is ideal and in some cases, indispensable to reduce or eliminate excessively heavy chafing. • BBB, PROOF COIL and HIGH TEST CHAIN( the best ): The three kinds of chain most commonly used as anchor chain. • CHAIN must be matched to the “wildcat” used to hoist and lower it. • IDEAL COMBINATION: Nylon ,with 6-8 ft. or longer length of chain. Chain helps to keep angle of stock very low to bottom for max dig power of flukes.

  16. ANCHORLINE HARDWAREEYESPLICE – THIMBLE - SHACKLE

  17. CLEATS, SAMPSON POSTS, BITTS, CHOCKS, ETC. ALL FITTINGS: Should be through-bolted and backed up withsteel plates, to reduce the possibility of a strain on the anchor line which has been secured to this hardware, pulling the bolts back through the deck or anchoring surface. REMEMBER: It is the objective of the anchoring maneuver, to keep the boat’s position stationary. If the fittings pull out and the anchor runs free or drags as a result, the failure of the fitting may jeopardize the vessel’s safety.

  18. SCOPE • DEFINITION: The length of the anchor rode in relation to the height of the bow above the bottom of the water body ( R÷ Bh ) where R = Rode length and Bh = Bow Height of the bow above the water. • Interpretation and application: The length of the rode. • You know you should have a minimum scope of 5 : 1 but should have 7 : 1 in fair weather. You have 80 ft. of rode out in 10 ft. of water which gives you a scope of 8:1 (80 ÷ 10). • However, if your bow is 3 ft. above the water your actual scope is only (80 ÷ 13 = approximately a little more than 6! • *** The SCOPE is a MAJOR FACTOR that determines whether you willDRAG or HOLD!!***

  19. ANCHORING – FAVORABLE CONDITIONS

  20. PERMANENT MOORING

  21. SELECTING THE ANCHORAGE 1. ALWAYS USE YOUR CHART to pick your anchorage. It’s your “road map” to the area, in detail. 2. Try to pick a bottom that has little or no mud, loose sand or heavy grass, for better holding characteristics for the anchor. 3. Try to anchor with your bow into wind. This will help to keep your sleeping area free of insects living on the surrounding land mass. It also will help in getting underway as you are alreadyheading out and you do not have to turn around! 4. Try to pick an orientation which will give you as much lee as possible, in case of inclement weather.

  22. APPROACHING THE ANCHORAGE • Keep in mind, if you use only one anchor, you are free to rotate 360 degrees on your anchor during the night or day, possibly over dangerous rocks below or into other anchored boats in the anchorage. Keep this in mind in choosing the spot and when approaching. • Use your GPS or suitable range marks you have chosen, to navigate to the desired spot to drop the anchor. • Visualize other vessels already anchored and how they might swing or set up in any current or wind, before your final selection of a good spot.

  23. LETTING GO THE ANCHOR • THINGS TO CONSIDER • BOAT’S MOTION • LOWERING THE ANCHOR • SETTING THE ANCHOR • DRAGGING ANCHOR • DECK FASTENERS

  24. LETTING GO THE ANCHOR • As a good sailor, your anchor and all the necessary gear is “ready”.That means it is properly and adequately attached with secure fittings, backed, and the deck is cleared for working. • STOP ALL HEADWAY. Reverse you engine at idle speed. Just as you begin noticeable sternway, lower the anchor slowly but positively until it hits the bottom on the crown. • The goal is to PREVENT fouling.

  25. SETTING THE ANCHOR • An anchor MUST be SET to yield it’s FULL HOLDING POWER. • This is somewhat “trial and error” because every boat is different. • Pay out the rode until you get to your pre-selected marker. Take a turn or two around a cleat. Check things out to see if it is holding. • Keep doing this until you are satisfied it is holding. • When you are satisfied, stop the rode with whatever system you have. • Pick out at least two ranges, one on each side at about 45 degree angles to each other and make a note. Your “anchor watch” can detect drift by these sightings later and take corrective action..

  26. WHEN THE ANCHOR DRAGS • Check the bearings of the two ranges you chose when you came into the anchorage. • Be prepared to get underway immediately and to fend off, if necessary. • If there is no immediate danger of collision and you have enough room, let out additional scope and test for holding each time. • On the engine, bring the bow back into the wind to ease the strain on the rode. • If it is reasonable, raise the anchor to clear any fouling that might have taken place.

  27. INCREASING THE HOLDING POWER

  28. GETTING UNDERWAY • ALWAYS have your mainsail up and set or your engine on and in gear, for positive control, before breaking the loose from the bottom. • Setting in a current, near shore, grass and other like debris will entangle in the anchor rode. • Whipping the line up and down in a snapping motion will help clear most all of it. • Do not store the anchor line with any of this debris as it will hasten it’s breakdown and carries this moisture down below decks where it is most undesirable. • KEEP THE ANCHOR OFF OF THE HULL!

  29. USING TWO ANCHORS • Use of two anchors, a “working” anchor and a “storm” anchor, will help to correct for deficiencies with only one anchor, when in heavy weather. The STORM anchor can be run out and set without moving the working anchor at all. • Deep draft sailboats will lie head into the wind naturally. Power boats and small skiffs tend to put their sterns into the wind, if left alone. It may become necessary to use two anchors with these vessels to keep them out of trouble. • http://www.uspowerboating.com/anchoring_gifs/two_anchors.gif

  30. ANCHORING AT NIGHT • Don’t forget your “ANCHOR LIGHT” to meet your boat’s requirements of the Rules. • In addition, during the day, if you are required to meet the rule, your SINGLE BLACK BALL dayshape should be flying from your crow’s nest.

  31. REVIEW QUESTIONS NO. 1 • The most widely used material for the anchor line is_________ • a. polypropylene • b. polystyrene • c. nylon • d. rayon

  32. REVIEW QUESTIONS NO. 2 2. All gear, taken collectively, that lies between the boat and it’s anchor is called the _________. a. line b. mooring c. rode d. cast

  33. REVIEW QUESTIONS N O. 3 3. The lightweight type anchor is excellent on ______ and sand bottoms. a. rock b.hard c. gravel d. mud

  34. REVIEW QUESTIONS NO. 4 4. Chain is designated by the __________ of the material in the links. a. length b. weight c. metal d. diameter

  35. REVIEW QUESTIONS NO. 5 5. The ideal rode for most average conditions is a combination of _________ and a short length, less than 1 fathom of chain. a. cable b. nylon c. rayon d. polypropylene

  36. REVIEW QUESTIONS NO. 6 6. When anchoring under favorable weather and sea conditions and using nylon line, a scope of ________ might be considered a minimum. a. 5 : 3 b. 4 : 8 c. 5 : 1 d. 5 : 1

  37. REVIEW QUESTIONS NO. 7 7. When anchoring, the anchor should _____ be lowered when the boat has any way on. a. always b. never c. probably d. must

  38. REVIEW QUESTIONS NO. 8 8. If an anchor drags, the first step in trying to get it to hold is to_______. a. pay out more scope b. take in scope c. change anchor size d. try another spot

  39. REVIEW QUESTIONS NO. 9 9. When chocks, cleats and other fittings are used on deck, they must be _________ and reinforced with a strong backing plate. a. heavily screwed b. through-bolted c. screwed d. stopped

  40. REVIEW QUESTIONS NO. 10 10. The type of anchor traditionally used for permanent moorings is the _______. a. pan b. mushroom c. folding d. navy

  41. END CHAPTER 9

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