sail-world.com
 
 
News Home Cruising Australia Cruising USA Cruising Canada Boats for Sale Sail-World Racing Photo Gallery FishingBoating
Newsletters Video Gallery
Sail-World.com : Know These Seabed Secrets for Sailing Navigation Safety!
Know These Seabed Secrets for Sailing Navigation Safety!


'Approaching St. Maarten in the Caribbean'    Captain John Jamieson

Did you know that if you can read sea bottom chart navigation symbols, this will help you when you anchor or go aground? This skill could even save you lots of money if you choose to clean and paint your bottom--without a haul out!

Sea bottom abbreviations tell you about the texture, color, and type of material. Navigation charts always show the type of material, such as sand, clay, or oyster shell, but could show texture and color from records gathered hundreds of years ago...

Sailor's Tale from Long Ago:
In the days of the square riggers, sea captains collected and shared depth and seabed information with each other.
A ship that approached an island landfall in thick, pea-soup fog could tell the distance off the reefs with the aid of an armed-lead.

The lead-line was the original depth sounder. Cylindrical in shape with a long marked line--it had a hollowed-out bottom. The boatswain would smear a coat of tallow in the hollow so that a sample of the bottom would stick to the lead. Then, he was sent as far forward as possible to 'cast the lead'.

The lead was cast and the line eased until it became slack upon contact with the bottom. The boatswain read the sounding from the marked line, pulled up the lead, turned it over, and examined the embedded sea-bottom sample.
Was it yellow sand? Or brown sand mixed with bits of shell? Or black mud?

He shouted back the sounding, texture, and type of bottom to the Captain. 'By the mark 6! With white sand and shells, Cap'n!' This sequence continued, sometimes for hours. From this, the learned captain determined his distance off the 'ship-killing' breakers ahead.

Use This Five-Factor Seabed Strategy:
Understand the nature of the seabed you sail over to make the best decision when you anchor, go aground, or careen your hull. With this knowledge, you will have the skill and confidence to...

* Choose the best bottom for anchoring.
* Select the right type of marine anchor.
* Decide how to anchor in poor bottoms.
* Locate an ideal spot for careening.
* Take the right action when grounded.

Use this seabed symbol guide to become familiar with the bottom abbreviations shown on your nautcial chart or chart plotter. -  Captain John Jamieson  
Let's take a look at each of these five factors, use the seabed table, and determine how to use this in most any small boat cruising situation. Use the illustrated table of seabed symbols and abbreviations to the right, along with the steps.

1. Choose the best bottom for anchoring :
Which three of these twelve bottom types would be your choice for the safest anchorage for a marine anchor? Sand, hard mud and clay give your sailboat anchor the best chance of a good, solid set.

Look at the second column at the bottom two abbreviations. Many charts show so or sft; h or hrd--alone, without a bottom type. Locate the closest bottom type within a mile. For example, if you see S within a mile of a hrd abbreviation, there's a good chance the bottom consists of hard sand. An M would mean hard mud.

2. Select the right type of marine anchor:
Almost any anchor will hold in protected waters in hard or sticky mud or clay. Cruisers in island anchorages often dive on sand bottoms to make sure the boat anchor buries up to the top of the shank. Lightweight boat anchors--like the Fortress or Danforth--hold well in most sand, mud, or clay bottoms.

If you have any doubt whatsoever about the quality of the sea bottom (too soft, too hard), amount of swing room, or protection from the elements, use one or more larger plow or claw anchors (the Delta, CQR, Rocna, Bruce or similar). Follow this golden rule of anchoring: 'When in Doubt, Get the Plow or Claw Out!'

3. Decide how to anchor in poor bottoms:
If you must anchor in soft bottoms (sand or mud), grasses, or any of the hard bottoms shown, take extra precautions. Use the heaviest anchor aboard with a trip line. Put out a second anchor or send down a sentinel in tight anchorages with less swing room or heavy marine weather. If necessary, rent a mooring for the night. That is, unless you have any one of the 'new generation' anchors which are sometimes almost too good in soft bottoms.

4. Locate an ideal spot for careening:
This skipper careens a small cruising sailboat with anchors inside a calm harbor. World cruisers realize the cost benefits of careening the hull for cleaning and painting where haul outs are expensive--or non-existent!

To careen, you must find a bottom that will provide a firm, but soft cushion--such as sand or grass. The tidal range should be large enough to cause the location to dry out at low tide. Position the boat to heel over so that the deck faces away from the incoming tide. This prevents flooding the decks and below decks.

Cushion the low side to protect the hull. Scrape, clean, and paint the high side. When the tide comes in, turn the boat around, and repeat the process. In calm, protected waters you might be able to stand the hull upright. The keel must be strong enough to support the weight of the sailboat hull. Use anchors or timbers to keep the boat straight and the weight distributed.

5. Take the right action when grounded:
Depending on where you sail, most of us go aground sometimes--but the initial action you take makes a big difference. You need to know the type of bottom right away. Mud, sand, and clay aren't problems for most small cruising boats in protected waters.

But any bottom can turn dangerous in choppy seas, ground swell, or areas with lots of boat wake. If you ground on a hard bottom, determine the type of bottom from the nautical chart or take a bottom sample with a lead line. Next, check for damage below the waterline. If you have a crack or hole, stay put! Repair the damage with a temporary patch before you back off that shoal to prevent flooding.

Know these simple abbreviations to increase the safety and security of your cruising boat. That way, you will be able to choose a perfect anchorage, take the best action when grounded, or even save big $$$'s on your next haul out!

John Jamieson (Captain John) with 25+ years of experience shows you the no-nonsense cruising skills you need for safer sailing worldwide. Visit his website at www.skippertips.com. Sign up for the Free, highly popular weekly 'Captain John's Sailing Tip-of-the-Week'. Discover how you can gain instant access to hundreds of sailing articles, videos, and e-Books!


by John Jamieson

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=112696

7:51 PM Thu 1 Aug 2013GMT


Click here for printer friendly version
Click here to send us feedback or comments about this story.







Sail-World Cruising News - local and the World

The record-setting North American winter of 2015 has left us with all kinds of remarkable images, most of them of snow and ice. But a photographer on Nantucket found something most of us have never seen – nearly frozen waves. ... [more]  

Coast Guard crews continue the search Monday for Richard Byhre, the 76-year-old sailor who did not return from his sailing trip as expected. ... [more]  

Rio de Janeiro's state environmental agency says it is investigating a fish die-off that has left thousands of carcasses floating in waters where sailing events are to be held when Brazil hosts next year's Olympics. ... [more]  

The Salty Dawg Rally (SDR), a cruising rally that has quickly grown to be the most popular one of its kind on the U.S. East Coast, announces the Spring 2015 rally plans, when members of the SDR once again sail out of their ‘Winter headquarters’ in the Caribbean and head home for the warmer months of the year. ... [more]  

Dutch Chief Mate suspended following tragic yacht incident by Maritime and Coastguard Agency Press
On the 8th June 2014 the 'Shoreway', a 98 metre 5000 tonne dredger, owned by Koninklijke Boskalis Westminster NV, collided with a Moody 31 sailing yacht 'Orca' at the entrance to the River Orwell in Suffolk. At the helm of the Shoreway at the time was Mr Gerardus Chapel who was employed as Chief Mate. ... [more]  

Last year, OceansWatch trialled a Climate Change adaptation program in two communities in the Solomon Islands which have been identified as one of the countries that will be most affected by the rising sea levels and increased storm conditions. The low coral atolls where we work are especially vulnerable. ... [more]  

Sailors for the Sea and Cruising Club of America will work together to encourage sailors to become stewards of the ocean. Sailors for the Sea, a leading conservation organization that engages, educates, inspires and activates the sailing and boating community toward healing the ocean, will partner with the Cruising Club of America (CCA), an international organization of over 1,300 sailors ... [more]  

Safety at Sea seminar is being held on Saturday, March 14 at SSYC. Before you head offshore to cruise or race, join us for the most authoritative daylong seminar on safe seamanship, heavy weather tactics, weather forecasting, communications and boat preparation. ... [more]  

The European Commission considers a Greek cruising tax introduced at the end of 2013 to be lawful following concerns from Britain's Royal Yachting Association (RYA). Although it has yet to be implemented, the new Circulation Tax (TPP) applicable to all boats over 7m sailing in Greek waters, has now been ruled lawful by the European Commission. This report by Yachting World. ... [more]  

Rescued Australian father and son are recovering fast by Sean Flynn | The Newport Daily News
The Australian father and son who were rescued from their 43-foot sailboat Sunday morning in 60-mph winds and 25-foot waves two days after setting out from Jamestown were recovering Monday at the Coast Guard Air Station in Forestdale, Mass., a village in Sandwich. ... [more]  

Airbnb may a popular 'peer-to-peer' lodging site on the web, but if you want to rent a boat in your local area or away, you’ve got options, too. Boatbound.com, Boatsetter.com and Cruzin.com are just a few of the new crop of online websites offering a chance to rent a boat for the day or weekend. ... [more]  

Australian father-son duo delays trip back home by By Matt Sheley | The Newport Daily News
Lousy weather and a wonky autopilot kept the 43-foot sailboat Sedona docked Monday at the Conanicut Marina in downtown Jamestown. Australians Reg and Jason McGlashan rode out the snow in the boat’s cabin, waiting for a marine electrician to show up and fix its electrical system. ... [more]  

Reg and Jason McGlashan spent the weekend getting ready to embark on the journey of a lifetime. In freezing weather, the father-and-son team prepared the 43-foot sailboat 'Sedona' for their 8,600-nautical-mile trip back home to Port Macquarie, Australia. ... [more]  

With shark encounters and bites on the rise, Lindsay Lyon, Shark Advocate and Managing Director of Shark Shield, the world’s only proven shark deterrent technology, provides his tips on preventing a shark attack as the last days of summer roll in. ... [more]  

The National Marine Manufacturers Association (NMMA) and Boating Writers International (BWI) announced today winners of the 2015 Progressive Insurance Miami International Boat Show Innovation Awards, presented during the annual Industry Breakfast at the Miami Beach Convention Center. ... [more]  

The Baja Ha-Ha… The 750-mile cruiser rally from San Diego to Cabo San Lucas beckons with adventure, fun and memories-to-be-made. This year 171 boats and 525 participants answered the call. ... [more]  

Oceans of Hope is a Sailing Sclerosis Foundation project that aims to change perceptions of Multiple Sclerosis (MS), inspiring people with the disease to overcome their own personal challenges by telling the stories of those taking part in the first ever circumnavigation by a yacht crewed by people with MS. ... [more]  

Tropical Cyclone Marcia is moving quickly through the Coral Sea towards the Queensland coast. The recent movement has been to the southwest, and it is expected to maintain this general motion through to landfall on the eastern Queensland coast between St Lawrence and Bundaberg early on Friday. Tropical Cyclone Marcia is expected to slowly intensify, with the possibility of reaching category 2 inte ... [more]  

Between 18th-25th May 2015 I will spend 7 days and nights in a life raft in Portland Marina, Portland Harbour, Dorset. This is a twofold exercise, firstly to raise money for Great Ormond Street Hospital families centre, and secondly to allow Professor Mike Tipton and his team at Plymouth University conduct experiments on me. ... [more]  

Fusion®, a worldwide leader in marine audio, announced today the release of its revolutionary high-performance marine audio systems, the Fusion 750 and 650 True-Marine™ Entertainment Series. Approaching audio engineering from the perspective of the boat enthusiast and incorporating the latest marine technologies and environmental protection ... [more]  

Boat owners cruising in Turkish waters are facing more difficulties because a new law regarding Residence Permits is confusing everyone concerned. ... [more]  

I was ruined...completely and utterly ruined. At the young age of 22, my very first trip to the Caribbean was to Eleuthera, which is, in my opinion, the most beautiful place on earth. It will now be an uphill battle for me to surpass my visit there. ... [more]  

RYA Suzuki Dinghy Show 2015 - Over the weekend of 28 February-01 March everything you ever wanted to know about dinghy sailing plus hundreds of boats, brands and kit can be all be found under one roof at Alexandra Palace, North London. ... [more]  

Don Macpherson developed a passion for sailing in his twenties while cruising with his father, a navigator in the US Navy, on the family Swan 57. ... [more]  

OCA Series - Face the fear with Julie Salisbury as she takes you on a journey at sea, encountering sharks and jellyfish, complete darkness alone 1,000 miles from land, battling malaria, a debilitating back injury, and being jilted in Malaysia and left alone with no money, friends, or home. ... [more]  

Dominica has been on 'the' list for quite some time now and when I actually get to do something on 'the' list, my heart skips a beat! Although Dominica still remains somewhat off-the-beaten track for boaters, it is located right in the middle of the chain of Caribbean islands and can be easily accessed from Antigua and Guadeloupe to the north or Martinique and St. Lucia to the south. ... [more]  

Yachts arriving in the Galapagos are now subject to more stringent checks to prevent introduced species invading the Islands. ... [more]  

Cruising under Power - With more and more members trading in the sails for the power option we thought we’d take a look and see if taking on the Power option really was turning to the Dark Side! ... [more]  

Boat Owners Association of The United States (BoatUS) Chairman and Founder Richard Schwartz, who created and grew the association to become the predominant advocacy and boater services organization for the nation’s recreational boat owners, passed away Wednesday after a short illness. He was 85. ... [more]  

50th Newport Bermuda Race - When I wrote my history of the race, A Berth to Bermuda, in 2006, one theme wove its way through the narrative: Anyone who wishes to win the oldest of all ocean races must be prepared to be bold in choosing strategy and tactics. Jim McCurdy designed Carinas and sailed with the Nyes, as did his daughters, Hope and Sheila. ... [more]  

About five percent of our land-based mess (12.7 million metric tons of plastic) estimated to wind up in the water. Since their invention roughly 75 years ago, plastics have become increasingly prevalent in the consumer marketplace. Today, we use and dispose of plastics on a daily basis, in products like bottled water and grocery bags. Plastics now represent a significant portion of the solid waste ... [more]  

At 20.29 UTC, Captian Piotr Kuzniar, & his 10 man polish crew onboard the 67 foot yacht Selma, reached the edge of the ice in the Ross Sea, at 78,43.S in the Bay of Whales, just over 100 nautical miles farther south then the previous record. ... [more]  

ARC USA Rally - Offshore Passage Opportunities (OPO), the largest crew networking service in North America, has reserved 24 crew berths for amateur crew aboard five boats it is 'delivering north' during the upcoming ARC USA Rally. A Swan 57, Swan 53, two Swan 46s and a Beneteau 50, each with a professional skipper and five crew, will start the ARC USA Rally on May 9 ... [more]  

Setouchi International Yacht Rally preview
Cruising yacht disappears in Bay of Islands
Getting your gear (wheel) on
Caribbean Safety and Security Net 2014 year end report
Boat Docking Secrets - How to Avoid Springline Snap-back
New legislation would fix renewable fuel standard
New legislation would fix renewable fuel standard
Provisioning the aCappella Way
Ilen’s Whiskey Plank Ceremony at Hegarty’s Boatyard
Best Loch Ness Monster evidence may have been destroyed
Tall ship falls over - Could your boat do this?
Two Somali pirates appeal in deaths of four Americans aboard yacht
Producing jet fuel from ocean algae
FUSION® unveils 750 and 650 Series Marine Entertainment Systems
The true story of Donald Crowhurst set for a major film adaptation
Humans drive 500 species of land animals extinct, now marine?
Predicting coral reef futures under climate change
Sailors for the Sea launches ocean conservation movement to heal ocean
Family rescued after catamaran breaks in half
2015 Ocean Cruising Adventures - First to finish without really trying
Winter Storm Juno expected to impact Northeast - Take precautions!   
Sailing Sclerosis Oceans of Hope arrives in Panama City + Video   
Ocean Cruising Adventures Series preview   
Planning an open ocean cruise? Become a Citizen Oceanographer   
Croatia First Regatta - Brand new limited entry one design event   
Boot 2015 – Worlds largest boat show shows optimism   
Doyle Sails offer sail repair and basic rigging service at BOISW   
World Arc Leg 2 - Fleet depart for San Blas   
World Arc - First arrivals to St Helena island   
2014 warmest year since records began + Video   
Volcano creates large new Tongan island   
Summer camps for teens aboard an extraordinary tall ship   
Highland Yacht Club - Lake Ontario’s hidden jewel of a Yacht Club   
Particular Harbour – Gananoque   
SE Asia tanker hijacks rose in 2014 - IMB report reveals   
Rescuing Ben Ainslie from a boat? Stranger things have happened at sea   
Christmas Caribbean Rally - Success, new dates, multihulls offer   
Cruising like a Vendée Racer   
World ARC - Two rally fleets set sail   
Hidden battles on Reefs - How will corals fare in a changing ocean?   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph, contact the photographer directly.
XLXL VIR CRU NH
LocalAds   DE  ES  FR  IT